Woodward Chaffy Seed Classifier
2000: Harvested seed is placed in hopper (top) and metered to preconditioning
chamber (black cylinder, left). After fuzzy appendages are removed, seed moves
in air stream to classifier unit (atop preconditioning chamber). As seed exits
classifier it is separated into quality seed classes. (image courtesy ARS
Southern Plains Range Research
Invention Streamlines Cleaning of Chaffy
Seed By Luis
March 14, 2003
A seed cleaner that smoothly conditions and separates some of
the toughest seeds to harvest has been invented by an
Agricultural Research Service scientist
in conjunction with private industry.
The invention, named the Woodward Chaffy Seed Classifier 2000,
is a three-phase apparatus that meters, preconditions and classifies seed. It
was developed by the late Chester L. Dewald, formerly a research agronomist at
the ARS Southern Plains Range Research
Station in Woodward, Okla., and Victor A. Beisel, an agricultural engineer
with Aaron's Engineering, a private firm based in Fargo, Okla.
The cleaner-classifier is effective with hard-to-process chaffy
seed, such as Texas bluegrass. The apparatus has attracted interest from
private firms regarding a cooperative research and development agreement with
ARS, the U.S. Department of Agriculture's
chief scientific research agency.
Chaffy grass seed is usually a mix of stems, leaves, chaff,
lint, fuzz and other trash that forms a tangle that complicates uniform
dispensing and placement of seed during planting. Currently, cleaning and
sorting chaffy seed without damage is a costly process. Usually a hammer mill
is used to chop or break up stems, followed by cleaning treatments to remove
The new cleaner-classifier draws in unprocessed seed with an
auger and transfers it to a preconditioning unit that removes the extra
material. Next, it moves the mass to a classifying unit that separates unwanted
matter by lifting it into a separate path with the use of an airflow.
The device then separates the unlifted seeds into quality
classes, based upon their densities, by hurling them into a collection area.
Since denser, higher-quality seeds travel farther, they land toward the rear of
the collection area.
This is the last of several patents related to seed harvesting,
cleaning and classifying that Dewald and Beisel developed during 22 years of