AGRICULTURAL HARVESTER WITH SHAKEABLE POSITIVE TRANSPORT CONVEYOR

A cleaning system for an agricultural harvester includes: at least one sieve; a cleaning blower directed at the at least one sieve and configured to supply a cleaning air flow directed at the at least one sieve; and a conveyor assembly configured to supply crop material to the at least one sieve. The conveyor assembly includes: a conveyor frame; a shaker coupled to the conveyor frame and configured to shake the conveyor frame; and an endless conveyor carried by the conveyor frame and including a conveyor loop with a substantially solid surface and a conveyor driver coupled to the conveyor loop, the conveyor driver being configured to selectively rotate the conveyor loop.

FIELD OF THE INVENTION

The present invention pertains to an agricultural harvester and, more specifically, to a conveyor assembly for an agricultural harvester.

BACKGROUND OF THE INVENTION

An agricultural harvester known as a “combine” is historically termed such because it combines multiple harvesting functions with a single harvesting unit, such as picking, threshing, separating, and cleaning. A combine includes a header which removes the crop from a field, and a feeder housing which transports the crop matter into a threshing rotor. The threshing rotor rotates within a perforated housing, which may be in the form of adjustable concaves, and performs a threshing operation on the crop to remove the grain. Once the grain is threshed it falls through perforations in the concaves onto a grain pan. From the grain pan the grain is cleaned using a cleaning system, and is then transported to a grain tank onboard the combine. A cleaning fan or similar element blows air through the sieves to discharge chaff and other debris toward the rear of the combine. Non-grain crop material such as straw from the threshing section proceeds through a residue handling system, which may utilize a straw chopper to process the non-grain material and direct it out the rear of the combine. When the grain tank becomes full, the combine is positioned adjacent a vehicle into which the grain is to be unloaded, such as a semi-trailer, gravity box, straight truck, or the like, and an unloading system on the combine is actuated to transfer the grain into the vehicle.

More particularly, a rotary threshing or separating system includes one or more rotors that can extend axially (front to rear) or transversely (side to side) within the body of the combine, and which are partially or fully surrounded by perforated concaves. The crop material is threshed and separated by the rotation of the rotor within the concaves. Coarser non-grain crop material such as stalks and leaves pass through a straw beater to remove any remaining grains, and then are transported to the rear of the combine and discharged back to the field. The separated grain, together with some finer non-grain crop material such as chaff, dust, straw, and other crop residue are discharged through the concaves and fall onto a grain pan where they are transported to a cleaning system. Alternatively, the grain and finer non-grain crop material may also fall directly onto the cleaning system itself.

A cleaning system further separates the grain from non-grain crop material, and typically includes a fan directing an airflow stream upwardly and rearwardly through vertically arranged sieves which oscillate in a fore and aft manner. The airflow stream lifts and carries the lighter non-grain crop material towards the rear end of the combine for discharge to the field. Clean grain, being heavier, and larger pieces of non-grain crop material, which are not carried away by the airflow stream, fall onto a surface of an upper sieve (also known as a chaffer sieve), where some or all of the clean grain passes through to a lower sieve (also known as a cleaning sieve). Grain and non-grain crop material remaining on the upper and lower sieves are physically separated by the reciprocating action of the sieves as the material moves rearwardly. Any grain and/or non-grain crop material which passes through the upper sieve, but does not pass through the lower sieve, is directed to a tailings pan. Grain falling through the lower sieve lands on a bottom pan of the cleaning system, where it is conveyed forwardly toward a clean grain auger. The clean grain auger conveys the grain to a grain elevator, which transports the grain upwards to a grain tank for temporary storage. The grain accumulates to the point where the grain tank is full and is discharged to an adjacent vehicle such as a semi trailer, gravity box, straight truck or the like by an unloading system on the combine that is actuated to transfer grain into the vehicle.

Crop material flow rate within the agricultural harvester depends on a variety of factors. When the harvester travels through an area of a field that is densely occupied by crop material, the crop material flow rate increases, and vice versa. Non-uniform crop material flow rate into the harvester can affect the efficiency of the harvester due to, for example, sudden influxes of crop material overwhelming certain systems within the harvester. Periods of low crop material flow can also detrimentally affect efficiency of the harvester due to crop material not moving efficiently within the harvester.

What is needed in the art is an agricultural harvester that can address one or more of the previously described issues with known agricultural harvesters.

