Lateral float mechanism for combines
BACKGROUND OF THE INVENTION 
     The present invention relates generally to crop harvesting machines, commonly referred to as combines, and, more particularly to providing a mechanism for allowing the header to laterally float in response to the contour of the ground. 
     Combines, particularly the self-propelled type, are equipped to utilize a variety of crop gathering headers, including headers specifically designed for harvesting corn, cereal grains or soy beans. Normally, these headers are attached to the forward end of the feeder house, which is a structure used to convey crop material from the header to the combine base unit for further harvesting treatment. As is shown in U.S. Pat. No. Re. 26,512, the forward end of the feeder house can be constructed so that the header can be quickly and easily attached thereto. Usually, the feeder house structure is rectangular in shape and includes a rectangular crop inlet opening at the forward end. 
     Particularly with the modern trend of developing headers of increasingly larger sizes, providing the capability of a header to follow the contours of the ground is increasingly desirable. One type of prior art leveling mechanism, as can be seen in U.S. Pat. No. 3,981,125, involves the twisting of the feeder house structure about the centerline thereof (i.e. the line of travel of the combine) to effect an associated lateral floating movement of the header. Hillside combines have been developed to allow the header to follow slopes of up to 45 percent. Such hillside combines have been known to utilize a side pivot mechanism as seen in U.S. Pat. No. 3,731,470, and also a center mounted pivot connection directly between the header and the feeder house wherein the connection involves a specific semi-circular opening between the feeder house and the header. 
     Problems that have been encountered with these prior are lateral float mechanisms include a difficult sealing situation between the feeder house and the base unit as the feeder house is twisted relative to the base unit, and the twisting of the feeder house drive mechanism also increases wear which reduces life in the drive chains. Another problem found in the prior art leveling mechanisms is the matching of different types of headers to different feeder house structures. This problem is particularly relevant to feeder houses having specially shaped crop inlet openings. 
     SUMMARY OF THE INVENTION 
     It is an object of this invention to overcome the aforementioned disadvantages of prior art by providing a pivotal cradle assembly interconnecting the feeder house and the header. 
     It is a feature of this invention to provide a simple means for allowing the combine header to float laterally and follow the contours of the ground. 
     It is another object of this invention to provide a means to give greater flexibility in adapting different detachable headers to different feeder houses. 
     It is still another object of this invention to reduce sealing problems between the feeder house and the combine base unit. 
     It is an advantage of this invention to increase the life of a feeder house driven by reducing the amount of twisting necessary in the feeder house to provide a lateral float capability. 
     It is a further object of this invention to provide a combine header lateral float mechanism which is durable in construction, inexpensive in manufacture, facile in assemblage and simple and effective in use. 
     These and other objects, features and advantages are accomplished according to the instant invention by providing a lateral float mechanism for a combine header wherein the header is detachably mounted to a separate cradle assembly which is centrally pivotably mounted on the feeder house, structure being provided for locking the header to the cradle assembly for preventing fore-and-aft movement between the cradle assembly and the feeder house and for selectively controlling the extent of pivotal movement of the cradle assembly. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The advantages of this invention will become apparent upon consideration of the following detailed disclosure of the invention, especially when taken in conjunction with the accompanying drawings wherein: 
     FIG. 1 is a front elevational view of a self-propelled combine, having a grain header attached thereto, incorporating the principles of the present invention; 
     FIG. 2 is a cross sectional view of the forward portion of the combine, including the header and feader house areas; shown in FIG. 1 taken along line 2--2; 
     FIG. 3 is an enlarged front elevational view of the cradle assembly at the forward end of the feeder house, the header being removed for clarity; 
     FIG. 4 is a side elevational view of the forward portion of the feeder house showing the front face member and the cradle assembly, the detachable header being shown in phantom proximate to the cradle assembly; 
     FIG. 5 is a cross sectional view of the cradle assembly pivot means taken along line 5--5 in FIG. 3; and 
     FIG. 6 is a cross sectional view showing the retaining means interconnecting the cradle assembly and a feeder house taken along line 6--6 in FIG. 3. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the drawings and particularly to FIG. 1, a front elevational view of the crop harvesting machine commonly referred to as a self-propelled combine can be seen. Left and right references are used as a matter of convenience and are determined by standing at the rear of the machine facing the forward end, the direction of travel. This combine 10 is generally comprised of a base unit 12, including a crop harvesting means 13 for separating the desired crop material from the waste crop material, a detachable crop gathering header 20 located forwardly of the base unit 12, a cab 14 elevated above the header 20 for full view of the crop harvesting process occurring therein, a wheeled frame 16 and a feeder house 30 for conveying crop material harvested by the header 20 rearwardly to the base unit 12 for treatment by the crop harvesting means 13, which, for example, can be a conventional threshing unit or the more recently developed rotary type axial flow harvesting unit, as is depicted in the drawings. 
