Row crop attachment for combines
TECHNICAL FIELD 
     This invention relates to headers for forage harvesters in general, and particular concerns a yield-improving row crop attachment for combines. 
     BACKGROUND ART 
     In the harvesting of crops with combines and similar agricultural machinery, a certain percentage of the crop is left in the field by the machine thereby contributing to reduced overall crop yield. This unrecovered percentage varies depending upon the type of crop harvested; for example, very little loss occurs in the harvesting of wheat, whereas substantial crop losses may occur with the machine harvesting of soybeans. 
     Indeed, in the harvesting of soybeans and similar crops, the material loss percentage is excessively high, and under certain weather conditions may result in prohibitive financial loss to the farmer. In this regard, since soybeans are normally harvested after the foilage drops from the stalk and the plant is thoroughly dry, the beans are relatively easily separated from the stalk making them particularly susceptible to field loss due to mechanical action of the harvester. It has been found that the reciprocable sickle of the combine creates a shattering action in the bean stalks which in turn effects premature separation of the beans from the supporting stalks and resultant loss of beans which do not overlie bean-receiving pans at the time of separation. 
     Numerous efforts have been made to improve the efficiency of bean harvesters. One approach has been to provide a low lying, floating cutter bar such that the bean stalks may be severed close to the ground thereby reducing the degree of shattering induced by the reciprocating sickle. 
     Another approach attempting to solve the problem described above is shown in U.S. Pat. No. 3,812,661 issued to Baker, and entitled &#34;Harvesting Machine With Crop Saving Attachment&#34;. This patent shows the use of crop-catching pans pivotally supported forwardly of the combine sickle for salvaging beans which are shattered from the stalk by the cutting action. However, the device has certain shortcomings, particularly with respect to bean loss in the area between the catchers. 
     DISCLOSURE OF INVENTION 
     The present invention overcomes the field loss problem with row-planted bean crops and the like by the provision of crop-catching structure arranged and disposed to present a substantially continuous horizontal expanse forwardly of the sickle for salvaging beans which are prematurely separated from the stalk by action of the harvester. The structure includes multiple crop-receiving pans adapted to be mounted in parallel, laterally spaced relation along the combine cutter bar for defining a plurality of fore-and-aft extending, stalk-receiving throats serving to guide the stalks to the sickle. 
     Each of the fore-and-aft extending throats is variably constricted by a pair of opposed, yieldably biased wings shiftable to and from a position closing the throat. As the harvester advances along rows of crops, the respective pairs of wings are parted sufficiently to permit passage of the stalks through the throats, yet the spread between the wings in each pair is held to a minimum dimension by virtue of the wing pans being biased toward their throat-closing positions. Hence, the area immediately forward of the sickle has a virtually continuous bean-catching structure supported beneath the beans for salvaging any of the latter which may be prematurely separated from the stalks. 
     A forwardly extending snout may be mounted on each pan for lifting fallen stalks and for guiding the stalks into the throats leading to the sickle. Additionally, each pan may be provided with a skid adapted to be disposed below the combine cutter bar for protecting the latter against ground engagement and for diverting groundlying trash away from the sickle. 
    
    
     BRIEF DESCRIPTION OF DRAWING 
     In the drawing: 
     FIG. 1 is a fragmentary top plan view of a row crop attachment assembly constructed in accordance with the principles of the present invention and shown mounted on a conventional cutter bar; 
     FIG. 2 is an enlarged, fragmentary, bottom plan view of a typical divider unit in the assembly with portions thereof broken away to reveal details of construction; 
     FIG. 3 is an enlarged, fragmentary, top plan view of the divider unit with portions thereof broken away to reveal details of construction; 
     FIG. 4 is an enlarged, fragmentary, side elevational view of the unit with portions thereof broken away and shown in section to reveal details of construction; 
     FIG. 5 is an enlarged, fragmentary, cross-sectional view taken along line 5--5 of FIG. 3; 
     FIG. 6 is an enlarged, fragmentary, cross-sectional view taken along line 6--6 of FIG. 3; and 
     FIG. 7 is an enlarged, fragmentary, cross-sectional view taken along line 7--7 of FIG. 3. 
