Abstract:
A combine harvester has a threshing mechanism with a rotor and a plurality of concaves for threshing grain and cleaning apparatus for removing chaff from the threshed grain. The cleaning apparatus includes a rotor pan arranged below the concaves and a sieve arranged below the rotor pan. A fan is arranged to blow air into an inlet. A duct has a wall defining a passage in fluid communication with the inlet, a first exhaust and a second exhaust in fluid communication with the passage. The first exhaust is arranged to direct a first portion of airflow on the sieve and then up toward the underside of the rotor pan. The second exhaust is located above the rotor pan and arranged to direct a second portion of airflow between the top of the rotor pan and an underside of the concaves.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The current application is related to U.S. patent application Ser. No. 13/326,312 filed on Dec. 14, 2011, entitled “Cascade Pan,” and having Attorney Docket No. A0831 H, which is hereby incorporated by reference in its entirety. 
     
    
     BACKGROUND 
       [0002]    Equipment such as, for example, agricultural machines, may have a fan. The fan may be used to create airflow. The airflow may be used for various purposes such as, for example, cleaning and cooling equipment parts. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0003]    The accompanying drawings, which are incorporated in and constitute a part of this disclosure, illustrate various embodiments of the disclosure. In the drawings: 
           [0004]      FIG. 1  is a diagram of a combine; 
           [0005]      FIG. 2  is a diagram of a dual outlet fan; and 
           [0006]      FIG. 3  is a flowchart showing a method for separating grain from material other than grain. 
       
    
    
     DETAILED DESCRIPTION 
     Overview 
       [0007]    A dual outlet fan may be disclosed. The dual outlet fan may comprise a rotor pan, a sieve, a fan, and a duct having a wall. The rotor pan may be arranged below a rotor and may have an underside. The sieve may be arranged below the rotor pan. The fan may be arranged to blow air into an inlet. The wall may define a passage in fluid communication with the inlet, a first exhaust and a second exhaust. The first exhaust may be arranged to direct a first portion of airflow toward the underside of the sieve. The second exhaust may be arranged to direct a second portion of airflow substantially parallel to the rotor pan. 
         [0008]    Both the foregoing general description and the following detailed description are examples and explanatory only, and should not be considered to restrict the disclosure&#39;s scope, as described and claimed. Further, features and/or variations may be provided in addition to those set forth herein. For example, embodiments of the disclosure may be directed to various feature combinations and sub-combinations described in the detailed description. 
       Example Embodiments 
       [0009]    The following detailed description refers to the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the following description to refer to the same or similar elements. While embodiments of the invention may be described, modifications, adaptations, and other implementations are possible. For example, substitutions, additions, or modifications may be made to the elements illustrated in the drawings, and the methods described herein may be modified by substituting, reordering, or adding stages to the disclosed methods. Accordingly, the following detailed description does not limit the invention. Instead, the proper scope of the invention is defined by the appended claims. 
         [0010]    Fans may be used within agricultural equipment to facilitate separating grain from material other than grain (MOG). Fans may be connected to a duct. The fan may produce an airstream. The airstream may be used to stratify the grain and the MOG. Once stratified, the grain may be sent to a storage bin and the MOG may be discarded. 
         [0011]    While this disclosure describes cascade pans in the context of a combine, embodiments are not limited to an agricultural working environment. In other words, applications where a cascade pan may be desirable include not only agricultural equipment, but also include, for example, industrial, mining, and manufacturing applications. 
         [0012]      FIG. 1  is a diagram of a combine  100 . Combine  100  may comprise a separator housing  102 , an operator&#39;s work station and cab  104 , a grain tank  106 , and an elevator assembly  108 . A swingable unloading auger assembly  110  may pivot to a position extending laterally outward to one side of combine  100  to unload grain tank  106 . Unloading auger assembly  110  may swing inward to a storage position as shown in  FIG. 1  when grain tank  106  is not being unloaded. 
