System for controlling vertical displacement of agricultural implements into the soil
1996
Carter, L.M.
A system for maintaining the depth of a planter (or tiller) at a soil depth of optimal moisture content is provided, in which a prior art soil resistivity sensor is improved by including a negative electrode immediately behind the prior art positive electrode as the planter and electrodes extend into the ground during tractor travel over the field. The prior art positive probe is shaped to form a compact ribbon of soil therebeneath that extends from the positive to the new negative probe. This compact ribbon provides a reliable and consistent path for measuring soil resistivity at a soil zone of least electrical resistance, thereby preventing other pathways between the positive electrode and grounded parts of the planter or tiller from undesirably entering the detection system in lieu of the desired pathway of measurement. The new positive electrode, wedge-shaped above its compression zone, so as to force oncoming soil above the compression zone to flow past the electrode rather than downward, prevents commingling between surface soil and soil being compressed. A new electronic control system (a) delays the command signal to the planter height adjuster, (b) returns the planter to a pre-selected position or freeze it at its last position whenever the tractor slows down too much or stops, (c) synchronizes control of the planter height adjuster whenever another variable such as ground topography also controls the height, and (d) synchronizes control of two separate height adjusters at opposite ends of a side-by-side array of planters on a single frame.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by National Agricultural Library