SUMMARY OF THE INVENTION

Exemplary embodiments disclosed herein provide a cleaning system for an agricultural harvester with an endless conveyor that is carried by a conveyor frame coupled to a shaker and has a conveyor driver that can selectively rotate a conveyor loop.

In some exemplary embodiments provided according to the present disclosure, a cleaning system for an agricultural harvester includes: at least one sieve; a cleaning blower directed at the at least one sieve and configured to supply a cleaning air flow directed at the at least one sieve; and a conveyor assembly configured to supply crop material to the at least one sieve. The conveyor assembly includes: a conveyor frame; a shaker coupled to the conveyor frame and configured to shake the conveyor frame; and an endless conveyor carried by the conveyor frame and including a conveyor loop with a substantially solid surface and a conveyor driver coupled to the conveyor loop, the conveyor driver being configured to selectively rotate the conveyor loop.

In some exemplary embodiments provided according to the present disclosure, an agricultural harvester includes: a chassis; a threshing and separating system carried by the chassis, the threshing and separating system including a threshing rotor that is rotatable within a concave; and a cleaning system including: at least one sieve; a cleaning blower directed at the at least one sieve and configured to supply a cleaning air flow directed at the at least one sieve; and a conveyor assembly configured to supply crop material to the at least one sieve. The conveyor assembly includes: a conveyor frame; a shaker coupled to the conveyor frame and configured to shake the conveyor frame; and an endless conveyor carried by the conveyor frame and including a conveyor loop with a substantially solid surface and a conveyor driver coupled to the conveyor loop, the conveyor driver being configured to selectively rotate the conveyor loop.

One possible advantage that may be realized by exemplary embodiments provided according to the present disclosure is that the conveyor assembly may act as a shaking grain pan when the conveyor driver is not rotating the conveyor loop but also provide positive crop material transport when the conveyor driver selectively rotates the conveyor loop.

Another possible advantage that may be realized by exemplary embodiments provided according to the present disclosure is that the conveyor driver can be controlled to adjust positive crop material transport responsively to different harvesting conditions.

DETAILED DESCRIPTION OF THE INVENTION

The terms “grain”, “straw” and “tailings” are used principally throughout this specification for convenience but it is to be understood that these terms are not intended to be limiting. Thus “grain” refers to that part of the crop material which is threshed and separated from the discardable part of the crop material, which is referred to as non-grain crop material, MOG or straw. Incompletely threshed crop material is referred to as “tailings”. Also, the terms “forward”, “rearward”, “left” and “right”, when used in connection with the agricultural harvester and/or components thereof are usually determined with reference to the direction of forward operative travel of the harvester, but again, they should not be construed as limiting. The terms “longitudinal” and “transverse” are determined with reference to the fore-and-aft direction of the agricultural harvester and are equally not to be construed as limiting. The terms “downstream” and “upstream” are determined with reference to the intended direction of crop material flow during operation, with “downstream” being analogous to “rearward” and “upstream” being analogous to “forward.”

Referring now to the drawings, and more particularly toFIG.1, there is shown an embodiment of an agricultural harvester100in the form of a combine which generally includes a chassis101, ground engaging wheels102and103, header110, feeder housing120, operator cab104, threshing and separating system130, cleaning system140, grain tank150, and unloading conveyance160. Front wheels102are larger flotation type wheels, and rear wheels103are smaller steerable wheels. Motive force is selectively applied to front wheels102through a power plant in the form of a diesel engine105and a transmission (not shown). Although combine100is shown as including wheels, is also to be understood that combine100may include tracks, such as full tracks or half tracks.

Header110is mounted to the front of combine100and includes a cutter bar111for severing crops from a field during forward motion of combine100. A rotatable reel112feeds the crop into header110, and a double auger113feeds the severed crop laterally inwardly from each side toward feeder housing120. Feeder housing120conveys the cut crop to threshing and separating system130, and is selectively vertically movable using appropriate actuators, such as hydraulic cylinders (not shown).

Threshing and separating system130is of the axial-flow type, and generally includes a threshing rotor131at least partially enclosed by a rotor cage and rotatable within a corresponding perforated concave132. The cut crops are threshed and separated by the rotation of rotor131within concave132, and larger elements, such as stalks, leaves and the like are discharged from the rear of combine100. Smaller elements of crop material including grain and non-grain crop material, including particles lighter than grain, such as chaff, dust and straw, are discharged through perforations of concave132. Threshing and separating system130can also be a different type of system, such as a system with a transverse rotor rather than an axial rotor, etc.

