Abstract:
A system and method of operation of a draper header of an agricultural work machine during a deslugging or clean out operation and after resumption of normal crop processing. During the deslugging or clean out operation, a feed draper is reversed or paused and the at least one side draper is paused. The method includes automatically resuming operation of the feed draper and at least one side draper in a graduated progression for more efficient clearing of the slug or blockage of crop material.

Description:
This application is the US National Stage for International Application No. PCT/US2012040245, filed on May 31, 2012, which itself is related to and claims the benefit of U.S. Provisional Application No. 61/491,529 filed on May 31, 2011. 
    
    
     TECHNICAL FIELD 
     This invention relates generally to an agricultural harvesting machine and more particularly to a system and method of operation of a draper header during and after a deslugging or clean out operation, including automatically pausing or reversing operation of a feed draper and at least one side draper and automatically resuming operation of the feed draper and the at least one side draper in a graduated progression for more efficient clearing of the slug or blockage of crop material. 
     BACKGROUND ART 
     The disclosure of U.S. Provisional Application No. 61/491,529, filed May 31, 2011, is hereby incorporated herein in its entirety by reference. 
     Agricultural harvesting machines, such as combines, comprise a variety of apparatus and systems for receiving and processing crops. In particular, a combine will include a header operable for severing crops and other plant material from root structure and conveying the severed crop and plant material to a feed mechanism of the combine. The feed mechanism will typically include an enclosed feeder housing containing a feed conveyor, which feed conveyor will typically include parallel chains connected by slats, which chains encircle sprockets which are driven by a feeder drive to move the chains and slats upwardly and rearwardly along a floor of the housing, for inducting and conveying the crop and plant material, as well as debris that may be contained therein, into an inlet region of a threshing system of the combine. The threshing system, in turn, will typically include at least one rotor rotatable within a cavity or space defined at least partially by a concave structure having an array or arrays of openings therein sized for passage of grain therethrough. The rotor will include elements for inducting the crop and other material into the cavity and conveying the material through a crop separation clearance between the outer region of the rotor and the inner region of the concave, for separating grain and other small elements of the crop material from larger elements thereof, typically including leaves, stalks, cobs, husks and the like, depending on the crop being harvested. The separated grain is then expected to pass through the openings of the concave for further processing. 
     From time to time during operation of an agricultural combine, a slug, that is, an incorrectly processed and/or compacted mass of crop material and/or weeds, particularly stringy or viny weeds, debris, or other material, may be inducted into the feed mechanism and/or the threshing mechanism and become lodged or packed or jammed, to possibly block or interrupt throughput of crop material through the combine, and/or damage components of the feed and/or threshing mechanism, thus necessitating removal of the blockage or slug. Thus, when the combine encounters a slug of crop which plugs the draper sickle knife, feed draper, feed auger, feeder house, or threshing rotor, the operator must stop the normal forward feeding of crop and momentarily reverse the feeding mechanisms in an attempt to break up the slug of crop and eventually continue harvesting. 
     Once a slug has developed in the crop processing mechanism which refers to the feed mechanism and the threshing mechanism of the combine, a number of different actions depending on, the combine status, the type, severity and location of the slug, may be necessary to effect removal of the slug. These actions in response to encountering a slug or blockage of crop material may be performed by the operator, selected by the operator from a number of predetermined deslugging routines, or automatically run as a function of sensed parameters representative of the type and location of the slug or blockage. One such system and method is described in Bundy et al., U.S. Pat. No. 7,452,267 issued Nov. 18, 2008 to CNH America LLC which is herein incorporated by reference. 
     Actions in response to a blockage or slug in the crop processing mechanism may only entail backing the slug or blockage away from the mechanism at which it became lodged, sufficiently so as to break it up or better process or compact it for passage through the feed and/or threshing mechanism. A slug or blockage that cannot be sufficiently broken up to pass through the mechanism may be carried off the front of the header by reversing one or both mechanisms to discharge the slug or blockage onto the feed draper and reversing the feed draper to carry the slug or blockage from the front of the header. 
