WO2012152866A1

WO2012152866A1 - Stalk roll for use in stalked crop harvesting header

Info

Publication number: WO2012152866A1
Application number: PCT/EP2012/058638
Authority: WO
Inventors: Stanislaw KUDLA; Dariusz ADAMCZYK
Original assignee: Cnh Belgium N.V.
Priority date: 2011-05-10
Filing date: 2012-05-10
Publication date: 2012-11-15
Also published as: BE1019972A3; EP2706835A1

Abstract

The present invention relates to stalked crop harvesting machinery, and in particular, to a stalk roll for use in a stalked crop harvesting header, which is both light weight and easy to manufacture. The light weight stalk roll according to embodiments of the present invention comprises a straight shaft (10), and at least one blade (30) mounted on the shaft by means of a fastening means (30) screwed into a mounting place (40) formed in a wall of the shaft (10) by means of flow drilling.

Description

Stalk roll for use in stalked crop harvesting header.

Field of the invention

The present invention generally relates to stalked crop (for example maize) harvesting machinery, and more particularly to a stalk roll shaft for use in a stalked crop harvesting header.

Background of the invention

A stalked crop harvesting machine as described for example in US6237314 and US4244162 comprises a header displaceable along the ground which comprises a plurality of grooves each adapted for receiving, during operation of the harvester, a row of crop stalks. An example stalked crop harvesting machine 1 is illustrated in FIG. 1. A plurality of row units 2 is positioned in front of the harvester, with each unit 2 engaging a row of stalked crop such as corn stalks as the harvester moves forward. Each unit 2 has a pair or set of counter-rotating and cooperating stalk rolls 3 with outwardly extending blades that grip the stalks and pull them downwardly and knife blades thereon cut them. Example stalk rolls are illustrated in WO 2001/08465.

In known harvesting headers, shafts for stalk rolls are made of full steel bars (FIG. 2) with blades mounted thereon (separately – as illustrated in FIG. 3 - or after first welding those blades together as shown in US3633348 – reproduced as FIG. 4). The use of such full steel bars, however, has as disadvantage: its substantial weight. In particular when taking into account that such header does comprise a large number of such stalk roll shafts, one obtains a heavy header, which as consequence requires a stronger driving motor (and hence more energy consumption). The harvesting machine to which the header is attached will also require a stronger support structure for the header. Furthermore, problems might arise with respect to stability of the combine with such a header when used in the field.

In other known harvesting headers, as described for example in FR2784263, also aiming at a light weight approach, such roll shaft is made just by welding plates together, on which the blades are mounted. This is illustrated in FIG. 5. However, such approach is less easy to manufacture, due to the necessary tolerances that must be provided due to the welding process. Furthermore, it requires the use of mounting means for the blades which comprise nuts that are difficult to access as they are located within the shaft. Mounting and/or replacing a blade in this way becomes a cumbersome task.

Summary of the Invention

It is an object of embodiments of the present invention to provide a stalk roll for use in stalked crop harvesting headers which is both light weight and easy to manufacture and allows for straight forward mounting and replacing of a blade.

The above objective is accomplished by a device and a method according to embodiments of the present invention.

In a first aspect of the invention, a light weight stalk roll for use in stalked crop harvesting header is provided, this light weight stalk roll comprising a straight hollow shaft; and at least one blade, mounted on the shaft by a fastening means screwed into a mounting place formed by flow drilling into a wall of the shaft. It is an advantage of embodiments of the present invention that they allow for a light weight stalk roll. It is an advantage of a stalk roll according to embodiments of the present invention that, in view of it being light weight, it allows for less dimensioned driving motor (and hence less energy consumption). It is an advantage of a stalk roll according to embodiments of the present invention that it allows for the use of weaker axles of the harvesting machine, to which the header is attached. Furthermore, a light weight stalk roll in accordance with embodiments of the present invention improves stability of a combine with such header during harvesting. It is a further advantage of a stalk roll according to embodiments of the present invention that it is easy to manufacture.

