Abstract:
Cotton harvester frame structure includes main structural members elevated to approximately cab floor level and extending horizontally rearwardly in a planar fashion over the engine compartment and the rear axle. The structural members attach to the central portion of the rear axle to provide added clearance for larger wheels and tires. The single elevated plane of the main frame structure provides simplified attachment of a power module including a transversely mounted engine. Access areas under the main structural members are of sufficient minimum width and height to allow an operator or an assembler to stand fairly erect while accessing most areas of the power module and a harvester fan.

Description:
FIELD OF THE INVENTION 
   The present invention relates generally to agricultural harvesters and, more specifically, to a frame for a harvester. 
   BACKGROUND OF THE INVENTION 
   As capacity of agricultural harvesters increases, the added size and weight of the machines require larger tires and wheels. Maintaining an acceptable harvester turn radius, particularly with oscillating steerable rear axles having large capacity wheels, is a continuing source of difficulty. 
   On harvesters such as cotton pickers, the ability to provide either a conventional cotton basket or a special cotton processing system such as a cotton baler would be very advantageous. However, most presently available frame systems fail to easily accommodate such a conversion. Also, providing convenient access to components such as the engine, tanks, cab, and crop handling systems on the large capacity machines is complicated by the size of the required components. Although transversely mounted power systems such as shown in commonly assigned U.S. Pat. Nos. 5,499,491 and 6,901,732 have alleviated some of the problems, clearance at the front and rear of the of the power system support frame is limited and makes access to the sides of the of the engine relatively difficult. 
   SUMMARY OF THE INVENTION 
   It is therefore an object of the present invention to provide an improved harvester frame structure that overcomes most or all of the aforementioned problems. It is another object to provide such frame structure that is particularly useful for a cotton harvester. 
   It is a further object to provide in improved harvester frame structure with wheel structure that accommodates large capacity components and yet has a turning radius comparable to more conventional lower capacity harvesters. It is another object to provide such structure particularly useful with oscillating steerable rear axles. 
   It is still another object to provide a harvester frame structure supporting a transversely mounted engine having increased access to the sides of the engine compared to at least most previously available frame structures. It is a further object to provide such a structure having increased vertical clearance adjacent the engine and providing simplified attachment of a power module including one or more components such as a transversely mounted engine, a hydraulic pump and a cooling system. 
   It is another object to provide a harvester frame structure that establishes a platform for conveniently attaching modular components such as an engine module, tanks, a cab, and crop handling systems. It is still another object to provide such a frame structure that facilitates access to and interchanging or components. 
   Harvester frame structure constructed in accordance with teachings of the present invention includes a front axle similar to existing front axle structures. However, behind the front axle the main structural members are elevated to approximately the floor level of a cab and extend horizontally rearwardly in a planar fashion over the engine compartment and over the rear axle. A rear axle support extends downwardly from the plane of the main frame and attaches to the central portion of the rear axle to provide added clearance for larger wheels and tires by eliminating the chassis width restriction in relation to the steering angle. With the elevated frame and central rear axle connection, the steering angle of a high capacity machine can be maintained or even improved compared to a lower capacity machine with a more conventional frame structure. The frame structure is lengthened, and a power module support depends from the underside of the frame supporting a power module including a transverse engine and driven components. Accommodation spaces are provided behind the front drive wheels and forwardly of the rear steerable wheels. The accommodation spaces extend between the sides and are of sufficient minimum width and height to allow an operator or an assembler to stand fairly erect while accessing most areas of the power module and the, harvester fan. 
   In addition to improving steering angle and providing additional vertical clearance for access areas on either side of a transversely extending engine in the engine compartment, the single elevated plane of the main frame structure provides simplified attachment of a power module including, for example, the transversely mounted engine, a hydraulic pump and a cooling module. Sufficient vertical clearance between ground and the elevated plane of the frame allows an operator convenient access to most all areas adjacent the sides of the engine including the area of a harvester fan. Since the operator can stand fairly erect, work on the power module can be completed faster and more conveniently with less fatigue. 
   The frame structure provides for logical and sequential attachment of components in varying levels of assembly. For a cotton picker, the attachment sequence includes tanks, cab, and cotton handling system. The arrangement of the frame structure allows a conventional basket to be attached in place of the handling system. 
   These and other structures, features and advantages of the present invention will become apparent upon reading the following detailed description in view of the drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a side view of a cotton harvester with parts removed to better show the frame structure. 
       FIG. 2  is an enlarged perspective view of the frame structure for the harvester of  FIG. 1 . 
       FIG. 3  is a view similar to  FIG. 2  but inverted to better show frame underside details. 
       FIG. 4  is a view of a portion of a cotton harvester having a basket mounted at the aft end of the frame structure. 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENT 
   Referring now to  FIG. 1 , therein is shown a harvester  10  having frame structure  12  supported by driven forward ground wheels  16  and rear steerable wheels  18  for forward movement F over the ground. A cab  20  is supported on a forward portion  12   a  of the frame structure  12  forwardly of a front axle support  22  which extends downwardly from the portion  12   a  and supports the drive wheels  16 . A row unit support frame assembly  26  is pivotally connected to the support  22 , and row harvesting units  30  are transversely spaced on the frame assembly  26 . Hydraulic lift cylinders  32  raise and lower the units  30 . 