     For a slug or blockage in the threshing mechanism, it may be sufficient to repeatedly jog the rotor through small angular movements, until the resulting low impulsive loads break down the slug and free it. In a more extreme example, it may be necessary to rock the rotor more violently back and forth in an agitating motion, at different amplitudes and different frequencies, occasionally with an asymmetric motion and relatively large impulsive loads, for extended periods of time, to incrementally dislodge or work the slug free. In an even more extreme example, manual intervention may be required, to open up the feed mechanism and/or the threshing mechanism, and manually clear the slug piece by piece. 
     Once the slug or blockage has been cleared, normal crop processing resumes and the draper header again conveys crop material to the feed mechanism. The distribution of the crop material on the feed and side drapers at this point depends on their operation during the deslugging operation. For example, if the feed and side drapers continue in their normal operating direction during the deslugging process, the side belts continue to add more crop material to the center belt which is counterproductive to the unplugging process. In other words, crop material distributed along the side drapers when the combine stopped harvesting is fed onto the feed draper and toward the inlet of the feeder housing. When normal operation resumes, all of the crop material that was distributed along the draper header simultaneously enters the feed mechanism, potentially leading to another blockage. As another example, if reverse operation of the feed and side drapers is disabled during the deslugging operation, the operator will not have the option of discharging a slug from the front of the header. Another option is to reverse both the feed and the side drapers during the deslugging operation. Reference in this regard, Enns et al., U.S. Pat. No. 7,497,069 issued on Mar. 3, 2009 to MacDon Industries Ltd., which describes a hydraulic circuit that reverses both the feed and side drapers during reverse operation of the feed and/or threshing mechanism. Reversing the feed draper, when not clearing a slug or blockage from the front of the header, results in unnecessary loss of the crop material on the feed draper when harvesting stopped. In addition, reversing the side drapers results in accumulation of the crop material on the side drapers at the outer ends thereof that will later be fed into the feed mechanism potentially leading to another blockage. 
     Accordingly, what is sought is a system and method for operating a draper header during and subsequent to a slug clean out operation, which provides one or more of the capabilities and overcomes at least one of the problems, shortcomings or disadvantages as set forth above. 
     SUMMARY OF THE INVENTION 
     What is disclosed is a system and method for operating a draper header during and subsequent to a slug clean out operation, which provides one or more of the capabilities and overcomes at least one of the problems, shortcomings or disadvantages as set forth above. 
     A draper header of an agricultural harvesting includes a feed draper configured and operable for conveying crop material thereon in a feed direction toward a crop processing mechanism of the harvesting machine and a reverse direction away from the crop processing mechanism. The header also includes at least one side draper configured and operable for conveying crop material thereon in a sideward direction to the feed draper. The crop processing mechanism includes a feed mechanism and a threshing mechanism, and operation of the crop processing mechanism in a deslugging or clean out process includes operating the crop processing mechanism in a reverse direction and a feed direction for movement of crop material in a reverse direction and a feed direction, respectively. 
     According to a preferred embodiment of the invention, in response to operation of the crop processing mechanism in the reverse direction, the operation the feed draper and the at least one side draper in the feed direction is automatically paused. After the deslugging or clean out operation, the crop processing mechanism is operated in the feed direction. In response to operation of the crop processing mechanism in the feed direction for a first predetermined period of time, operation of the feed draper is automatically resumed in the feed direction for conveying crop material in the feed direction. In response to operation of the crop processing mechanism in the feed direction for a second predetermined period of time, longer than the first predetermined period of time, operation of the at least one side draper is automatically resumed in the feed direction for conveying crop material in the feed direction toward the feed draper. In addition, in response to operation of the crop processing mechanism in the reverse direction for a third predetermined period of time, the feed draper is automatically operated in the reverse direction to convey crop material thereon in the reverse direction. 
