Patents by Inventor Wayne D. Tjeerdsma

Wayne D. Tjeerdsma has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 5231940
    Abstract: An attachment for pneumatic seed planters in which a multiple of rows are planted simultaneously during a single pass of the planter. The attachment enables selected rows to be shut off by preventing seeds from being discharged in a particular row or rows such as when planting in overlapping rows which occurs when making a final pass when planting at the edge of a field. The attachment in one embodiment includes a plurality of manually positioned release wheels and in another embodiment includes a plurality of solenoid positioned release wheels which release the pneumatic pressure associated with a pressurized drum having holes aligned with the number of rows the planter will plant to selectively prevent seed from being discharged into selected tubes which lead to the planting shoes.
    Type: Grant
    Filed: March 11, 1992
    Date of Patent: August 3, 1993
    Assignee: Elton A. Rokusek
    Inventor: Wayne D. Tjeerdsma