Abstract:
A harvesting machine including an engine and a grain threshing system driven by the engine. The grain threshing system includes at least one rotating member, at least one concave, a torque measuring device and an adjustment mechanism. The at least one rotating member receives a torque from the engine. The at least one concave is proximate to the at least one rotating member. The torque measuring device is coupled to the rotating member or the engine. The torque measuring device produces a signal related to the torque applied to the rotating member. The adjusting mechanism is coupled to the at least one concave. The adjusting mechanism is configured to position the at least one concave relative to the at least one rotating member dependent upon the signal.

Description:
[0001]    The present invention relates to a threshing mechanism, and more particularly, to a threshing mechanism in a harvesting vehicle. 
       BACKGROUND OF THE INVENTION 
       [0002]    A grain harvesting vehicle, also known as a combine, includes a header, which cuts the crop and feeds 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 of the grain from the crop matter directed thereinto. Once the grain is threshed it falls through perforations in the concaves onto a grain pan. From the grain pan the grain falls through a set of sieves that vibrate and/or oscillate causing the clean grain to fall through the sieves for collection of the grain and the removal of the chaff and/or other debris. A cleaning fan blows air through the sieves to discharge the chaff towards the rear of the combine. Crop residue such as straw from the threshing section proceeds through a straw chopper and out the rear of the combine. 
         [0003]    Grain losses, grain damage, fuel consumption and performance of a combine is related to how well the operator has set the various adjustable elements of the combine in order to provide optimal results for the intended crop and crop conditions. One of the elements that require adjustment include the rotor speed and the concave clearance for the threshing rotor. The adjustment that the operator makes offers opportunity for either good or poor results based upon the adjustments. If the rotor speed and concave clearance are set correctly, the grain can be threshed efficiently with little damage, minimal losses and optimal fuel usage. If the rotor/concave clearance is set too tight and the rotor speed is too high for the conditions, severe grain damage may result and excessive threshing power will be utilized, which can lead to lost productivity and poor fuel economy. If the concave is set too wide and the rotor speed is too low, the grain may not be threshed out properly, resulting in excessive losses out the back of the combine. 
         [0004]    Currently the setting of the concave clearance and speed of the rotor is accomplished by trial and error, by the running of the combine for a short period of time, such as 30 seconds or a minute with initial “book” settings, then the crop residue is checked behind the combine and also the grain in the grain tank is checked for losses and damage to the grain. If the settings for the rotor speed or the concave clearance is changed then another trial run is repeated. Currently performance and fuel economy are difficult to evaluate except in comparison to other machines and by long term fuel consumption measurements. 
         [0005]    What is needed in the art is a cost effective, economical way of determining if the rotor and concave settings are correct for the harvesting conditions. 
       SUMMARY OF THE INVENTION 
       [0006]    The present invention provides a way to control and the concave settings in a harvesting machine based on torque being applied to the rotor. 
         [0007]    The invention in one form is directed to a harvesting machine including an engine and a grain threshing system driven by the engine. The grain threshing system includes at least one rotating member, at least one concave, a torque measuring device and an adjustment mechanism. The at least one rotating member receives a torque from the engine. The at least one concave is proximate to the at least one rotating member. The torque measuring device is coupled to the rotating member or the engine. The torque measuring device produces a signal related to the torque applied to the rotating member. The adjusting mechanism is coupled to the at least one concave. The adjusting mechanism is configured to position the at least one concave relative to the at least one rotating member dependent upon the signal. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]      FIG. 1  is an illustrated vehicle utilizing an embodiment of the grain threshing system of the present invention; 
           [0009]      FIG. 2  is a schematical diagram of elements of the grain threshing system of the present invention; and 
           [0010]      FIG. 3  is a flow chart illustrating steps of an embodiment of a method of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0011]    Referring now to the drawings, and more particularly to  FIG. 1 , there is shown a harvesting machine  10  having a chassis  12  supported by wheels  14 . A grain threshing assembly  16  receives crop matter containing grain that is gathered by a head mechanism on harvester  10 . Grain threshing assembly  16  includes a rotor  20  that is driven by engine  18 . Rotor  20  is positioned proximate to concaves  22 , which allow grain to fall through openings in concaves  22  that has been loosened from the crop matter by the rotating action of rotor  20 . Concaves  22  are curved to correspond to the shape of rotor  20  and concaves  22  are positioned by an adjusting mechanism  24 , also known as an actuator  24 , to properly position concaves  22  relative to rotor  20 . Grain threshing assembly  16  further includes a torque sensor  26 , a shaft  28  and a controller  30 . 