     According to a preferred feature of the invention, when the crop processing mechanism is operated in the reverse direction, the feed draper remains paused until the crop processing mechanism is operated in the feed direction for the first predetermined period of time, indicating the deslugging operation broke apart or compacted the slug sufficiently for normal crop processing to resume. In this case, the feed draper resumes operation in the feed direction, and after the second predetermined period of time the at least one side draper resumes operation in the feed direction. Alternately, the feed draper remains paused until the crop processing mechanism is operated in the reverse direction for the third predetermined period of time, indicating the slug has been discharged onto the feed draper and should be conveyed from a forward end of the header. In this case, the feed draper resumes operation in the reverse direction until the slug of crop material is discharged from the forward end of the header. 
     According to a preferred aspect of the invention, the first predetermined period of time is sufficient to allow the crop processing mechanism to process at least a portion of the crop material therein. 
     According to another preferred aspect of the invention, the second predetermined period of time is sufficient to allow the feed draper to convey at least a portion of crop material thereon to the feed mechanism. 
     According to another preferred feature of the invention, at least one slug clean out operation includes operation of the crop processing mechanism in alternating reverse and feed directions for variable durations. Accordingly, the first predetermined period of time is longer than the variable durations of operation in the feed direction, and the third predetermined period of time is longer than the variable durations of operation in the reverse direction of the at least one slug clean out operation. This will prevent the header from misinterpreting the repeated reversals of direction of the crop processing mechanism during the slug clean out operation. 
     According to yet another preferred feature of the invention, the variable durations of operation of the crop processing mechanism in the feed direction and the reverse direction are predetermined. 
     According to yet another preferred feature of the invention, the variable durations of operation of the crop processing mechanism in the feed direction and the reverse direction are selected by an operator. 
     According to yet another preferred feature of the invention, the variable durations of operation of the crop processing mechanism in the feed direction and the reverse direction are automatically determined by parameters of the at least one slug clean out operation. 
     According to yet another preferred aspect of the invention, the header further includes an auger disposed near a rear end of the feed draper, and operation of the auger is resumed after the second predetermined period of time. 
     According to yet another preferred aspect of the invention, operation in the feed direction conveys the cut crop material sidewardly on the at least one side draper to the feed draper, along the feed draper to a feed conveyor within a feeder housing of the feed mechanism, through feed mechanism to the threshing mechanism including a rotor and concave, through the threshing mechanism for further cleaning and processing in the agricultural harvesting machine. 
     Preferred embodiments of the system of the invention comprise hydraulic embodiments and electromechanical embodiments. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side view of an agricultural combine including a crop processing mechanism, which includes a feed mechanism and a threshing mechanism and a draper header including a feed draper and side drapers for use with the system and method of the invention; 
         FIG. 2  is a simplified end view of a rotor and a concave of the threshing mechanism of the combine of  FIG. 1 , illustrating the crop separation clearance between the rotor and the concave; 
         FIG. 3  is a simplified top view of the header, the feed mechanism, and a portion of the threshing mechanism of the combine of  FIG. 1 , illustrating a slug or blockage of crop material in the feed mechanism; 
         FIG. 4  is a simplified top view of the header, the feed mechanism, and a portion of the threshing mechanism of the combine of  FIG. 1 , illustrating operation of the feed draper in the reverse direction in response to operation of the feed mechanism in the reverse direction for the third predetermined period of time representative of a clean out operation in which the slug of crop material discharged onto the feed draper is conveyed from the forward end of the header; 
         FIG. 5  is a simplified top view of the header, the feed mechanism, and a portion of the threshing mechanism of the combine of  FIG. 1 , illustrating the operation of the feed mechanism in the feed direction during the first predetermined period of time after a clean out operation; 