Grain which has been separated by the threshing and separating assembly130falls onto a conveyor assembly133, which is part of cleaning system140. Cleaning system140may include an optional pre-cleaning sieve141, an upper sieve142(also known as a chaffer sieve or sieve assembly), a lower sieve143(also known as a cleaning sieve), and a cleaning blower144, which may be a fan or similar element. Grain on sieves141,142and143is subjected to a cleaning action by blower144which provides an air flow through the sieves to remove chaff and other impurities such as dust from the grain by making this material airborne for discharge from a straw hood171of a residue management system170of combine100. Optionally, the chaff and/or straw can proceed through a chopper180to be further processed into even smaller particles before discharge out of the combine100by a spreader assembly200. It should be appreciated that the “chopper”180referenced herein, which may include knives, may also be what is typically referred to as a “beater”, which may include flails, or other construction and that the term “chopper” as used herein refers to any construction which can reduce the particle size of entering crop material by various actions including chopping, flailing, etc. Conveyor assembly133and pre-cleaning sieve141may oscillate in a fore-to-aft manner to transport the grain and finer non-grain crop material to the upper surface of upper sieve142. Upper sieve142and lower sieve143are vertically arranged relative to each other, and likewise oscillate in a fore-to-aft manner to spread the grain across sieves142,143, while permitting the passage of cleaned grain by gravity through the openings of sieves142,143.

Clean grain falls to a clean grain auger145positioned crosswise below and toward the front of lower sieve143. Clean grain auger145receives clean grain from each sieve142,143and from a bottom pan146of cleaning system140. Clean grain auger145conveys the clean grain laterally to a generally vertically arranged grain elevator151for transport to grain tank150. Tailings from cleaning system140fall to a tailings auger trough147. The tailings are transported via tailings auger147and return auger148to the upstream end of cleaning system140for repeated cleaning action. A pair of grain tank augers152at the bottom of grain tank150convey the clean grain laterally within grain tank150to unloader160for discharge from combine100.

In known agricultural harvesters, there are two widely utilized ways to convey crop material that has passed through the threshing and separating system to the cleaning system. One of the ways is to utilize a grain pan that shakes fore-to-aft and side-to-side to both convey the crop material rearwardly toward the cleaning system while also stratifying the crop material. The other way is to utilize a conveyor, such as a belt conveyor, to convey the crop material toward the cleaning system. Utilizing a grain pan desirably stratifies the crop material, which can make it easier to separate MOG from grain in the cleaning system, but is susceptible to changes in crop material flow rate. If the angle of inclination of the grain pan changes, for example, the crop material can pool or otherwise not efficiently convey across the grain pan to the cleaning system. A belt conveyor, on the other hand, can be controlled so the belt conveyor is less susceptible to changes in crop material flow rate but causes minimal stratification of the crop material.

To address some of the previously described issues with known agricultural harvesters, and referring now toFIGS.2-5, the conveyor assembly133is illustrated in further detail. The conveyor assembly133includes a conveyor frame210, a shaker220coupled to the conveyor frame210, and an endless conveyor230carried by the conveyor frame210. The shaker220is configured to shake the conveyor frame210, e.g., in a fore-to-aft direction FD and a lateral direction (extending into the page). The shaker220may be coupled to one or more frame members211of the conveyor frame210by, for example, one or more shaker arms221. The shaker arm(s)221may be coupled to a shaker driver222, e.g., an eccentric drive unit, to drive shaking movement of the conveyor frame210. Many arrangements of shakers suitable for use in agricultural harvesters, e.g., for shaking a grain pan of the harvester, are known, and any such shaker may be provided according to the present disclosure.

The endless conveyor230is carried by the conveyor frame210so movement of the conveyor frame210causes a corresponding movement of the endless conveyor230. The endless conveyor230includes a conveyor loop231including a substantially solid surface232and a conveyor driver233coupled to the conveyor loop231. The conveyor driver233may include a driven roller234and another roller235, which may or may not also be driven. As used herein, the surface232is “substantially solid” in the sense that the surface232is non-perforated to generally prevent air flow from passing through the surface232to blow out crop material, such as MOG. This is in contrast to, for example, one of the sieves141,142,143, which are perforated to allow air flow to pass therethrough and remove MOG. The conveyor loop231may be, for example, a belt.