         [0012]    Now, additionally referring to  FIG. 2 , there is shown a schematical diagram that include elements of grain threshing assembly  16  including sensors  26  and  34 , a display  36  and operator controls  38 . As crop matter enters grain threshing assembly  16 , rotor  20  is powered by engine  18  by way of shaft  28  to provide a rotational torque to rotor  20 . For the ease of understanding the invention, the mechanism coupling engine  18  to rotor  20  is described as a shaft  28 , the coupling that drives rotor  20  may be in another form, such as a hydraulic motor that is supplied a hydraulic fluid pressure from a pump connected to engine  18 . A torque sensor  26  is connected either to shaft  28  or is associated with either rotor  20  or engine  18  to provide a signal to controller  30  that relates to the torque being used to drive rotor  20  as it threshes crop matter between rotor  20  and concaves  22 . Torque sensor  26  may be of any form to provide a signal that is representative of the torque used to drive rotor  20 . For example torque sensor  26  may be a strain gauge, a measurement of the torsional flex of shaft  28  or some other method of measuring torque. Torque sensor  26  also provides speed information on the speed at which rotor  20  is being driven. Controller  30  is tasked to adjust concaves  22  by way of actuator  24  based upon the torque and speed information provided from sensor  26 . Actuator  24  may be in the form of a hydraulic actuator, an electrical actuator, a pneumatic actuator or even a combination of these forms in order to position concave  22  at a desired position relative to rotor  20  for the optimal threshing of grain. Sensor  34  provides positional information, of concaves  22  relative to rotor  20 , to controller  30 , also known as concave clearance. A display  36  provides a visual display of the concave clearance information as well as torque and speed of rotor  20  so that the operator can, by way of operator controls  28 , provide adjusting information to controller  30  for the control of the positioning of concaves  20 , and also allows the operator to adjust the engine and/or rotor speed. 
         [0013]    Now, additionally referring to  FIG. 3 , there is shown a flowchart that illustrates the steps involved in the present invention. Method  100  includes steps  102 - 112 . At step  102  performance attributes of rotor  20  are measured, which may include the torque that is required to drive rotor  20  as well as the speed of rotor  20  and even other attributes such as vibrational characteristics. The attributes are displayed at step  104  on display  36  to provide an operator information relative to the performance of rotor  20 . The attributes measured at step  102  are compared to expected and/or desired attributes at step  106  by controller  30 . As a result of the comparison undertaken at step  106  suggested adjustments are visually illustrated on display  36 , at step  108  to the operator, so that the operator may make an informed decision as to any adjustments in the commanded performance of rotor  20  that may be necessary. The performance of rotor  20  is adjusted at step  110 , which may include changes of speed or available torque to rotor  20 . Additionally, at step  112 , the concave clearance may be adjusted by having actuator  24  reposition concaves  22  relative to rotor  20 . This action of either decreasing or increasing the clearance between concaves  22  and rotor  20  alter the performance of harvester  10  as it gathers and separates grain. 
         [0014]    Advantageously the invention measures torque supplied to rotor  20  as well as the speed by way of sensor  26 , which is connected to a controller  30 . Controller  30  may be assimilated within a controller used for other functions in combine  10 , or may be a separate controller, as illustrated herein for the ease of understanding. The torque computed by controller  30  is displayed on display  36  in the cab in the form of a gauge that informs the operator how much power is being consumed by rotor  20 . Display  36  may display power in horsepower or kilowatts and may also have a needle or indicator that points to a zone of efficient operation for easy reference while operating harvesting machine  10 . For example, an optimal zone of performance on display  36  could be green in color. The operator would drive and operate harvester  10  to keep the indicator in the green, or the power in kilowatts within a expected power range for the conditions being encountered. 
         [0015]    Controller  30  can also receive inputs from operator controls  38  to indicate to controller  30  the type of crop being harvested, such as corn, wheat or soybeans. Other sensors can also be coupled to controller  30  to measure the grain moisture and feed rate of the crop matter coming into harvester  10 . Controller  30  can use specific threshing power coefficients determined during field testing and computational algorithms to compute the expected power consumption for the given grain type, moisture content of the grain and or crop matter, and feed rates of the crop matter. If the power being consumed by rotor  20  falls outside of an expected power range for these conditions, then display  36  would show the power being consumed and the indicator would be moved away from the green condition to indicate a sub-optimal performance. Display  36  offer suggestions at step  108  for concave clearance and rotor speed, which the operator can change while continuing to operate harvester  10 . This advantageously precludes the need to stop and look behind the combine or check a new grain sample from the grain bin. Rather, the operator can change the settings and then immediately check the impact on rotor power for confirmation as to the correctness of the settings as compared to the experience validated during field testing. 
         [0016]    Additionally, controller  30  may be enabled to automatically adjust the concave clearance in response to the consumed rotor power automatically. If the power demand increases in response to higher feed rates, concaves  22  can be opened slightly to permit the higher volume of material to pass through without taking excessive power to drive rotor  20 . In light load conditions, the concave clearance is reduced to automatically maintain good threshing with the lighter crop material flow. In this way, threshing system can automatically adjust to varying crop yields as the machine travels across the field. This also allows the maintaining of high threshing efficiency as conditions vary, reducing power consumption and reducing grain losses. 
         [0017]    The operator may, by way of operator controls  38 , disable the automatic function to stop the automatic concave adjustment function. Additionally, the operator can key-in a range of automatic adjustments to enable system  16  to adjust but only to the specified degree relates to the range input by the operator. The present invention enables quick and accurate power monitoring of threshing rotor  20  while harvesting and verification that the concave clearance and the rotor speed settings conform to the given crop, moisture and feed rate conditions compared to what is determined for harvester  10  as optimal elements for performance for fuel consumption, grain loss and damage. This allows machine  10  to operate near optimal settings while reducing wear and tear on the threshing elements. This system can additionally learn from the adjustments undertaken manually to automatically make the required adjustments to maximize field performance. 
         [0018]    Having described the preferred embodiment, it will become apparent that various modifications can be made without departing from the scope of the invention as defined in the accompanying claims.