         FIG. 6  is a simplified top view of the header, the feed mechanism, and a portion of the threshing mechanism of the combine of  FIG. 1 , illustrating the operation of the feed mechanism in the feed direction after the first predetermined period of time and during the second predetermined period of time after the clean out operation; 
         FIG. 7  is a simplified top view of the header, the feed mechanism, and a portion of the threshing mechanism of the combine of  FIG. 1 , illustrating the operation of the feed mechanism in the feed direction after the second predetermined period of time after the clean out operation; 
         FIG. 8  is a top level flow diagram including the method of operation of the draper header during and after the clean out operation; 
         FIG. 9  is a simplified hydraulic circuit showing hydraulic fluid flow in the forward direction indicating the crop processing mechanism is operating in the feed direction; 
         FIG. 10  is a simplified hydraulic circuit showing the operation of the fluid pumps in the reverse direction in response to operation of the crop processing mechanism in the reverse direction indicative of the slug clean out operation; 
         FIG. 11  is a simplified hydraulic circuit showing operation of the hydraulic pumps in the reverse direction in response to operation of the crop processing mechanism in the reverse direction after the third predetermined period of time indicative of discharging the slug of crop material from the forward end of the header; 
         FIG. 12  is a simplified hydraulic circuit showing operation of the fluid pumps in the forward direction during the first predetermined period of time wherein fluid flow remains diverted from the feed draper and side drapers following a slug clean out operation; 
         FIG. 13  is a simplified hydraulic circuit showing operation of the fluid pumps in the forward direction after the first predetermined period of time wherein operation of the feed draper in the feed direction is resumed following the slug clean out operation; and 
         FIG. 14  is a simplified hydraulic circuit showing operation of the fluid pumps in the forward direction after the second predetermined period of time wherein operation of the side drapers in the feed direction is resumed following a slug clean out operation. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings, wherein  FIG. 1  depicts a representative agricultural harvesting machine, shown here as a combine  20 , having a draper header  22  and a crop processing mechanism  27 , including a feed mechanism  28  and a threshing mechanism  30 . Although illustrated with a draper type header, the present invention is suitable for a header using alternate conveyance systems, such as, but not limited to, an auger. In addition, the present invention is suitable for use with a windrowing type machine wherein the severed crop material is discharged from the rear of the machine. 
     Referring also to  FIG. 3 , draper header  22  is mounted on a forward end  36  of feed mechanism  28 , and is operable for cutting or severing plant material or crops such as, but not limited to, small grains such as wheat and soybeans, and conveying the severed crop material toward an inlet opening of feed mechanism  28  for conveyance into combine  20  for threshing and cleaning, in the well known manner, as combine  20  moves forwardly over a field. Draper header  22  includes a feed draper  24  configured and operable for conveying crop material thereon in a feed direction, denoted by arrow F, toward feed mechanism  28 , and a reverse direction, denoted by arrow R, away from feed mechanism  28  or toward a forward end  34  of header  22 , and at least one side draper  26  configured and operable for conveying crop material thereon in a sideward feed direction denoted by arrows C and D to feed draper  24 . 
     Feed mechanism  28  is mounted on a front end  32  of combine  20  generally beneath an operator cab  33 . Feed mechanism  28  includes a feeder housing  38  containing a feed conveyor  40  operable for conveying the crop material upwardly and rearwardly through housing  38  into an inlet region of threshing mechanism  30 . Feed conveyor  40  generally includes at least two endless chains  42  encircling drive sprockets  44  located in a rear end of feeder housing  38  and a drum  45  located in forward end  36  of feed mechanism  28 . A plurality of slats (not shown) extends between chains  42  and facilitates the conveying of crop and other material through feeder housing  38 , in the well-known manner. In this latter regard, during normal crop processing, drive sprockets  44  will be rotated in a counterclockwise direction for moving chains  42  and the slats upwardly and rearwardly within feeder housing  38  for conveying crop and other plant material upwardly and rearwardly toward threshing mechanism  30  in feed direction F. Alternately, when reversed, drive sprockets  44  will be rotated in a clockwise direction for moving chains  42  and slats downwardly and forwardly within feeder housing  38  for conveying crop and other plant material away from threshing mechanism  30  in reverse direction R. 
