Lowerable roller set of a secondary cutting unit for a combine harvester

A header for a combine harvester has a primary implement and a secondary implement with a roller unit. The roller unit has a frame element, an outer roller set with a rotatably supported roller and a central roller set with a rotatably supported roller. The central roller set is guided on the frame element to be lowerable relatively to the external roller set.

This application is the US National Stage filing of International Application Serial No. PCT/EP2014/064657 filed on Jul. 8, 2014 which claims priority to German Application 10.2013.107.148.1 filed Jul. 8, 2013, each of which is incorporated herein by reference in its entirety.

TECHNICAL FIELD OF THE INVENTION

The invention relates to a header for a combine harvester with a primary implement and a secondary implement.

A combine harvester has a front harvesting device—the so-called “header”—comprising a main cutting unit. The main cutting unit is the primary implement of the combine harvester with which the crop, e.g. wheat, is cut. Typically, the secondary implement is mounted at the rear of the “header” and serves to fulfil an additional function.

In particular, the combine harvester can be configured so that its main cutting unit for the crop is set at a relatively large horizontal distance from the ground (“high cut”). in this way, the mass of the stems fed into the combine harvester is reduced. The secondary implement, configured as a cutting implement, serves the purpose of cutting off the remaining, comparatively long stubbles from the ground and to cut them up.

The secondary implement can fulfil various functions. In particular, it can encompass cutting-off, cutting-up, comminuting or chopping. Other possible operations are ground processing, opening up of the ground, collection of vegetal components, sowing, etc. For instance, the secondary implement can also be a mower, a cutting unit, or a swathing arrangement.

STATE OF THE ART

A header for a combine harvester is known from international patent application WO 2013/011138 A. The header has a primary implement, which is configured as the main cutting unit of the combine harvester. The header further has a secondary implement, which is configured as a cutting unit. The secondary implement comprises a roller unit with a frame element and outer roller sets with a rotatably supported roller. Further, a central roller set with a rotatably supported roller is fixed to the frame element.

Another header for a combine harvester is known from German patent application DE 10 2011 051 981 A.

OBJECT OF THE INVENTION

The present invention seeks to solve the problem of providing a header for a combine harvester with a primary implement and a secondary implement for which the risk of damage to this secondary implement when moving over impediments is reduced and the header can be better transported on the road.

SOLUTION

According to the invention, the problem is solved by the features of the independent claims.

Further preferred embodiments according to the invention can be found in the dependent claims.

DESCRIPTION OF THE INVENTION

The invention concerns a header for a combine harvester with a primary implement and a secondary implement. The secondary implement has a roller unit. The roller unit has a frame element, an outer roller set with a rotatably supported roller and a central roller set with a rotatably supported roller. The central roller set is guided on the frame element to be lowerable relatively to the external roller set.

The invention further concerns a secondary implement for a combine harvester with such a roller unit, and such a roller unit.

BACKGROUND

In particular, the primary implement can be the main cutting unit of the combine harvester. So, for instance, it can be a grain or a maize cutting unit. In particular, the secondary implement can be a mowing unit, a cutting unit, or a swathing unit.

The secondary implement is arranged further to the rear of the header of the combine harvester than the primary implement. This means that during normal operation in the forward travel of the combine harvester, first the primary implement fulfils its function, and after further movement, the secondary implement fulfils its function. In normal operation, the movement of the secondary implement is arranged such that it moves parallel to the ground. This ensures an even processing of the ground.

In the case that impediments—e.g. deep ground undulations, trenches, rocks, etc.—must be crossed, the whole header, including the two implements, is lifted. However, if the header is one that is used for the so-called “high-cut” operation, there is the problem that, although the primary implement has been lifted up sufficiently high to pass over the impediment, the secondary implement, which is much closer to the ground, is too low for this. Thus, there is the danger of damage to the secondary implement when passing over the impediment.

A similar problem emerges during road transport of the header when it is dismounted from the combine harvester. When the header is separated from the combine harvester and loaded onto a trailer for road transport, then both implements attached to the harvester must be lifted over the wheels of the trailer. In the above described arrangement of displacement in the vertical direction of the two implements, the problem arises that, although the primary implement is arranged above the wheels, the secondary implement will still collide with them.

