Patent Application
20070044890
Soybean straw or stalks typically is a waste material following the bean harvest. Bean straw is normally tilled back into the ground, but the straw has very little nutrient benefits for the soil. Therefore, it is desirable to find a commercial use for soybean straw.
Straw from other agricultural grains has been used to make fiberboard by coating the straw with resin and compressing the composite material into boards. However, soybean straw differs from grain straw in that soybean straw includes pith within the straw, that is not present in other grains. Therefore, the machines and processes used to make fiberboard or strandboard from grain straw is not useful for soybean straw or other pith-containing plant stalks.
Accordingly, a primary objective of the present invention is the provision of the machine for conditioning soybean straw.
Another objective of the present invention is the provision of the machine for removing pith from soybean straw so that the straw can be used in fiber board.
A further objective of the present invention is the provision of a machine which aligns soybeans straw longitudinally for lengthwise cutting and crushing.
Still another objective of the present invention is the provision of a machine which automatically removes pith from soybean straw.
Another objective of the present invention is the provision of a process for removing pith from soybean straw.
These and other objectives have become apparent from the following description of the invention.
The machine for conditioning soybean straw according to the present invention includes a pair of compression rollers to compress soybean straw, a pair of cutting rollers to cut the straw lengthwise, and a pair of crushing rollers to crush the cut straw and thereby remove pith from the straw. The cutting rollers rotate at a higher RPM then the compression rollers, and the crushing rollers operate at a higher RPM then the cutting rollers, such that the straw is pulled through the machine. The two crushing rollers operate at different speeds, so as to create a sheering force on the straw passing there through. One roller in each pair of rollers is spring mounted for adjustable tension. A corrugated inlet chute aligns the straw longitudinally for introduction into the feed rollers.
The soybean straw conditioning machine of the present invention is generally designated by the reference numeral 10 in the drawings. The machine includes a frame 12 having a series of rollers 14, 16, 18, 20, 22 and 24. Each end of the rollers 14-22 are mounted at opposite ends in bearings 26. Rollers 14, 16 compress the bean straw, rollers 18, 20 cut the bean straw, and rollers 22, 24 crush the bean straw, as described in more detail below.
The top roller 14, 18 and 22 in each pair of rollers is spring mounted. More particularly, as seen in
Each roller 14-24 includes a shaft 36 A-F with a sprocket 38 A-F mounted thereon. The rollers 14-24 are rotated by a drive train including a motor 40, an enlarged wheel 42, a drive belt 44 extending between the drive shaft 46 of the motor 40 and the wheel 42, and a plurality of drive chains 48 extending around the sprockets 38 A-F. The shaft 36 D includes a second sprocket 39. When the motor 40 is actuated, the belt 44 drives the wheel 42 so as to rotate the shaft 36 D in the sprockets 38 D, 39, which in turn drives the shafts 36 A, B, C, D and F via the chains 48.
As seen in
Preferably, the compression rollers 14, 16 are made from rubber and function to initially crush the soybean straw passing there through. The upper cutting roller 18 is also preferably made of rubber; while the lower cutting roller 20 is made of metal preferably steel. The bottom cutting roller 20 also includes teeth for cutting the straw lengthwise, as the straw passes longitudinally between the cutting rollers 20, 22. In a preferred embodiment, the bottom cutting roller 20 is formed from a plurality of saw blades with spacer discs between adjacent blades. The saw blades are spaced approximately one-eighth inch apart and preferably do not have an increased width at the tips (commonly known as a “set” normally found on saw blades to prevent binding). The upper cutting roller 18 preferably has grooves corresponding to the spaced apart teeth on the lower cutting roller 20, such that soybean straw cannot pass between the cutting rollers 18, 20 without being cut. The downstream crushing rollers 22, 24 are preferably made of metal. Also, the rollers 22, 24 preferably have grooves formed around the perimeter to facilitate and enhance the crushing action of the rollers 22, 24.
As seen in
An inlet chute 52 is provided on the upstream end of the frame 12. The inlet chute 52 may take various forms, and should function to direct the soybean straw longitudinally or lengthwise into the feed rollers 14, 16. For example, the inlet chute may be corrugate metal with the corrugations extending perpendicular to the axis of the rollers 14, 16.
A support tray 54 extends between the pairs of rollers 14, 16, and 18, 20. A second support tray 56 extends between the pairs of rollers 18, 20 and 22, 24. The trays 54, 56 support the straw as it moves through the machine 10. An outlet chute or bin (not shown) may be provided on the downstream end of the frame 12 to receive the cut and crushed straw from the last set of rollers 22, 24. The tray 54 preferably includes fingers extending between the cutting blades of roller 20, adjacent the spacer discs to further support the straw as it moves into contact with the cutting rollers 18, 20.
In operation, the soybean straw is introduced into the inlet chute 52 for longitudinal feeding into the compression rollers 14, 16, which compress the straw. The straw then moves along the tray 54 into the cutting rollers 18, 20, which cut the straw longitudinally along its length. The straw is then carried by the tray 56 into the crushing rollers 22, 24, which further crushes the cut straw and pulverizes the pith which is then easily separable from the cut and crushed straw. The processed or conditioned straw with the pith removed therefrom is then ready to be used for the creation of fiberboard, including the coating with resin on both the inside and outside surfaces of the conditioned straw. A preferred method of manufacturing fiberboard from the de-pithed soybean straw is described in Applicant's co-pending application, Ser. No. ______ entitled Agricultural Stalk Strandboard.
It is understood that the machine 10 of the present invention can be used for other types of non-wood plant stalks that have pith to be removed. Such stalks include cotton and bassage, which can be de-pithed with the machine 10 for use in creating fiberboard or strandboard.
The invention has been shown and described above with the preferred embodiments, and it is understood that many modifications, substitutions, and additions may be made which are within the intended spirit and scope of the invention. From the foregoing, it can be seen that the present invention accomplishes at least all of its stated objectives.