The conveyor driver233coupled to the conveyor loop231is configured to selectively rotate the conveyor loop231. Selective rotation of the conveyor loop231by the conveyor driver233can speed up or slow down the rate of crop material being carried by the conveyor loop231, which may be a mixture of grain and MOG, towards the sieve(s)141,142,143. In this sense, there may be times during operation when the conveyor driver233is not rotating the conveyor loop231; in some embodiments, the conveyor driver233is not rotating the conveyor loop231during the majority of operation. When the conveyor driver233is not rotating the conveyor loop231, conveyance of crop material by the endless conveyor230may be due only to other types of movement, i.e., by the shaker220shaking the conveyor frame210to also shake the endless conveyor230. For example, the shaker220may be configured to shake the conveyor frame210in the fore-to-aft direction FD such that crop material is supplied to the sieve(s)141,142,143from the conveyor loop231without rotating the conveyor loop231, i.e., movement of the crop material by the endless conveyor230is due solely to the shaking action of the conveyor frame210and the carried endless conveyor230. The conveyor driver233may be activated selectively responsively to certain conditions to adjust movement of the crop material by the endless conveyor230, as will be described further herein.

During conveyance of crop material, the crop material may normally move in a first conveyance direction CD1during shaking of the conveyor frame210and the endless conveyor230. The first conveyance direction CD1may extend from a front end212of the conveyor frame210toward a rear end213of the conveyor frame210. The front end212of the conveyor frame210may be closer to the threshing and separating system130than the rear end213while the rear end213may be closer to the sieve(s)141,142,143than the front end212. In this sense, crop material normally moves in the first conveyance direction CD1from the threshing and separating system130to the sieve(s)141,142,143via the conveyor assembly133.

In some embodiments, and referring now toFIG.3as well, the surface232includes a plurality of rabbets330formed therein. Each of the rabbets330includes a pair of steps331that are coupled to one another by an angled portion332of the surface232. The steps331may define respective peaks332that help prevent crop material being conveyed in the first conveyance direction CD1from moving in a second conveyance direction CD2, which is opposite to the first conveyance direction CD1and extends from the rear end213of the conveyor frame210toward the front end212of the conveyor frame210. The rabbets330thus reduce the likelihood of crop material conveying in the second conveyance direction CD2back toward the threshing and separating system130to encourage crop material flow toward the sieve(s)141,142,143.

In some embodiments, a controller106(illustrated inFIG.1) is operably coupled to the conveyor driver233and configured to cause selective activation of the conveyor driver233to rotate the conveyor loop231. For example, the controller106may be configured to output electrical signals to the conveyor driver233to directly control selective activation of the conveyor driver233and thus selective rotation of the conveyor loop231by the conveyor driver233. The controller106may be configured, for example, to control the conveyor driver233to control a driving velocity of the conveyor loop231by the conveyor driver233. The driving velocity includes both the conveyance direction CD1, CD2of the conveyor loop231as well as a conveyance speed of the conveyor loop231. The controller106may control the conveyor driver233to rotate in a first rotation direction and a second rotation direction that is opposite the first rotation direction. Rotation of the conveyor driver233in the first rotation direction causes the conveyor loop231to rotate in the first conveyance direction CD1while rotation of the conveyor driver233in the second rotation direction causes the conveyor loop231to rotate in the second conveyance direction CD2. The controller106may control the conveyor driver233to rotate at any suitable conveyance speed to control the rotational speed of the conveyor loop231and thus the conveyance speed of crop material carried by the conveyor loop231.

Referring now toFIGS.4-5, it is illustrated how the controller106may control the conveyor driver233to selectively rotate the conveyor loop231and affect crop material movement across the endless conveyor230. The controller106may be configured to determine an angle of inclination of the conveyor frame210has changed and responsively cause a change in the driving velocity of the conveyor loop231by the conveyor driver233. The controller106may determine the angle of inclination has changed, for example, by being operably coupled to an inclination sensor107that is mounted to the conveyor frame210. The controller106may be configured to cause the driving velocity to increase responsively to determining the angle of inclination has changed so the rear end213of the conveyor frame210is raised above the front end212of the conveyor frame210, as illustrated inFIG.4, and/or cause the driving velocity to decrease responsively to determining the angle of inclination has changed so the front end212of the conveyor frame210is raised above the rear end213of the conveyor frame210. As used herein, the driving velocity is measured with respect to the first conveyance direction CD1so the driving velocity increases when the rotation speed of the conveyor loop231in the first conveyance direction CD1increases or the rotation speed of the conveyor loop231in the second conveyance direction CD2decreases. Conversely, the driving velocity decreases when the rotation speed of the conveyor loop231in the first conveyance direction CD1decreases or the rotation speed of the conveyor loop231in the second conveyance direction CD2increases.