     Referring also to  FIG. 2 , threshing system  30  includes a rotatable, generally cylindrical rotor  46  including a tapered forward end having at least two vanes or flights  47  ( FIG. 1 ) extending radially outwardly therefrom. At least a lower region of rotor  46  rearwardly of flights  47  is surrounded by a concave  48  located in radially outwardly spaced relation thereto, defining a crop separation clearance  50  extending circumferentially at least partially around the outer cylindrical surface of rotor  46 . Referring more particularly to  FIG. 2 , concave  48  is supported beneath rotor  46  by a support structure including a pivotal connection  54  on one side, and one or more hanger straps  56  on the other side. Hanger strap  56  is connected to a free end of an adjusting arm  58  supported and controllably movable upwardly and downwardly by an actuator  60 , which can be, for instance, a fluid cylinder. Actuator  60  is of well-known, conventional construction, and can be controlled by an operator using a control (not shown) in the well-known manner to precisely position concave  48  within a range of relatively more closely spaced positions in relation to rotor  46  (represented in solid lines) to provide a crop separation clearance suitable to for desired threshing characteristics for the crop to be harvested. The position of concave  48  can be sensed or determined in the conventional, well known manner using a concave position sensor  61 , which can be associated with or incorporated into actuator  60 , or located elsewhere for sensing information representative of the position of concave  48  relative to rotor  46 . This position and/or the crop separation clearance may be indicative of the presence of a slug or blockage of crop material. Actuator  60  can also be controlled in the same manner to position concave  48  in at least one more lowered position (represented in dotted lines) wherein the crop separation clearance is opened so as to be suitable for facilitating slug clean out operations in threshing mechanism  30 . 
     As combine  20  is moved forwardly through a field for normal crop processing, crops and other plants severed by header  22  will be conveyed to feed mechanism  28 , and through feed mechanism  28  to threshing mechanism  30 , wherein a mat of the crop and other plant material will move in a generally helical path through crop separation clearance  50 , as effected by rotation of rotor  46 . Grain and other small elements of plant material will then pass through arrays of openings or spaces in concave  48 , so as to fall therefrom onto a cleaning system (not shown) of combine  20 , which will further clean the grain from the other small elements of plant material. From the cleaning system, the clean grain will be conveyed into a clean grain tank  62 , in the well-known conventional manner. Larger elements of plant material, such as straw, leaves, stalks, cobs, and the like, which do not pass through the openings of concave  48  are conveyed through crop separation clearance  50  past the rear end of rotor  46  and concave  48 , and are disposed of through the rear end of combine  20 , also in the well-known manner. 
     Referring also to  FIGS. 3 through 8 , when an operator and/or a slug detection system detects a slug  70  or blockage of crop material in feed mechanism  28  and/or threshing mechanism  30 , combine  20  stops normal crop processing for a slug clean out operation for eliminating slug  70  or the blockage of crop material. Slug clean out operations typically initiate by operating crop processing mechanism  27  in reverse and may alternately switch the operation of crop processing mechanism  27  between reverse and feed directions to free slug  70  as illustrated by arrow  75  in feed mechanism  28  and arrow  77  at rotor  46  in  FIG. 4 . 
     According to the present invention, in response to operation of the crop processing mechanism in the reverse direction, operation of feed draper  22  and the at least one side draper  26  in the feed direction is automatically paused as seen in blocks  74 ,  76 , and  78  of  FIG. 8 . Initially pausing feed draper  24  is advantageous because operation in the feed direction conveys additional cut crop material into feed mechanism  28  and/or threshing mechanism  30  interfering with the slug clean out operation, and operation in the reverse direction unnecessarily carries cut crop material off forward end  34  of header  22 . Pausing the at least one side draper  26  during the clean out operation is advantageous because operation in the feed direction adds additional cut crop material to feed draper  24 , and operation in the reverse direction causes cut crop material thereon to build up at the outer ends of the at least one side draper  26 . So, operation of the at least one side draper  26  in either direction creates an uneven distribution of crop material and the possibility of creating a large slug of crop material that may form a new blockage when normal crop processing resumes. 