    
    
     BEST MODE FOR CARRYING OUT THE INVENTION 
     In FIG. 1 there is shown a row attachment assembly 10 mounted on a cutter bar 12 which in turn extends transversely across the front of a forage harvester (not shown). The attachment assembly 10 comprises a plurality of forwardly projecting divider units 14 positioned at predetermined spaced locations along the length of the cutter bar 12 corresponding to the spacing between the rows of crops to be harvested (represented by broken lines in FIG. 1). Opposite ends of the assembly 10 are provided with half divider units 16 as will be described in further detail hereinbelow. 
     As shown in FIGS. 2-4, the cutter bar assembly 12 includes an elongate support beam 18 extending transversely of the harvester, a sickle assembly 20 supported on the forward edge of the beam 18 and a main pan 22 mounted over the beam 18 behind the sickle assembly 20 for supporting crops severed by the latter prior to their being urged rearwardly by the reel of the harvester. The sickle assembly may be provided with guards 24 of a conventional design for protecting against damage from contact with rocks or groundlying trash. The sickle assembly 20 and guards 24 are releasably attached to the beam 18 by bolts 26 which mate with prelocated apertures spaced along the length of the beam 18. As shown for example in FIG. 4, the sickle assembly is normally carried at an upward incline fore-to-aft when properly mounted on the beam 18. 
     Each divider unit 16 is provided with a crop-receiving pan 28 having a forwardly facing front edge 30, an apertured rear edge 32 adapted to be mounted on the beam 18, and a pair of opposed side edges 34 extending fore-and-aft between the front and rear edges 30, 32. The pan 28 is provided with underlying ribs 36 each terminating at a rearmost incline mounting block 38 (shown only in FIG. 6) cooperable with elongate mounting bolts 39 to support the pan 28 on the beam 18 in a normally horizontally disposed position as opposed to the inclined orientation of the assembly 20. A pair of lower supports 40 on the underside of the pan 28 are also adapted to be secured by the bolts 39 to augment the securement between the beam 18 and the divider unit 14. 
     A pair of elongate, crop-catching wings 42, 44 are mounted on the pan 28 for swinging movement about spaced upright axes by pivot mountings 46, 48 respectively. The mountings 46, 48 are spaced forwardly of the sickle assembly 20 and each is disposed adjacent a respective side edge 34 such that the wings 42, 44 are swingable in a generally horizontal plane outwardly beyond the respective edges 34. 
     As shown for example in FIG. 3, the wings 42, 44 are virtual mirror images of one another, each having a forward end 50 associated with the respective mountings 46, 48; a rear end 52 normally overlying the sickle assembly 20, an outermost, upturned lateral edge 54 extending between the ends 50, 52; and an opposed inner downturned lateral edge 56. As illustrated in the drawings, the lateral edges 54 of each wing 42, 44 angle inwardly as ends 50 are approached to present a slight forward taper for a purpose to be described. A stop 58 (and only one of which is shown in FIG. 3) is provided for each of the wings 42, 44 to define limits of swinging movement as illustrated in FIG. 3. Additional rigidity for the wings 42, 44 may be provided by stiffening ribs 60 or similar structure. 
     Considering now FIG. 7, there are shown the details of construction for the pivot mounting 46, it being understood that mounting 48 is identically configured. An upwardly projecting cylindrical nub 62 on the pan 28 is received within a ball bearing 64 carried in a tubular boss 66 on the wing 42. The nub 62 has a central threaded aperture which mates with a retaining bolt and washer assembly 68 such that the wing 42 may be removed from the pan 28 as desired. 
     Each of the wings 42, 44 is provided with a coil spring 70 extending between end 50 and the front edge 30 of pan 28 as shown in FIG. 3. The arrangement of the springs 70 is such that each of the wings 42, 44 is biased outwardly in a direction extending beyond the respective side edges 34. 
     The units 14 are each provided with a forwardly tapered snout 72 mounted on the front edge 30 of the pan 28 by a pin hinge 74 to permit up and down swinging movement between the extreme positions shown in FIG. 4. The snout 72 serves to lift fallen stalks as well as to gently guide the stalks to the area between adjacent divider units 14. Additionally, the units 14 have ground engaging skids 73 for protection against damage to the underside of the attachment assembly 10 from rocks and ground trash. 