The blade is mounted on the shaft by screwing it into a mounting place, being a hole in the shaft wall provided by means of flow drilling. It is an advantage of embodiments of the invention that this approach allows for easy, fast, high quality and cost effective manufacturing even for small diameters of the shaft as no bolt nut is further required.

In an embodiment of the invention the shaft is made by means of extrusion, which results in a thin walled light shaft.

In an embodiment of the invention the shaft has an n-sided polygonal cross-section and n blades, each one mounted on one of the corresponding side parts of the shaft.

In a particular embodiment of the invention the shaft has a regular 4-sided polygonal cross section (and consequently 4 blades).

In a further embodiment of the present invention, each of the blades is directly mounted on the shaft. The blades do not need to be connected to one another. The lack of a welding step of the blades results in easier manufacturability as tolerances required when using a welding process can be omitted. Furthermore, if the blades are not welded to one another, one or more, but optionally not all the blades, could be replaced, for example in case of wear or break-down.

In an embodiment of the invention, each of the blades is fixed during mounting close to the mid portion and the end portions of the shaft.

In one embodiment of the invention, the position of the mounting places of each of the blades on the shaft are selected to avoid that the portions of their corresponding fastening means extending through the wall of the shaft contact each other. In case of use of identical blades (which has the advantage that one avoids the need to make a variety of blades), the blades may have more mounting (bore) holes than required for mounting the blade on the shaft.

In a second aspect of the invention, a light weight stalked crop harvesting header, suited for being attached to a stalked crop harvester, is provided. The header comprises at least one support element with at least one stalk roll rotatably connected to the support element. The at least one stalk roll comprises a straight shaft, and to the shaft at least one blade is mounted by means of a fastening means screwed into a mounting place formed in a wall of the shaft by means of flow drilling.

In a third aspect, the present invention provides a method for manufacturing a stalk roll. The method comprises providing a straight shaft, and mounting at least one blade to the shaft by a fastening means screwed into a mounting place formed in a wall of the shaft by means of flow drilling.

Particular and preferred aspects of the invention are set out in the accompanying independent and dependent claims. Features from the dependent claims may be combined with features of the independent claims and with features of other dependent claims as appropriate and not merely as explicitly set out in the claims.

Brief Description of the Drawings

The invention will now be described further, by way of example, with reference to the accompanying drawings, in which:
FIG. 1 is a schematic representation of harvesting machinery having a harvesting header with a plurality of stalk rolls.
FIG. 2 is a 3D view of a prior art shaft, which is used as basis for a stalk roll in known harvesting headers, the shaft made of a full steel bar.
FIG. 3 is a cross-sectional view of a system where a full steel bar stalk roll as in FIG. 2 is mounted, provided with blades bolted onto the stalk roll.
FIG. 4 is a cross-sectional view of a prior art stalk roll, made by welding blades together, and the entire welding set is then mounted on a shaft, made of a full steel bar.
FIG. 5 is a cross-sectional view of a prior art stalk roll, made by just welding blades together, hence omitting a supporting shaft.
FIG. 6 is a 3D view of a stalk roll shaft according to an embodiment of the present invention, in particular a straight shaft which is hollow and comprises mounting holes.
FIG. 7 is a 3D view of a stalk roll according to an embodiment of the present invention, comprising a hollow stalk roll shaft with blades mounted thereon with fastening means through holes in the blades.
FIG. 8 and FIG. 9 are a side view and cross-sectional view of a stalk roll according to embodiments of the present invention, comprising a straight shaft, blades, and fastening means extending through flow drilled mounting places in a wall of the shaft for connecting the blades to the shaft.

The drawings are only schematic and are non-limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not necessarily correspond to actual reductions to practice of the invention.
Any reference signs in the claims shall not be construed as limiting the scope.
In the different drawings, the same reference signs refer to the same or analogous elements.