The header may further comprise a link coupled with the secondary implement. Now, to overcome the problems described above, the new header can comprise a lifting device with a slide element that is formed in such a manner and that is connected with the link so that a translational movement of the slide element causes with a lifting of the secondary implement relative to the primary implement. In this way, the height difference between the lowest point of the primary implement and the secondary implement is compensated in whole or at least in part. The header can be guided and loaded onto a trailer without the danger of a collision. In this way, the construction space available for the protected arrangement of the secondary implement can be optimally used.

The header has at its rear, as seen in the direction of travel, and in its centre an intake duct. The purpose of the intake duct is to take away the crop which have been cut by the primary implement and to feed it to a next processing step. It should be understood that the term “central zone” means the central plane in the longitudinal direction of the combine harvester and the header, perpendicular to the direction of travel. In other words, the central zone means the zone of the axis of symmetry of the header, extending outwardly in both directions. This central zone is to be distinguished from both outer zones on both sides of the combine harvester.

The bottom of the intake duct is already arranged to be very low—i.e. relatively close to the ground. Furthermore, piston-cylinder units are disposed in this area to lift or lower the complete header.

When the secondary implement, after raising the complete header by means of the lifting device, is lifted with respect to the primary implement to position the cutting unit of the primary implement into a protected lifted position, then the problem arises of a possible collision of the central set of rollers with the previously described piston-cylinder units and/or the intake duct.

Further Description

This problem will be overcome by lowering the central roller set with respect to the outer roller set when the header is lifted.

The secondary implement comprises besides its main device—more particularly its sickle bar with the reciprocatingly driven or rotating knives with a plurality of blades—also a roller unit that is arranged, as seen in the direction of travel, behind the blades and farther under the blades. This roller unit may comprise at least two—and preferably three—roller sets. The invention relates to the outer roller sets and the central roller set. Each roller set comprises at least one roller and preferably two rollers. The rollers are rotatably supported, and contact the ground in the operational position of the combine harvester. In this way, the desired parallel guidance of the blades of the secondary implement—i.e. the desired guidance of the blades with respect to the ground—is guaranteed. Besides its guide function, the roller unit can also have a further processing function for the cut crop and/or the ground, as is described in the international patent application WO 2013/011138 A1 of the applicants.

With such a secondary cutting unit, the blades constitute the sensitive parts and thus the parts that needs to be protected. The aim of lifting of the secondary implement relative to the primary implement is therefore to arrange the blades of the cutting unit in such a manner that they are positioned above a collision line. It is therefore preferable to lift the secondary implement relative to the primary implement so that the blades are arranged above the lowest point of the primary implement. So, the exposure of the secondary cutting unit is more a matter of this relative arrangement and less of the arrangement of the lowest point of the roller unit of the secondary implement.

This desired protected arrangement of the secondary implement—and particularly of its sensitive parts—is achieved by a suitable displacement of the slide element which connects the lifting device with the link. The lifting device is fixedly connected to the primary implement. In this respect, ‘connected’ means either through a direct connection or an indirect connection with an interposition of further components. In turn, the lifting device is connected via a link bearing and a coupling part—and possibly further components to the link. In turn, the link is connected either directly or indirectly via interposition of further components to the secondary implement. The secondary implement is also connected in its entirety to the primary implement wherein at least the lifting device and the link are interposed.

Thus, the part of the secondary implement to be shielded can be lifted by means of the new lifting device and in this way a less vulnerable part in the zone of the central plane in the longitudinal direction of the header can be lowered automatically. The central roller set swings or pivots downwards, when the header is lifted.

In this way, the central roller set is particularly mounted and guided on the frame element to automatically take the lowered position, when the roller of the central roller set is released from the ground during the lifting of the header. Thus, the lowering operation starts with the release of the roller from the ground and continues during the rest of the lifting movement of the header until the maximally lowered position of the central roller set has been reached. Then, the secondary implement can be lifted by means of the lifting means with respect to the primary implement, without causing a collision between parts.