     After the deslugging or clean out operation, crop processing mechanism  27  is operated in the feed direction. In response to operation of crop processing mechanism  27  in the feed direction for a first predetermined period of time, operation of feed draper  24  is automatically resumed in the feed direction for conveying crop material in the feed direction as seen at blocks  80 ,  82  and  84  of  FIG. 8  and  FIGS. 5 and 6 . In response to operation of crop processing mechanism  27  in the feed direction for a second predetermined period of time, longer than the first predetermined period of time, operation of the at least one side draper  26  is automatically resumed in the feed direction for conveying crop material in the feed direction toward feed draper  24  as seen in blocks  86  and  88  of  FIG. 8  and  FIGS. 6 and 7 . In addition, in response to operation of crop processing mechanism  27  in the reverse direction for a third predetermined period of time, feed draper  24  is automatically operated in the reverse direction to convey crop material thereon, including slug  70  in the reverse direction as seen in blocks  90  and  92  of  FIG. 8  and  FIG. 4 . 
     According to a preferred feature of the invention, when crop processing mechanism  27  is operated in the reverse direction, feed draper remains  24  paused until crop processing mechanism  27  is operated in the feed direction for the first predetermined period of time, indicating the slug clean out operation broke apart or compacted the slug sufficiently for normal crop processing to resume. In this case, feed draper  24  resumes operation in feed direction F, and, after the second predetermined period of time, the at least one side draper  26  resumes operation in feed direction C and D. 
     Alternately, in at least one slug clean out operation, feed draper  24  remains paused until crop processing mechanism  27  is operated in reverse direction R for the third predetermined period of time sufficient for depositing slug  70  onto feed draper  24  as illustrated in  FIG. 4 . In response to this case, feed draper  24  resumes operation in reverse direction R until slug  70  is discharged from the front or forward end  34  of header  22 . 
     According to a preferred aspect of the invention, the first predetermined period of time is sufficient to allow crop processing mechanism  27  to process at least a portion of the crop material therein. This aspect is advantageous because when normal crop processing stops, feed draper  24  has cut crop material thereon en route to feed mechanism  28 . If feed draper  24  remains paused during the slug clean out process, the cut crop material remains on feed draper  24  when it resumes operation in feed direction F. The first predetermined period of time allows crop processing mechanism  27  to process any crop material therein including the crop material that was previously part of slug  70  prior to introduction of the cut crop material on feed draper  24 . 
     According to another preferred aspect of the invention, the second predetermined period of time is sufficient to allow feed draper  24  to convey at least a portion of crop material thereon to feed mechanism  28 . This aspect is also advantageous because when normal crop processing stops, the at least one side draper  26  has cut crop material thereon en route to feed draper  24  that remains thereon when operation of the at least one side draper resumes. The second predetermined period of time allows crop processing mechanism  27  to process any crop material therein and any crop material conveyed from feed draper  24  including the crop material that was previously part of slug  70  prior to introduction of the cut crop material on the at least one side draper  26 . 
     Referring also to  FIGS. 4 through 7 , according to a preferred feature of the invention, at least one slug clean out operation includes operation of crop processing mechanism  27  in alternating reverse and feed directions for variable durations represented by arrows  75  and  77  in  FIG. 4 . Accordingly, the first predetermined period of time is longer than the variable durations of operation of crop processing mechanism  27  in the feed direction F, and the third predetermined period of time is longer than the variable durations of operation of crop processing mechanism  27  in the reverse direction R during the at least one slug clean out operation. This will prevent the header from misinterpreting the repeated reversals of direction of crop processing mechanism  27  during the slug clean out operation as indications that the slug clean out operation is complete or the slug has been discharged onto feed draper  24 . 
     According to yet another preferred feature of the invention, the variable durations of operation of crop processing mechanism  27  in feed direction F and reverse direction R are predetermined. 
     According to yet another preferred feature of the invention, the variable durations of operation of crop processing mechanism  27  in feed direction F and reverse direction R are selected by an operator. 
     According to yet another preferred feature of the invention, the variable durations of operation of crop processing mechanism  27  in feed direction F and reverse direction R are automatically determined by parameters of the at least one slug clean out operation. 
     According to yet another preferred aspect of the invention, the header further includes an auger  66  ( FIG. 3 ) disposed near a rear end of the feed draper, and operation of auger  66  is paused with the at least one side draper  26  and resumed after the second predetermined period of time. 