Detailed description of illustrative embodiments

The present invention will be described with respect to particular embodiments and with reference to certain drawings but the invention is not limited thereto but only by the claims.

It is to be noticed that the term “comprising”, used in the claims, should not be interpreted as being restricted to the means listed thereafter; it does not exclude other elements or steps. It is thus to be interpreted as specifying the presence of the stated features, integers, steps or components as referred to, but does not preclude the presence or addition of one or more other features, integers, steps or components, or groups thereof. Thus, the scope of the expression “a device comprising means A and B” should not be limited to devices consisting only of components A and B. It means that with respect to the present invention, the only relevant components of the device are A and B.

Reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, appearances of the phrases “in one embodiment” or “in an embodiment” in various places throughout this specification are not necessarily all referring to the same embodiment, but may. Furthermore, the particular features, structures or characteristics may be combined in any suitable manner, as would be apparent to one of ordinary skill in the art from this disclosure, in one or more embodiments.

Similarly it should be appreciated that in the description of exemplary embodiments of the invention, various features of the invention are sometimes grouped together in a single embodiment, figure, or description thereof for the purpose of streamlining the disclosure and aiding in the understanding of one or more of the various inventive aspects. This method of disclosure, however, is not to be interpreted as reflecting an intention that the claimed invention requires more features than are expressly recited in each claim. Rather, as the following claims reflect, inventive aspects lie in less than all features of a single foregoing disclosed embodiment. Thus, the claims following the detailed description are hereby expressly incorporated into this detailed description, with each claim standing on its own as a separate embodiment of this invention.

Furthermore, while some embodiments described herein include some but not other features included in other embodiments, combinations of features of different embodiments are meant to be within the scope of the invention, and form different embodiments, as would be understood by those in the art. For example, in the following claims, any of the claimed embodiments can be used in any combination.

It should be noted that the use of particular terminology when describing certain features or aspects of the invention should not be taken to imply that the terminology is being re-defined herein to be restricted to include any specific characteristics of the features or aspects of the invention with which that terminology is associated.

The present invention generally relates to stalked crop (for example maize) harvesting machinery, and more particularly, to a stalk roll shaft and a stalk roll for use in a stalked crop harvesting header. The stalk roll shaft, and hence also the stalk roll formed there from, is both light weight and easy to manufacture.

FIG. 6 is a 3D view of a stalk roll shaft according to an embodiment of the present invention. It shows a straight shaft 10, which is hollow, and comprises mounting holes 40 for mounting blades so as to form a stalk roll.

FIG. 7 is a 3D view of a stalk roll according to an embodiment of the present invention. It shows a stalk roll shaft 10 in accordance with embodiments of the present invention, to which blades 20 are mounted with fastening means 30, through holes 50 in the blades 20.

FIG. 8 is a view on an embodiment of the invention, in particular a cross-section of the straight shaft 10, blades 20, fastening means 30 and holes 50 in the blades 20.

As shown in FIG. 6 in combination with FIG. 7, the light weight stalk roll for use in a stalked crop harvesting header comprises a straight shaft 10, and at least one blade 20 mounted on the shaft. The shaft is hollow. The at least one blade 20 can be mounted on the shaft 10 with any suitable fastening means 30 (for example a bolt). In particular embodiments of the present invention, the fastening means 30 extends through only one wall of the shaft 10.

Illustrative for the advantage of using a stalk roll shaft according to embodiments of the present invention is the comparison of the weight of a prior art square steel bar, which is about 16.4 kg, while a stalk roll shaft according to an embodiment of the invention weighs about 13.1 kg. This provides a weight reduction on a row unit in the header of about 6.6 kg (=2 x (16.4-13.1)), and on a complete header (with, as an example only, 12 units) about 79.2 kg (=12 x 6.6).