     Considering again FIG. 1, the crop-receiving pans 28 are preferably mounted in spaced relation along the length of cutter bar 12 to define a plurality of fore-and-aft extending, stalk-receiving throats 76 therebetween. It is noted that the throats 76 are variably constricted by wings 42, 44 of adjacent divider units 14. For example, the wing 44 of divider unit 14a cooperates with wing 42 of divider unit 14b to yieldably constrict the stalk-receiving throat 76b while the wing 44 of divider unit 14b cooperates with the wing 42 of divider unit 40c to constrict the throat 76c. Hence, the throats 76 are normally closed but may be opened sufficiently to allow passage of crop stalks rearwardly to the sickle assembly 20 by yielding swinging movement of the wings 42, 44 against the biasing of springs 70. 
     The half divider units 16a, 16b as shown in FIG. 1 are mirror images of one another, each representing one half of a divider unit 14 cut along its longitudinal axis of symmetry. Hence, the half divider unit 16a has a swingable, yieldably biased pan 44 which cooperates with the pan 42 of divider unit 14a to constrict the throat 76a. Similarly, the half divider unit 16b has a swingable wing 42 cooperable with the wing 44 of divider unit 14e to yieldably constrict the throat 76f. 
     INDUSTRIAL APPLICABILITY 
     As explained hereinabove, the row attachment assembly 10 is particularly adapted for use in harvesting row planted soybeans and similar crops wherein unacceptably high field loss due to machine-induced shattering has been experienced heretofore. In use, the pans 28 and wings 42, 44 of the divider units 14, 16 collectively present a substantially continuous crop-catching structure for salvaging beans which are prematurely separated from the stalk forwardly of the sickle assembly 20. 
     The attachment assembly 10 shown in FIG. 1 presents six stalk-receiving throats 76 and hence, it is adapted for harvesting six rows of soybeans in a single pass. Normally the cutter bar 12 is positioned at an elevation proximal to the ground such that the skids 73 are in contact with or spaced slightly above the ground. The harvester is maneuvered by the operator such that the rows of soybeans are received within the respective throats 76 as the harvester advances through the field. 
     Forward movement of the harvester causes the stalks to move rearwardly relative to the attachment assembly 10 such that the stalks pass through the throats 76 to the sickle assembly 20 for severing. The resistance presented by the stalks is adequate to part the cooperating wings 42, 44 a distance sufficient to allow passage of the stalks through the throats 76. In this connection, the tapers presented at ends 50 of the wings 42, 44 by the upturned outer edges 54 serve to facilitate spreading of the wings 42, 44 by the stalks as they pass rearwardly toward the sickle assembly 20. At the same time however, the biasing forces imparted by the springs 70 on the wings 42, 44 are sufficient to hold them tightly against the stalks in the throats 76 such that the crop-catching structure presented by the divider units 16 remains substantially continuous. 
     As the stalks are engaged by the sickle assembly 20, a certain amount of shattering will be imparted thereto causing separation of beans from the stalks forwardly as well as rearwardly of the assembly 20. Falling beans behind the assembly 20 will be collected on the main pan 22 and fed rearwardly by the harvester reel; beans which separate from the stalk forwardly of the sickle assembly are also salvaged by the collective structure of the pans 28 and wings 42, 44. In this connection, it is an important feature of the present invention that the underlying, crop-catching structure presented by the divider units 14, 16 is substantially continuous at all times during the harvesting process, the only discontinuities being the small variable dimension gaps between the cooperating wings 42, 44 of adjacent divider units 16 which allow rearward passage of the stalks to the assembly 20. 
     Should a field of fallen stalks be encountered, such as might be found in a rain damaged area, the snouts 72 serve to lift the stalks from the ground and guide them into the respective throats 76 as the harvester is advanced through the field. Under such conditions, the advantages of the present invention become even more apparent because more of the beans will be caused to be prematurely separated from the stalks and consequently, a larger percentage of beans which would otherwise be lost in harvesting are collected by the divider units 14, 16. 
     It is noted further that the upturned outer edges 54 also function to loss of collected beans from the sides of the wings 42, 44. The downturned inner edges 56 on the other hand, serve to preclude entrapment of beans between the pan 28 and the wings 42, 44 as the latter swing thereacross. 
     If the farmer desires to use his harvester for other crops or drill planted beans, it is but a simple matter to remove the divider units 14, 16 by releasing the bolts 36 which attach pans 28 to the beam 18. 
     From the foregoing, it will be appreciated that the present invention offers a relatively inexpensive, highly effective solution to the problem of field loss during harvesting of soybeans and crops of similar variety. All of the advantages of the present invention are accomplished without the need for modification to the harvester in any manner such that the farmer is provided with a highly versatile tool for increasing the utility of his capital equipment.