Abstract: A hydraulic drive system provides a priority flow of hydraulic fluid to a variable rate drive system for powering the operation of the metering mechanisms before hydraulic fluid is supplied to a secondary drive mechanism for powering the operation of secondary devices, such as the fan mechanism or the loading auger. The hydraulic drive system includes a priority flow divider valve that diverts a predetermined flow rate to the variable rate drive system. The variable rate drive system includes a drive mechanism arranged in series for a plurality of metering mechanisms. The secondary drive system includes a selector valve that permits a selection between the alternative secondary devices. An alternative embodiment of the hydraulic drive system includes a counter balance valve that operates to provide a priority flow to the variable rate drive system.

Abstract: A hydraulic drive system provides a priority flow of hydraulic fluid to a variable rate drive system for powering the operation of the metering mechanisms before hydraulic fluid is supplied to a secondary drive mechanism for powering the operation of secondary devices, such as the fan mechanism or the loading auger. The hydraulic drive system includes a priority flow divider valve that diverts a predetermined flow rate to the variable rate drive system. The variable rate drive system includes a drive mechanism arranged in series for a plurality of metering mechanisms. The secondary drive system includes a selector valve that permits a selection between the alternative secondary devices. An alternative embodiment of the hydraulic drive system includes a counter balance valve that operates to provide a priority flow to the variable rate drive system.

Abstract: A control system is provided for automatically deploying the field markers on an agricultural planter in an alternating manner without requiring operator input. The control system utilizes a proximity sensor to determine whether the tool bar is coming from the lowered working position to the raised headland position or vice versa. Solenoid valves in the hydraulic circuit to the field marker actuators are activated to retract both actuators to retract the deployed one of the field markers when the tool bar is moved into the headland position. When the tool bar is returned to the working position after making a turn at the field headlands, the control system remembers which field marker had just previously been deployed and then extends the other field marker to score the field. The control system permits the operator to remain attentive to the turning of the tractor and implement at the headlands and the setting of the planting implement into the ground at the proper location for planting the crop.