In embodiments of the present invention, the at least one blade 20 is mounted on the shaft 10 by means of a fastening means 30 fixed into a mounting place in the form of a hole in a wall of the shaft generated by flow drilling. This type of friction drilling is a method of making holes in metal, in which the material is melted by adding high pressure and friction energy. A flow drill tool (not illustrated) comes into contact with the material of the wall of the shaft 10 using relatively high axial pressure and rotational speed. The combined rotational and downward force of the flow drill tool creates frictional heat. The generated heat transforms the material of the shaft 10 into a “super-plastic” state, thus making the material soft and malleable enough to be perforated and formed. As the flow drill tool pushes into the material of the wall of the shaft, some of the material is displaced. Some of the displaced material forms a collar around the upper surface of the workpiece, being the outer surface of the shaft 10. The rest forms a bushing in the lower surface of the workpiece, being the inner surface of the shaft 10. The resulting collar and bushing can be up to three to four times the original material thickness. The diameter of the bush is accurately determined by a cylindrical part of the flow drill tool. All this happens in a matter of seconds. Such method of generating holes by means of flow drilling is particularly suited in manufacturing engineering where one needs to join sheet metal, tubing or thin walled profiles in a simple, efficient and cost-effective way while avoiding material removal, more production steps, and/or adding external elements, which may all lead to supplementary costs and/or quality loss. This thermal drilling method produces a bushing formed from the parent material itself, which may be advantageously used for threaded applications. This bushing increases the area available for tapping. The number and strength of threads is significantly increased, compared to the number and strength of threads which would be made in the wall of the shaft 10 only. So instead of cutting the wall, the material itself is used to form a stronger connection. This system results in a very fast process, stronger joints, is cost effective while no special machines are needed, so that the required investment is small and results in high quality, while no additional components or extra production steps are required.

Once the flow drill holes and bushings are made in the shaft 10, they can be used for attaching the blades by means of any suitable threaded fastening means 30, e.g. by means of bolts. No further nuts are to be provided at the inner side of the shaft 10 in order to allow the fastening means 30 to form a reliable connection (which would not be possible if the fastening means 30 would only have a threaded connection over the wall thickness of the shaft 10). Also replacement of blades, for example in case of wear, may easily be performed by unscrewing the fastening means 30, removing the blade to be replaced, providing a new blade and attaching it onto the shaft by introducing a threaded fastening means 30 into the hole which has been formed by flow drilling before.

The shaft 10 can for example be made by means of extrusion. Extrusion is a process used to create objects of a fixed cross-sectional profile. A material is pushed or drawn through a die of the desired cross-section. The two main advantages of this process over other manufacturing processes are its ability to work materials, e.g. metal, that are brittle, because the material only encounters compressive and shear stresses.

As shown in FIG. 8 and FIG. 9, the shaft 10 has an n-sided (here demonstrated with 4) polygonal cross-section and n (4 in the example illustrated) blades 20, each one mounted on one of the corresponding side parts of the shaft 10. A polygon is traditionally a plane figure that is bounded by a closed path composed of a finite sequence of straight segments. These segments are called its edges or sides. A regular polygon is a polygon which is equiangular (all angles are equal in measure) and equilateral (all sides have the same length). It is to be noted that according to embodiments of the present invention, each of the blades 20 are only mounted on the shaft 10 and not connected to each other. Also the holes 50 in the blades 20 and the fastening means 30 (bolts) are shown here.

The blades are mounted at suitable locations, e.g. close to the mid portion 70 and the end portions 80, 90 of the shaft 10, the mid portion 70 and end portions 80, 90 being defined in terms of the longitudinal direction L of the shaft 10, as illustrated in FIG. 7.

In one embodiment of the invention, the position of the mounting places 40 (e.g. threaded bore holes in accordance with embodiments of the present invention made by the flow drilling process) of each of the blades 20 on the shaft 10 may be selected so as to avoid that the portions of their corresponding fastening means 30 extending though the wall of the shaft 10 contact each other. In case of use of identical blades 20, the blades 20 will have more mounting (bore) holes 50 than required for mounting the blade 20 on the shaft. This is illustrated in FIG. 7, FIG. 8 and FIG. 9.