         [0013]    Elevator assembly  108  may have a conveyor  112  mounted in an elevator housing  114 . Conveyor  112  may be trained around rear drive sprockets  116  and a front drum  118 . Hydraulic linear actuators  120  may pivot elevator housing  114  to raise and lower the forward end of elevator housing  114 . 
         [0014]    Crop material may be fed to a feed beater  122  by conveyor  112  in elevator housing  114 . Feed beater  122  may feed crop material to a separating rotor  124 . Separating rotor  124  may comprise a feed section  126 , a threshing section  128 , and a separation section  130 . Feed section  126  may move crop material in a spiral path about a generally horizontal fore and aft axis of rotation to separating rotor  124 , toward threshing section  128 . In threshing section  128 , crop material may pass between a cylinder bar  132  and a concave  134  where grain may be threshed. Threshed grain, that is not separated by concave  134 , may be separated in separation section  130  and may pass through a separation grate  136 . A rotor pan  138  may convey grain and chaff forward and may deposit it on a chaffer  140 . Before reaching chaffer  140 , the grain, chaff, and MOG may pass a cascade pan. MOG may be discharged from separating rotor  124  through a rotor discharge  142 . 
         [0015]    Grain and MOG that may pass through concave  134  and separation grate  136  may fall to rotor pan  138 . Rotor pan  138  may convey grain and chaff forward and may deposit it on chaffer  140 . The grain may be cleaned by chaffer  140  and a sieve  144  and air from a fan assembly  146 . Clean grain may fall into a clean grain auger  148 . The clean grain may be conveyed to grain tank  106  by clean grain auger  150  and an elevator (not shown). Tailings may fall into a returns auger  150  and may be conveyed to separating rotor  124  by returns auger and return elevators (not shown), where they may be threshed a second time. 
         [0016]      FIG. 2  is a schematic of rotor pan  138 &#39;s, sieve  144 &#39;s, and fan assembly  146 &#39;s orientation to on another. Note that while  FIGS. 1 and 2  show only one sieve, embodiments may comprise two or more sieves. Fan assembly  146  may comprise a wall  202 . Wall  202  may define a passage  204 , a first exhaust  206 , and a second exhaust  208 . First exhaust  206  may be arranged below rotor pan  138 . First exhaust  206  also may be arranged to direct a first portion of airflow toward rotor pan  138 , both above and below rotor pan  138  as indicated by first arrows  210 . First exhaust  206  may be arranged at a first elevation and second exhaust  208  may be arranged at a second elevation. The first elevation may be lower than the second elevation. 
         [0017]    The first portion of airflow may be at an angle perpendicular to rotor pan  138 . In addition, the first portion of airflow may be at an angle to assist in discharging MOG from combine  100 . Second exhaust  206  also may be arranged to direct a second portion of airflow toward the rear of combine  100 , as indicated by second arrows  212 . 
         [0018]    During operation, a fan may be located inside passage  204 . The fan may blow air into first exhaust  206  and second exhaust  208 . The amount of air blown into first exhaust  206  and second exhaust  208  (i.e., the first portion of airflow and the second portion of airflow) may be equal or different. In other words, the first portion of airflow and the second portion of airflow may have the same or differing volumetric flow rates. 
         [0019]    During operation, a crop (e.g., corn) may be separated into grain and MOG by concave  134 . The grain and MOG may pass through separation grate  136  and travel to rotor pan  138 . As the grain and MOG falls toward rotor pan  138  the grain and MOG may be stratified by air (i.e., the first portion of airflow as represented by arrows  210 ). As the grain and MOG are separated by the first portion of airflow, the second portion of airflow may blow the MOG below and around rotor discharge  142 . 
         [0020]    The stratification may be caused by density differences between the grain and MOG. For example, corn kernels may have a higher density the stalk or cob. As the air passes toward rotor pan  138 , the denser kernels may fall through the updraft at a faster rate than the stalk or cob. In other words, the first portion of airflow may retard a velocity of material other than grain to a greater extent that the velocity of the grain. Suspending the MOG in the airflow may allow the second portion of airflow to assist in moving the MOG toward the rear of combine  100  for discarding via rotor discharge  142 . 