As can be appreciated fromFIGS.4-5, the driving velocity of the conveyor loop231increasing can help overcome the additional effects of gravity on the crop material being conveyed so the crop material flow rate to the sieve(s)141,142,143does not decrease in situations where the agricultural harvester100is traveling, for example, downhill. The driving velocity of the conveyor loop231decreasing, on the other hand, can slow down the crop material flow rate to the sieve(s)141,142,143and reduce the risk of the sieve(s)141,142,143becoming overwhelmed when, for example, the agricultural harvester100is traveling uphill and gravity is forcing the crop material toward the sieve(s)141,142,143. The controller106may be configured, for example, to cause the conveyor driver233to rotate in the second rotation direction, which causes the conveyor loop231to rotate in the second conveyance direction CD2and slow down the crop material flow rate, responsively to determining the angle of inclination has changed so the front end212of the conveyor frame210is raised above the rear end213of the conveyor frame210by a defined amount, which can be an amount that corresponds to crop material flowing across the conveyor assembly133toward the sieve(s)141,142,143too quickly. It should thus be appreciated that controlling the driving velocity of the conveyor loop231can be responsive to changes in conditions that tend to increase or decrease the crop material flow rate to the sieve(s)141,142,143unless the conveyor driver233selectively activates to rotate the conveyor loop231. Selective activation of the conveyor driver233can thus help maintain a steady flow rate of crop material to the sieve(s)141,142,143from the threshing and separating system130via the conveyor assembly133.

In some embodiments, the controller106is configured to determine a feed rate of crop material to the conveyor assembly133and responsively control the conveyor driver233. A feed rate sensor108may be provided that is operably coupled to the controller106and configured to output a feed signal corresponding to the feed rate of crop material to the conveyor assembly133. The feed rate sensor108may be, for example, an optical sensor and/or a mass sensor. The controller106may be configured to determine the feed rate of crop material to the conveyor assembly133is greater than a defined value and responsively cause a decrease in the driving velocity of the conveyor loop231by the conveyor driver233, e.g., by causing the conveyor driver233to decrease its rotational speed in the first rotation direction or increase its rotational speed in the second rotation direction. The controller106may also be configured to determine the feed rate of crop material to the conveyor assembly133is less than a defined value and responsively cause an increase in the driving velocity of the conveyor loop231by the conveyor driver233, e.g., by causing the conveyor driver233to increase its rotational speed in the first rotation direction or decrease its rotational speed in the second rotation direction. In some embodiments, the controller106may be configured to determine the feed rate of crop material to the conveyor assembly133based on other parameters, including but not limited to crop moisture. In this respect, the controller106may control the conveyor driver233based on crop harvesting conditions, indicated by the feed rate of crop material to the conveyor assembly133, and/or based on other conditions that affect the flow rate of crop material within the agricultural harvester100, such as the angle of inclination of the conveyor frame210.

From the foregoing, it should be appreciated that the conveyor assembly133provided according to the present disclosure can normally shake to convey crop material, which encourages stratification, while also having a selectively activated conveyor driver233that can be activated to increase or decrease crop material conveyance by the conveyor assembly133. The conveyor driver233can be controlled in response to various conditions that occur during operation, allowing the crop material feed rate to the sieve(s)141,142,143to be appropriately controlled. Thus, the conveyor driver233can be controlled to encourage steady crop material feeding to the sieve(s)141,142,143by the conveyor assembly133and maintain efficient operation of the cleaning system140.

Referring now toFIG.6, an exemplary embodiment of a method600for controlling the cleaning system140of the agricultural harvester100is illustrated. The method600includes conveying601crop material in the first conveyance direction CD1toward at least one sieve141,142,143by shaking the conveyor frame210and the carried endless conveyor230with the shaker220. The method600further includes selectively rotating602the conveyor loop231with the conveyor driver233to increase or decrease the driving velocity of the conveyor loop231. In some embodiments, selectively rotating602the conveyor loop231with the conveyor driver233maintains a constant crop material feed rate to the sieve(s)141,142,143, relative to when the conveyor driver233is not driving rotation of the conveyor loop231. The method600may further include determining603that the conveyor loop231should be selectively rotated by, for example, the controller106or otherwise. The determining603may include, but is not limited to, determining the feed rate of crop material to the conveyor assembly133has changed and/or determining the angle of inclination of the conveyor frame210has changed.