As shown in the side view in FIG. 8 and in cross sectional view in FIG. 9, the shaft may have a regular 4-sided polygonal cross section (and consequently 4 blades).

The invention also provides a light weight stalked crop harvesting header, suited for being attached to a stalked crop harvester. Such header according to embodiments of the present invention comprises at least one support element with one or more stalk roll shafts rotatably connected to the support element, each of the stalk rolls comprising a straight, hollow shaft 10, and at least one blade 20 mounted to the shaft 10.

In another aspect, the present invention provides a method for manufacturing a stalk roll. The method comprises providing a straight, hollow shaft, and mounting at least one blade to the shaft.

In particular embodiments of the present invention, providing a shaft may comprise providing a shaft by means of extrusion. This may provide a light weight shaft, e.g. of small diameter.

In particular embodiments of the present invention, mounting at least one blade 20 to the shaft comprises connecting the blade to the shaft by means of a fastening means 30 screwed into a hole 40 in a wall of the shaft 10 formed by flow drilling. Flow drilling is particularly useful in case of shafts provided by means of extrusion. In case of flow drilling, no nuts need to be provided at the inside of the hollow shaft for receiving a fastening means such as for example a bolt. Furthermore, when using flow drilling, it is not disadvantageous that the walls of the extruded shaft only have a limited thickness. This limited wall thickness does not allow for the arrangement of a hole with sufficient depth for arranging a threaded section for cooperating with the fastening means 30. Flow drilling has the advantage that part of the material of the shaft 10 will be used for reinforcing the threaded connection, as if the wall were thicker than it actually is.

Claims

A stalk roll for use in stalked crop harvesting header, comprising a straight shaft (10) and at least one blade (20), mounted on the shaft (10), wherein the shaft (10) is a hollow shaft, and the at least one blade (20) is mounted on the hollow shaft (10) by means of a fastening means (30) screwed into a mounting place (40) formed in a wall of the shaft (10) by means of flow drilling.
The stalk roll according to any of the preceding claims, wherein the shaft (10) is made by means of extrusion.
The stalk roll according to any of the preceding claims, wherein the shaft (10) has a n-sided polygonal cross-section, each side of the cross-section defining a side part of the shaft (10), and n blades (20) are each mounted on one of the corresponding side parts of the shaft (10).
The stalk roll according to claim 3, wherein the shaft has a regular 4-sided polygonal cross section.
The stalk roll according to any of claims 3 or 4, wherein each of the blades (20) are directly mounted on the shaft (10) and are not connected to each other.
The stalk roll according to any of claims 3 or 4, wherein each of the blades (20) are directly mounted on the shaft (10) and are not connected to each other.
The stalk roll according to any of the previous claims, wherein the positions of mounting places (40) of each of the blades (20) on the shaft (10) are selected so as to avoid that the portions of their corresponding fastening means (30) extending through the wall of the shaft contact each other.
The stalk roll according to claim 7, wherein the blades (20) are identical and have more mounting holes (50) than required for mounting the blade on the shaft (10).
The stalk roll according to any of claims 1 to 6, wherein the position of the mounting places (40) of each of the blades (20) on the shaft (10) are identical for all blades.
The stalk roll according to claim 9, wherein the blades (20) are identical and have just enough mounting holes (50) as required for mounting the blade on the shaft (10).
A light weight stalked crop harvesting header for being attached to a stalked crop harvester, comprising at least one support element with one or more stalk rolls according to any of the preceding claims, being rotatably connected to the support element.
A method for manufacturing a stalk roll, comprising providing a straight hollow shaft, and mounting at least one blade to the hollow shaft by a fastening means (30) screwed into a mounting place (40) provided into a wall of the shaft (10) by means of flow drilling.