   The frame structure  12  is generally of tubular and panel construction with parallel sides  12   s . The structure  12  includes a central module support area  12   c  generally centered in the fore-and-aft direction between the wheels  16  and the wheels  18  behind the forward portion  12   a . A central power module support or engine compartment  40  depends from the area  12   c  and includes a forward transversely extending wall  42  offset rearwardly from the wheels  16  and an opposite rear wall  44  offset forwardly from the rear wheels  18 . The power module support  40  provides primary support for main power components or power module  46  on the harvester, such as a transversely mounted engine  46   a , hydraulic pumps  46   b  and a cooling module  46   c  located on the far side of the engine  46   a  as viewed in  FIG. 1 . The components are contained substantially below a plane P generally coinciding with the plane of the main frame structure  12 . 
   As best seen in  FIG. 1 , the module support walls  42  and  44  define upright front and rear accommodation spaces  52  and  54  for access to front and rear portions of the power module support  40 . The accommodation spaces  52  and  54  extend upwardly from the ground to the horizontal plane P and provide convenient operator access to the sides of the engine  46   a  and to other components connected to the support  40 . The spaces  52  and  54  extend substantially continuously between the sides of the frame structure  12  and provide generally uninterrupted access to the sides of the engine and to other power module components under the horizontal plane P. The accommodation spaces  52  and  54  have heights D 2  and D 4 , respectively, comparable to the height of the drive forward drive wheels  16  so that most operators can stand fairly erect as they work adjacent the module support. 
   The frame structure  12  as shown is generally rectangular and extends rearwardly to an aft frame portion  12   d . A rear axle box frame or inverted pedestal  60  is centrally connected to the aft frame portion  12   d , and an oscillatable rear axle assembly  62  is pivotally connected to the box frame  60  and mounts the steerable wheels  18  for oscillation about a central fore-and-aft extending axis  62   a . The uppermost portions of the forward drive wheels  16  and the rear steerable wheels  18  are located closely adjacent but below the plane P. 
   The harvester  10 , shown as a cotton picker with a rear-mounted cotton processor or crop receiver  70  such as a round baler, includes an unloading device  72  pivotally connected to an aft downwardly depending end  12   r  of the frame structure  12  for receiving a cotton bale or module released from the processor and depositing the bale or module on the ground or on a module carrier. The aft extremity of the processor or receiver  70  is generally aligned with the aft extremity of the frame  12 . 
   The aft end of the frame structure  12  includes a downwardly and rearwardly sloped ramp  76 , best seen in  FIG. 2 , and the unloading device  72  is pivotally connected at  72   a  near the lower end of the ramp  76  for movement between a raised transport position (shown) and a lowered release position. The processor or baler  70  as shown includes pivoting clam shell sections  70   a  and  70   b  which open to release  2  bale unto the ramp  76  for movement onto the unloading device  72 . Further details of the general structure can be found in commonly assigned U.S. Pat. Nos. 6,941,740; 6;921,996; 6,901,732 and 6,263,650. However, the length of the frame  12  and the wheelbase of the harvester  10  is increased compared with the previous structures for improved stability and for provision of relatively wide access spaces adjacent the front and rear of the power module. As shown, the accommodation spaces  52  and  54  have an approximate height greater than five feet and on the order of D 2 =D 4 =82 inches (2 meters). The approximate minimum width of accommodation spaces is 17 inches (43 cm), thereby providing excellent accessibility to the power module and other components in the accommodation areas. 
   Rear wheel accommodation spaces  18   a  are defined outwardly adjacent the ramp  76  and below the sides  12   s  of the frame structure  12  to receive the wheels  18  as the axle assembly  62  pivots. The spaces  18   a  receive the wheels  18  without interference, even when the wheels  18  are steered to their maximum turn positions and the axle is in maximum oscillated positions. Axle stops  80  project downwardly and outwardly from the lower portion of the box frame  60  to engage the pivoting axle assembly  62  at the maximum oscillated positions. As the axle assembly  62  oscillates over uneven ground, the wheels  18  remain below the plane P. The underframe wheel design facilitates use of oversized wheels to accommodate high capacity components without sacrificing turn radius. 
   An air duct system  90  extends from the row units  30  through the frame structure  12  to a first cotton receiver  92  supported on the frame structure  12  behind the cab  20  and forwardly of the processor  70 . The receiver  92  provides intermediate storage for cotton received from the air duct system  90  and meters the cotton to the processor  70 . A cotton fan  94  is located near the front of the power module support  40  and provides a source of air to the air duct system  90  to propel cotton material from the row units  30  to the receiver  92 . The fan  94  is easily accessible from the space  52 . An auxiliary gear box  96  driven by the engine  46   a  powers the hydraulic pumps  46   b  and the cotton fan  94 . 
   Water, lubricant and fuel tanks indicated generally at  98  are supported on the frame structure  12  adjacent the receiver  92 . The cab  20 , processor  70 , receiver  92  and tanks are supported above the plane P. The harvester construction provides for logical and sequential attachment of components in varying levels of assembly. For the cotton picker  10 , the attachment sequence includes the tanks  98 , the cab  20 , and cotton handling system including the processor  70  and the first receiver  92 . The accommodation space  52  facilitates access to the fan  96  and fan drive structure. 
   The arrangement of the frame structure  12  allows a conventional cotton basket  100  ( FIG. 4 ) to be attached in place of the cotton handling system shown in  FIG. 1 . With the conventional basket construction, the ramp  76  may be eliminated, and the basket  100  is connected to the frame  12 ′ above the frame sections  12   c  and  12   d ′. The box frame  60 ′ for the oscillating axle assembly  62  is connected adjacent the plane P of the frame structure  12 ′. The air duct system  90  is positioned to direct harvested cotton into the upper forward portion of the basket  100 . The above-described frame structure provides unparalleled access for assembly, inspection and maintenance. 
   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.