     Referring now to the cross sectional view of FIG. 2, a more detailed view of the general inner workings between the header 20, feeder house 30 and base unit 12 can be seen. The header 20 includes a forwardly disposed crop cutting means 22, seen in FIG. 2 in the form of a reciprocating type mower, for severing crop material from the ground. A reel 24 is disposed above and forwardly of the cutter means 22 to sweep crop material over the cutting means 22 and transport it rearwardly to the consolidating means 26, seen in the form of a consolidating auger 27. The consolidating auger 27 converges crop material towards a centrally disposed crop discharge opening 25, better seen in FIG. 1, for discharge to the feeder house structure 30. 
     As will be discussed hereinafter, varying the angle of the cutting means 22 relative to the ground, as can be seen in phantom in FIG. 2, is important to the efficiency to the crop gathering header, relative to loss of crop material in different types of crops. The frame 28 of header 20 includes a transversely disposed main header beam 29, which is used to support the header 20 from the feeder house 30. One skilled in the art will readily realize that this invention is not limited to a cutting means 22 of the reciprocating type nor a consolidating means 26 in the form of a consolidating auger 27. 
     As can also be seen in FIG. 2, the feeder house 30 generally includes a forwardly disposed, elongated body portion 32 defined by a rearward end 33 pivotably attached to the base unit 12 and a forward end 34 adjacent the header 20 for connection thereto. The body portion 32 includes a passageway 36 therethrough, terminating in a crop inlet opening 39 at the forward end 34, for allowing crop material to be transported rearwardly from the forward end 34 to the rearward end 33. A crop conveying means 40, normally in the form of an endless chain and slat apron conveyor 41, is positioned within the passageway 36 for transporting the crop material rearwardly. Generally, the apron conveyor 41 is driven by a drive shaft 43 positioned at the rearward end 33. A driven shaft 44 adjacent the forward end 34 enables the endless apron conveyor 41 to rotate into an operative position for transporting crop material rearwardly. 
     A crop conveyor drive means 38, which receives rotational power from the header drive shaft 21, is also found mounted on the feeder house 30. The height of the header 20 relative to the ground is controlled by a header lift means 48 interconnecting the feeder house 30 and the base unit 12. By extending the header lift means 48 and pivoting the rearward end 33 of the feeder house 30 about the drive shaft 43, thereby rotating the feeder house 30 about the drive shaft 43, the header 20 can be lifted from the ground without significantly changing the discharge point of the apron conveyor 41 relative to the base unit 12. 
     Referring now to FIG. 4, an enlarged view of the forward end 34, showing the front face member 50 and a detached header 20 in phantom proximate thereto, can be seen. The front face member 50 is a separate structure pivotably attached to the forward end 34 of the feeder house 30 for rotational movement such that the top 51 of the front face member 50 is movable in a fore-and-aft direction. The front face member 50 includes an offset section 53 substantially registerable with the main header beam 29 for supporting the header 20 in a detachable operable position. 
     Although it is possible to attach the front face member 50 to the feeder house 30 without having a fixed pivot point, it has been found to be preferable to use the axis defined by the driven shaft 44 of the conveying means 40 as a fixed pivot point. By such an arrangement, since the distance between the discharge opening 25 and the conveying means 40 is fixed, the efficiency of the crop conveying means 40 to engage the crop material discharged by the header and to convey it rearwardly is not impaired by rotation of the front face member 50. 
     The front face member 50 includes side sheets 57 which project rearwardly in close proximity to the sidewalls 37 of the feeder house 30. The side sheets 57 include a plurality of multi-positionable apertures 58, which can also be in the form of slot-shaped apertures 59. These apertures 58, 59 are registerable with holes (not shown) in the sidewalls 37. Bolts 56, interfitting corresponding apertures and holes serve to restrict and control the extent of movement of the front face member 50 and to act as a stabilizing means 55. 
     The lateral float mechanism 60 can be best seen in FIGS. 3 and 4. A separate cradle assembly 70 is pivotably affixed to the forward end 34 of the feeder house 30 for rotation generally about the direction of travel. In the preferred embodiment seen in FIGS. 3 and 4, the cradle assembly 70 is pivotably affixed to the center of the offset section 53 in the front face member 50 by a pivot means 80; however, the cradle assembly 70 could instead be attached to the forward end 34 of the feeder house 30. For purposes of description, the cradle assembly 70 will hereinafter be referred to as being pivotably affixed to an attachment face 35, which is defined as being that part of the feeder house 30 to which the feeder 20 is attached. 
     The cradle assembly 70 includes a crop passage opening 78 which is registerable with both the header discharge opening 25 and the crop inlet opening 39. The cradle assembly 70 also includes a nesting portion 72 which overlaps the offset section 53 of the attachment face 35 for receiving and attaching the main header beam 29. The nesting portion 72 has a preferred substantially U-shaped configuration, as best seen in FIG. 4, with the forward leg 73 being shorter than the rear leg 74 and bent forwardly for facilitating the connection between the main header beam 29 and the nesting portion 72. To either side of the pivot 80, the nesting portion 72 includes a locking means 75 in the form of a spring loaded locking pin 76 which is positioned to interfit within corresponding holes 77 in the main header beam 29 to lock the beam 29 into an operative position, wherein the crop discharge opening 25, the crop passage opening 78 and the crop inlet opening 39 are substantially aligned. 