         [0021]    The fan may be configured to cause the first portion of airflow and the second portion of airflow to pulsate. For example, the fan may be configured to cause the first portion of airflow and the second portion of airflow to pulsate asymmetrically. For instance, the fan may cause a sudden increase in the first portion of airflow&#39;s flow rate followed by a sudden increase in the second portion of airflow&#39;s flow rate. In other words, the fan may be configured to cause alternating pulses of airflow. The fan may also be configured to adjust a flow rate of the airflow. 
         [0022]    In addition, the fan may be configured to cause the first portion of airflow and the second portion of airflow to pulsate symmetrically. For example, the fan may be configured to cause the first portion of airflow and the second portion of airflow to pulsate at approximately the same time. In addition, the first portion of airflow and the second portion of airflow may be uniform. 
         [0023]      FIG. 3  shows a flowchart for a method  300  for separating grain from MOG. Method  300  may begin at stage  305  and proceed to stage  310  where a crop (e.g., corn) may be separated, via a rotor in threshing section  128 , into grain and MOG. From stage  310  where the crop is separated into grain and MOG, method  400  may proceed to stage  315  where the grain and MOG may be stratified. 
         [0024]    As described above, stratification of the grain and MOG may be accomplished by blowing the first portion of air opposite a direction of travel of the grain and the MOG. For instance, the grain and MOG may be traveling in a downward direction and the air may be traveling in an upward direction. 
         [0025]    From stage  315  where the grain and MOG are stratified, method  300  may proceed to stage  320  where the MOG may be discharged from combine  100 . The MOG may be discharged from combine  100  by blowing the second portion of air perpendicular to the first portion of air (i.e., toward rotor discharge  142 . From stage  320  where the MOG is discharged from combine  100 , method  300  may proceed to stage  325  where the grain is received at clean grain auger  148 . Method  400  may then terminal at ending block  330 . 
         [0026]    An embodiment may comprise an apparatus. The apparatus may comprise a rotor pan, a sieve, a fan, and a duct having a wall. The rotor pan may be arranged below a rotor and may have an underside. The sieve may be arranged below the rotor pan. The fan may be arranged to blow air into an inlet. The wall may define a passage in fluid communication with the inlet, a first exhaust and a second exhaust. The first exhaust may be arranged to direct a first portion of airflow toward the underside of the rotor pan. The second exhaust may be arranged to direct a second portion of airflow substantially parallel to the rotor pan, both above and/or below the rotor pan. 
         [0027]    Another embodiment may comprise an apparatus. The apparatus may comprise a combine having a rotor pan, a sieve, a fan, and a duct having a wall. The rotor pan may be arranged below a rotor and may have an underside. The sieve may be arranged below the rotor pan. The fan may be arranged to blow air into an inlet. The wall may define a passage in fluid communication with the inlet, a first exhaust and a second exhaust. The first exhaust may be arranged to direct a first portion of airflow towards the underside of the rotor pan. The second exhaust may be arranged to direct a second portion of airflow substantially parallel to the rotor pan. 
         [0028]    Yet another embodiment may comprise a method. The method may comprise: separating, within a rotor, a crop into grain and material other than grain (MOG); stratifying the grain and MOG as the grain and MOG travel from the rotor to a sieve; and discharging the MOG from a combine. 
         [0029]    Both the foregoing general description and the following detailed description are examples and explanatory only, and should not be considered to restrict the invention&#39;s scope, as described and claimed. Further, features and/or variations may be provided in addition to those set forth herein. For example, embodiments may be directed to various feature combinations and sub-combinations described herein. 
         [0030]    All rights, including copyrights, in the code included herein are vested in and the property of the Applicant. The Applicant retains and reserves all rights in the code included herein, and grants permission to reproduce the material only in connection with reproduction of the granted patent and for no other purpose. 
         [0031]    While the specification includes examples, the invention&#39;s scope is indicated by the following claims. Furthermore, while the specification has been described in language specific to structural features and/or methodological acts, the claims are not limited to the features or acts described above. Rather, the specific features and acts described above are disclosed as example embodiments.