     Referring now also to  FIGS. 9 through 14 , for a representative hydraulic implementation of one of the preferred embodiments of the system of the invention. During normal crop processing, illustrated by  FIG. 9 , hydraulic fluid flows according to the arrows from fluid pumps  110  and  112 , to a knife drive motor  114 , a feed draper motor  116 , side draper motors  118  and  120 , and an auger motor  122 , and then returns through a filter  124  and a cooler  126 . 
     Referring also to  FIG. 10 , if crop processing mechanism  27 , including feed mechanism  28  and/or threshing mechanism  30 , are operated in reverse to clean out slug  70 , fluid flow is reversed in pumps  110  and  112 . Filter  124  and cooler  126  are isolated from the reverse hydraulic fluid flow with various check valves, including check valves CV 1  and CV 2 . When fluid flow is reversed, as shown by the arrows in  FIG. 10 , an accumulator  128  is charged with hydraulic fluid from pump  110  using backpressure created by an orifice  130 . As long as there is sufficient pressure in accumulator  128 , a feed draper valve  132  and a side draper valve  134  remain energized. When energized, feed draper valve  132  diverts hydraulic fluid away from feed draper motor  118 , and side draper valve  132  diverts oil away from side draper motors  118  and  120  and auger motor  122 . Knife drive motor  114  is always active during forward and reverse hydraulic fluid flow, which is desirable. 
     Referring also to  FIG. 11 , when crop processing mechanism  27  is operated in the reverse direction for the third predetermined period of time, valve  136  is selected to allows operation of feed draper  24  in reverse direction R. Valve  136  isolates accumulator  128  from the path of feed draper motor  116 , regardless of the pressure in accumulator  128 . Valve  134  remains in the fluid path with side drapers  26  and auger  66  to isolate them from the reverse fluid flow so they remained paused as shown in  FIG. 11 . Valve  136  may also be selected by the operator to determine if feed draper  24  operates during the slug clean out mode. 
     Referring also to  FIGS. 12 through 14 , when crop processing mechanism is operated in feed direction F for the first predetermined period of time, fluid pumps are operated in the forward direction. The fluid pressure stored in accumulator  128  and held by check valve CV 3 , but immediately begins to bleed down through orifice  138 . As seen in  FIG. 13 , once the pressure in accumulator  128  reaches a spring rating of feed draper valve  132 , it returns to its neutral position, and feed draper motor  116  resumes operation in the feed direction. Similarly, as seen in  FIG. 14 , once the pressure in accumulator  128  reaches a spring rating of side draper valve  134 , it returns to its neutral position, and side draper motors  118  and  120  and auger motor  112  resume operation. The spring rating in feed draper valve  132  is set higher than that of side draper valve  134  so that the feed draper  24  will engage before the at least one side draper  26 . The spring ratings in valves  132  and  134  correspond to delays that may be incorporated into the first predetermined period of time and the second predetermined period of time, respectively. For example, the time required for the fluid pressure in accumulator  128  to reach the spring rating of feed draper valve  132  may be added to the first predetermined period of time, and the time required for the fluid pressure in accumulator  128  to reduce further to reach the spring rating of side draper valve  134  may be added to the second predetermined period of time. Again, these delays allow crop material in crop processing mechanism  27  to process prior to conveyance of additional crop material from feed draper  24  and/or the at least one side draper  26 . 
     Preferred embodiments of the system of the invention comprise not only hydraulic embodiments but also electromechanical embodiments. 
     In light of all the foregoing, it should thus be apparent to those skilled in the art that there has been shown and described a system and method for operation of a draper header during and after a slug clean out operation. However, it should also be apparent that, within the principles and scope of the invention, many changes are possible and contemplated, including in the details, materials, and arrangements of parts which have been described and illustrated to explain the nature of the invention. Thus, while the foregoing description and discussion addresses certain preferred embodiments or elements of the invention, it should further be understood that concepts of the invention, as based upon the foregoing description and discussion, may be readily incorporated into or employed in other embodiments and constructions without departing from the scope of the invention. Accordingly, the following claims are intended to protect the invention broadly as well as in the specific form shown, and all changes, modifications, variations, and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is limited only by the claims which follow.