     To control the pivotal movement of the cradle assembly 70 about the pivot 80, a pivot control means 90, seen in the form of a screw device 92 to each side of the pivot 80, operates to limit the rotation of the nesting postion 72. The bolts 93, forming part of the screw device 92, are threaded into the offset section 53 of the attachment face 35 and can be adjusted upwardly to restrict the extent of possible rotation of the cradle assembly 70. Moreoever, by proper manipulation of the left and right bolts 93 in conjunction with each other, the cradle assembly 70 can be locked into an infinite number of rotated positions within the confines imposed by the physical constraints of the screw device 92 itself. If should be further realized by one skilled in the art that one or more hydraulic cylinders interconnecting either the base unit or the feeder house and the cradle assembly would be effective as a pivot control means. To further limit the pivotal movement of the cradle assembly 70 and to provide support for the nesting portion 72 upon full left or full right rotation, the offset section 53 of the attachment face 35 includes an inclined ramp 54 on each side of the pivot means 80. 
     A latch mechanism 62 locks the lower end 79 of the cradle assembly 70 to the corresponding portion of the header 20 to further aid in retaining the header 20 in an operative position relative to the cradle assembly 70 and the feeder house 30. Latch mechanism 62 is shown in the preferred embodiment as being of the overcenter variety. The cradle assembly 70 also includes a forwardly projecting crop retention hood 64, which extends into the discharge opening 25 of the header 20 to retain crop material within the feeder house passageway 36. 
     The pivot 80 is best seen in the enlarged view of FIG. 5. A tubular housing 82 is rigidly affixed to the attachment face 35. A circular dowel 84 rotatably extends through the housing 82 and includes a front plate member 86. As is seen in FIG. 3 and FIG. 5, front plate 86 is detachably affixed to the cradle assembly by two screws 88 to facilitate the removal and/or repair of the pivot 80. A rear plate member 87 is rigidly affixed to the rear leg 74 of the nesting portion 72 and is supported by the dowel 84. FIG. 5 reveals the provision of a grease zerk 89 for renewing the supply of lubricant between the dowel 84 and the housing 82. It should be noted that the grease zerk 80 may not be essential; however, it is preferable. 
     To keep the cradle assembly 70 from separating from the attachment face 35, particularly at the lower portion 79 thereof, the cradle assembly 70 includes a retaining means 95 interacting between the lower portion 79 of the cradle assembly 70 and the attachment face 35. As can be best seen in FIG. 3 and FIG. 6, the lower portion 79 includes left and right slot shaped holes 96 through which a bolt and washer assembly 97 extends to thread into the attachment face 35, or in the alternative, held in place on the attachment face 35 by a nut 98. The slot shaped holes 96 allow rotation of the cradle assembly 70 while the bolt and washer assembly 97 keeps the cradle assembly 70 in close proximity to the attachment face 35. A spacer 99, shown in the form of a plastic block, keeps the cradle assembly 70 and the attachment face 35 from coming into sliding contact with each other. It should be further realized by one skilled in the art that other forms of spacers, such as a roller, could be similarly used. 
     To operate the lateral float mechanism 60, the pivot control means 90 is manipulated to effect the desired rotation of the cradle assembly 70 about the pivot means 80. The header 20, being attached to the cradle assembly 70, is rotatable therewith and is positionable to correspond to the slope of the ground. Total rotation of the cradle assembly 70 and attached header 20, from a full left rotation to a full right rotation, is in the range of six to eight degrees, representing approximately 31/2 degrees to each side of horizontal. As the cradle assembly 70 is rotated, the crop passage opening 78 therethrough becomes slightly askewed to the crop inlet opening 38 at the beginning of the feeder house passageway 36. To prevent a loss of crop material because of the askewed openings 36, 78 and because of the separation between the cradle assembly 70 and the attachment face 35 due to the presence of the spacer 99, a flexible seal 67, as can be best seen in FIG. 3, extends between the cradle assembly 70 and the front face member 50. 
     Since different crops require different angles for the cutting means 22 relative to the ground for best cutting efficiency and least crop loss, the cutting means/ground angular relationship can be selectively adjusted by manipulating the stabilizing means 55 such that the front face member 50 is rotated in a fore-and-aft direction, thereby affecting a corresponding angular change between the cutting means 22 and the ground. Providing a pivot point at the axis corresponding to the driven shaft 44 of the endless apron conveyor 41 keeps the header 20 at a constant distance from the endless apron conveyor 41 so that the efficiency of the crop conveying means 40 to engage the crop material and transport it rearwardly is not impaired. 
     By providing a combine with both a lateral float mechanism 60, in the form of a cradle assembly 70, and a front face member 50, one skilled in the art should readily realize that a very flexible header mounting combination is obtained. Furthermore, an adjustment of the distance between the cutting means 22 and the ground can be easily obtained by manipulation of the header lift means 48 (e.g. extension and retraction of the hydraulic cylinder), which extends between the feeder house 30 and the base unit 12. 
     It will be understood that various changes in the details, material, steps and arrangement of parts which have been described and illustrated in order to explain the nature of the invention, will occur to and may be made by those skilled in the art upon a reading of the disclosure within the principles and scope of the invention.