In particular, the central roller set can take the lowered position by means of gravity only. This means that there is no need for an actuating device for this movement, but that the central roller set is arranged such that it can move sufficiently freely, under the influence of gravity and without being supported by the ground, to take the lowered position.

The central roller set can comprise a guiding element. The frame element can comprise a guiding slot, the guiding element engaging in the guiding slot and thus defining the path of movement of the central roller set. The guiding slot can have the form of an arc of a circle. Also a linear form is possible. The engaging of the guide element in the guiding slot ensures the reaching of the desired position of the roller set also when relatively high forces act on the roller set. In particular, this concerns the movement of the roller set from the lowered position into the operational position. This movement takes places automatically when the header is lowered resulting in the contact of the central roller with the ground. In this way, the guide also ensures that the pivot bearing of the central roller unit will not be damaged.

The secondary implement can comprise a cutting unit or another functional unit (hereafter collectively generalised and called “processing unit”), that processes crop and/or tills the ground. The processing unit is positioned in the driving direction of the roller unit. Consequently, the processing unit is guided by the roller unit parallel to the ground. Now, the central roller set can be supported rotatably by a bearing that is arranged under the processing unit and at a certain distance from the central roller set. In this manner, the central roller set is also supported by the guiding element and the bearing. Preferably, the bearing is arranged on the processing unit to also provide a stabilizing connection between the roller set and the processing unit.

The central roller set can have two side plates, the roller being arranged between the side plates. When the roller set has a plurality of rollers, these are arranged between the side plates. In addition, intermediate plates can be mounted between the rollers. Both side plates are generally L-shaped and have a first limb and a second limb. On both side plates, a guide element and a bearing are mounted. The guide element is mounted on the first limb—and in particular at the end region thereof—and the bearing is mounted on the second limb—and in particular at the end region thereof. The guiding elements engage in the corresponding guiding slot of the frame element and hence provide the desired guiding of the roller set during the swivelling movement along the path of the guiding slot. In this way, the central roller set is supported rotatably by the bearing on the other limb. Jointly, this results in a pendulum bearing of the central roller set.

The roller unit can comprise a second outer roller set with a rotatably supported roller. The central roller set is thus mounted between the outer roller sets. But, also further intermediate roller sets can be mounted. Every roller set can have one, two or more rollers. Preferably, the roller sets are modular, to enable them to be combined to form different working widths.

The invention also relates to a secondary implement for a combine harvester with a processing unit and a roller unit. The roller unit has a frame element, an external roller set comprising a rotatably supported roller, and a central roller set comprising a rotatably supported roller. The central roller set is guided on the frame element to be lowerable with respect to the outer roller set and the cutting unit. In particular, the secondary implement and the roller unit can be designed as described above in more detail.

The invention further relates to a roller unit for a header for a secondary cutting unit for a combine harvester. The roller unit has a frame element, an external roller set with a rotatably supported roller and a central roller set with a rotatably supported roller. The central roller set is guided on the frame element to be lowerable relatively to the external roller set. In particular, the roller unit can be designed as described above.

Advantageous developments of the invention are found in the claims, the description and the drawings. The advantages of the features and of combinations of several features mentioned in the description are only examples and can be effective alternatively or cumulatively without the advantages having to be achieved according to the present embodiments. Without the object of the appended claims being changed, the following applies, according to the disclosure of the original application documents and the patent: further features can be taken from the drawings—in particular, the depicted geometries and the relative dimensions of several components together as well as their relative arrangements and operational connections. The combination of features of different embodiments of the invention or of features of various claims also deviates from the selected references of the claims and is hereby proposed. This also applies to such features that are shown in separate drawings or that are mentioned in their description. These features can also be combined with features of various claims. Also the features mentioned in the claims, can be used for further embodiments of the invention.

The features mentioned in the claims and in the description are to be understood as regards their quantity, that exactly this quantity or a larger quantity than that mentioned is available without the requirement of an explicit use of the “at least” adverb. Therefore, when, for instance the term roller set is used, it is to be understood that exactly one roller set, two roller sets, or several roller sets are provided. These features can also be supplemented with other features or can be the only ones that make up the respective apparatus.

The reference numbers contained in the claims do not represent a limitation of the scope of the protected objects of the claims. Their purpose is solely to clarify the claims.

