Invention Streamlines Cleaning of Chaffy Seed

By Luis Pons
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 extraneous material.

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 collaboration.