Seed Dispenser Control

Abstract

Control apparatus for a pneumatic seed meter having a seed disc that uses a pneumatic pressure differential to hold and release seed on a rotating disc. The control apparatus is controlled to disrupt the pressure differential in an area of the rotating disc to selectively disrupt planting of seed by the seed meter to, for example, reduce overlap planting.

We claim: 
     
         1 . Control apparatus for a pneumatic seed meter, comprising:
 (a) a first chamber in communication with a source of reduced pneumatic pressure;   (b) a seed disc mounted for rotation adjacent the chamber and having a first surface that faces the chamber and an opposite, second surface facing away from the chamber;   (c) a plurality of holes in the seed disc forming seed pockets that may be occluded by seeds to generate a pneumatic pressure differential across the seed disc to hold the seeds onto the disc;   (d) a second chamber in sealing engagement with an area on the first surface of the disc subject to the pneumatic pressure differential;   (e) a valve of the second chamber moveable between an open and closed position; and   (f) an actuator operable to move the valve between an open position whereby reduced pressure is present in the second chamber to retain seed held on the seed disc in the area of the first surface of the seed disc for planting of the seed by the seen meter and a closed position whereby reduced pressure is not present in the second chamber in the area of the first surface of the seed disc to release seed from the disc in the area so that the seed is not planted by the seed meter.   
     
     
         2 . The control apparatus of  claim 1 , wherein the valve is moved between the open and closed position by a linear actuator. 
     
     
         3 . Control apparatus for a pneumatic seed meter that uses a pneumatic pressure differential to hold on a rotating disc seed picked up from a seed reservoir and release them at a later point for planting, comprising:
 (a) a control element having a sealing face and positioned radially of the rotating disc between the seed reservoir and the later point for planting; and   (b) an actuator for moving the control element into and out of sealing engagement with the rotating disc.