DESCRIPTION OF THE FIGURES

FIGS. 1-7show various views of an exemplary embodiment of a combine harvester1with a new header2. When the respective figure shows a rear view or view from the rear, then it is to be understood that the respective view is seen when looking in the direction of travel4from the rear. This is applies to the other Figures. Only the front portion of the combine harvester1is shown, as the remainder of the combine harvester1has no importance for this invention.

The combine harvester1can be driven, and for this purpose has several wheels of which these figures only show the front wheels3. In order to carry out its work, the combine harvester1travels in the direction of travel4over the ground5. As the wheels tend to sink into the ground5and the tires deform, the depiction is simplified in such a manner that the lower part of the front wheels3are shown here as being below the ground5.

The combine harvester1has a primary implement6, which is its main cutting implement and serves for the actual harvesting process. The primary implement6defines the working width7of the combine harvester1perpendicularly to the direction of travel4. The primary implement6itself is not an object of the present application and is thus not described in detail below.

FIGS. 1-7show various views of the operating conditions of the header2.FIGS. 1 and 2show the operational position,FIGS. 3 and 4a partly lifted position, and theFIGS. 5 and 6the completely lifted position.FIG. 7shows a perspective view of the header2in its operational position.

In order to improve the legibility of the drawings, not all reference signs have been reproduced in all drawings. This concerns mainly the repeated representation of identical components in different positions.

Secondary Implement

Besides the primary implement6, the combine harvester1has a, in particular modularly designed, secondary implement8. In this embodiment, it is designed as a cutting unit and serves for cutting the crop stubbles of the cut crop left standing by the primary implement6on the ground5. When moving the combine harvester1in the direction of travel4, therefore, the crops are first cut by the primary implement6at a greater height above the ground5. Then during the further travel all the remaining stubbles are cut down and/or up by the secondary implement8nearer to the ground5.

The secondary implement8has a roller unit9with a plurality—here, three—of roller sets10. In the present case, each roller set10has two rollers11, but could also have more or fewer rollers11. The secondary implement8therein is supported on the ground5by means of the roller unit9and/or is moved by this unit during the harvesting operation of the combine harvester1. The rollers11are designed in a cage-like manner and, in particular, consist of metal. The rollers11provide the secondary implement8with a good guidance, also in the case of difficult soil conditions—e.g. rocks, holes, slopes, etc.

The secondary implement8, here configured as a cutting unit, has knife bars with blades12attached thereto. The cutting unit, and particularly the blades12, can be easily damaged, which, however, is prevented by what is described below.

The secondary implement2is connected to a link13. The link13here is shown as an upper link14. Also a lower link15is provided for further fixing.

Lifting Device

The new header2has a lifting device16that is designed and connected by means of a link bearing17to the link13, such that a translational movement of the link bearing17causes a lifting of the secondary implement8relative to the primary implement6.

For this purpose, the lifting device16has an actuating device18which is designed here as a piston-cylinder unit19. The piston-cylinder unit19has a piston35that is driven to make a reciprocating movement in a cylinder36. This piston-cylinder unit19, through the translational movement of the piston35, causes a translational movement of the secondary implement8so that it is lifted up.

FromFIGS. 1 and 2it can be seen that, in the operating condition of the combine harvester1shown here, the secondary implement8is located substantially below primary implement6and thus nearer to the ground. This enables the cutting down of the stubbles left standing by the primary implement6.

Now, if the header2is brought into the lifted position shown inFIGS. 4 and 6, then the distance between the lower surface of the primary implement6and the ground5is sufficient for passing over trenches and similar impediments. But, as the secondary implement8is situated much lower, there is a risk of damage.

In order to prevent this type of damage, the secondary implement8can now be lifted relative to the primary implement6and brought into its lifted position as shown inFIGS. 5 and 6. In this position, the sensitive part of the cutting unit and, in particular, the blades12are positioned at a level above the lower exterior surface of the primary implement6, so that the blades12are protected when crossing impediments by this lower exterior surface.

FIGS. 8-10show various views of an embodiment of the lifting device16. In the described example, the header2has two lifting devices16of this type, which are provided to the header2. But it could also be provided with only one lifting device16, or also three or more lifting devices16.

The lifting device16has a slide element20and a stop or contact point21that is here formed as a pin. The gravity dependent contact with the link13passes over said contact point21. The permanently rotatable connection between the link13and the lifting device16is achieved by means of a coupling part22and the link bearing17. The coupling part22is rotatably connected via the link bearing17to the slide element20.

The slide element20has guide elements23that are designed here as guide rollers24. But, for example, these could also be pins. The guide elements23engage in a guiding slot25of a guide component26. The guide component26is fastened to the rear side of the primary implement6.

Safety Device

The lifting device16further has a safety device27. The safety device27has a safety latch28, a safety slot29and a safety spring30. The safety spring30presses the safety latch28into the safety slot29, while the safety latch28is rotatably connected via a bearing31with the slide element20. Herein, the safety latch28is connected to a safety pin32, which then finally sits in the safety slot29.

The slide element20further has a track-shaped release slot33which guides a pin34. The pin34is connected with the actuating device18as well as with the safety latch28.

FIGS. 8-11show the safety position of the safety device27of the lifting device16.

The secondary implement8touches the ground5and the link13is not touching the contact point21. In this way, no weight force is transferred. The safety spring30presses the safety latch28with its safety pin32into the safety slot29. The actuating device18is situated in its lowered position and the pin34is situated in the lower region of the release slot33.

The safety device27further has a release position, a released position, a partly lifted position and a maximal lifted position, but these are not described in more detail in the present application.

Lowerable Central Roller Set

As shown in particular inFIGS. 12-26, the new header2for the combine harvester1is designed to lower the central roller set10with respect to the—in this embodiment—two outer roller sets10, when the header is lifted.

The secondary implement8has several frame elements37, which, collectively, form a frame38of the roller unit9and are connected to the primary implement6by means of the links13,15and the lifting device16. In addition to the roller unit9, the secondary implement8has a cutting unit39. Here the cutting unit39is formed exactly by a knife bar with upper and lower knives, extending over the entire working width7of the secondary implement8. But, the knife bar also could be modular. The implement8may also comprise another processing unit.

As shown in particular inFIG. 15, the central roller set10has two side plates40, with the rollers11arranged in between. Hence, these side plates40limit and define the respective roller set10. Between the rollers11of the roller set10an intermediate plate41has been mounted (seeFIG. 16). Both side plates10are generally L-shaped and have a first limb42and a second limb43. On the first limb42, a guide element44is mounted, that, for instance, can be designed as a guide pin or as a guide roller. On the second limb43, a bearing45is mounted, that, for instance, can be designed as a pivot bearing. In this way, the bearing45is arranged under the cutting unit39and at a certain distance from the rollers11.

The segment of the frame element37provided near both side plates40has a guiding slot46. The guiding slot46has the form of an arc of a circle, but, it also could have another shape. The guide element44engages in the guiding slot46of the frame element37and can be moved therein under certain conditions. Doing this, the roller unit10pivots about the bearing45. InFIG. 15it can be seen that the guide element44has been positioned at the upper end stop of the guiding slot46. This means that the roller set10is not lowered, as is the case when the roller unit9of the secondary implement8is resting on the ground5.

Now,FIGS. 17-23show the roller set10in its lowered position. It can be seen that the guide element44now is at the lower stop of the guiding slot46. This means that the guide element44has traversed the guiding slot46, while the roller unit10has pivoted about bearing45and has been lowered with respect to the other roller sets10. This is the case when the secondary implement8has been lifted and the roller unit9is not supported on the ground anymore.

FIG. 22shows in its left half the left end of an outer roller set10—seen from the front—and in its right half, the nearby arranged right end of the lowered central roller set10.

FIG. 23shows in its left half the right end of the lowered central roller set10—seen from the rear—and, nearby, in its right half, the left end of the outer central roller set10.

InFIGS. 27-29and inFIG. 29in particular, it can also be seen that the neighbouring roller sets10are connected together by means of a buffer element47. Preferably, the buffer element47is made of rubber, plastic or another elastic material to allow some relative movement between the roller sets10without causing damage.