Abstract: An improved bulk transfer system for an agricultural seeder or planter breaks up the central fill system into two stages for supplying a plurality of agricultural products simultaneously to an array of metering pods, each pod containing a plurality of metering assemblies. Firstly, there is a continuous transfer of agricultural product from a trailing product cart to intermediate mini tanks mounted on a central frame and located adjacent the seeding drills and plurality of metering assemblies. The pressurized mini tanks receive agricultural products on demand. Secondly, agricultural products are transferred on demand from the mini tanks to each of the corresponding metering assemblies along the seeding drill. This arrangement enables redistribution of the weight of the bulk of the product farther away from the seeding drills, allowing for greater tow-behind product volumes.

Abstract: A system to meter multiple agricultural products according to an independently prescribed rate for each in a variable-ratio blend of the agricultural products from a single opener in a plurality of such systems and openers across an applicator such as a drill. Bulk storage compartments associated with the applicator deliver multiple agricultural products to metering assemblies mounted in clusters or pods across the applicator. The agricultural products are fed from the metering assemblies, via a flow re-director, into a manifold, and then into a corresponding single opener having conduits to transport the agricultural product into the soil. Controllers independently regulate metering by the metering assemblies. The flow re-director and manifold provide blending of combinations of the agricultural products for each opener according to a field prescription.

Abstract: An air manifold system for supplying an agricultural product to a plurality of metering devices comprises a product hopper having a product flow cavity, the product cavity separated from a first plenum by an air agitator sandwiched between the first plenum and the product flow cavity. The hopper comprises a plurality of nozzles extending through a wall of the hopper. A venturi assembly is in fluid communication with at least one nozzle. A first forced air stream flows through the first plenum and the air agitator into the product flow cavity to agitate and entrain agricultural product in the first air stream, and the first air stream carries the entrained agricultural product into the nozzles. A second forced air stream flows through the venturi assembly to accelerate the first air stream and the entrained product towards and through the supply hoses connected to the nozzles.

Abstract: A system to meter multiple agricultural products according to an independently prescribed rate for each in a variable-ratio blend of the agricultural products from a single opener in a plurality of such systems and openers across an applicator such as a drill. Bulk storage compartments associated with the applicator deliver multiple agricultural products to metering assemblies mounted in clusters or pods across the applicator. The agricultural products are fed from the metering assemblies, via a flow re-director, into a manifold, and then into a corresponding single opener having conduits to transport the agricultural product into the soil. Controllers independently regulate metering by the metering assemblies. The flow re-director and manifold provide blending of combinations of the agricultural products for each opener according to a field prescription.

Abstract: A system to meter multiple agricultural products according to an independently prescribed rate for each in a variable-ratio blend of the agricultural products from a single opener in a plurality of such systems and openers across an applicator such as a drill. Bulk storage compartments associated with the applicator deliver multiple agricultural products to metering assemblies mounted in clusters or pods across the applicator. The agricultural products are fed from the metering assemblies, via a flow re-director, into a manifold, and then into a corresponding single opener having conduits to transport the agricultural product into the soil. Controllers independently regulate metering by the metering assemblies. The flow re-director and manifold provide blending of combinations of the agricultural products for each opener according to a field prescription.

Abstract: An improved roller assembly for a metering device, with reduced contact between the surface of the roller and the inner surface of the metering housing so as to reduce the areas within the roller assembly where a blockage may occur, and an improved mounting of the metering device so as to improve access to the roller assembly for maintenance. Also provided is an improved process control for driving the stepper motor of a metering device, so as to better detect the onset of a stall condition of a stepper motor and temporarily increase the torque supplied to the motor to avoid a stall condition. Additionally, an improved air manifold incorporates venturi assemblies to reduce or eliminate blockages that may occur when a local reservoir for holding a small reserve of agricultural product adjacent the metering device has reached capacity due to continual supply of product from a product hopper.

Abstract: A system to meter multiple agricultural products according to an independently prescribed rate for each in a variable-ratio blend of the agricultural products from a single opener in a plurality of such systems and openers across an applicator such as a drill. Bulk storage compartments associated with the applicator deliver multiple agricultural products to metering assemblies mounted in clusters or pods across the applicator. The agricultural products are fed from the metering assemblies, via a flow re-director, into a manifold, and then into a corresponding single opener having conduits to transport the agricultural product into the soil. Controllers independently regulate metering by the metering assemblies. The flow re-director and manifold provide blending of combinations of the agricultural products for each opener according to a field prescription.

Abstract: A system to meter multiple agricultural products according to an independently prescribed rate for each in a variable-ratio blend of the agricultural products from a single opener in a plurality of such systems and openers across an applicator such as a drill. Bulk storage compartments associated with the applicator deliver multiple agricultural products to metering assemblies mounted in clusters or pods across the applicator. The agricultural products are fed from the metering assemblies, via a flow re-director, into a manifold, and then into a corresponding single opener having conduits to transport the agricultural product into the soil. Controllers independently regulate metering by the metering assemblies. The flow re-director and manifold provide blending of combinations of the agricultural products for each opener according to a field prescription.

Abstract: A system to meter multiple agricultural products according to an independently prescribed rate for each in a variable-ratio blend of the agricultural products from a single opener in a plurality of such systems and openers across an applicator such as a drill. Bulk storage compartments associated with the applicator deliver multiple agricultural products to metering assemblies mounted in clusters or pods across the applicator. The agricultural products are fed from the metering assemblies, via a flow re-director, into a manifold, and then into a corresponding single opener having conduits to transport the agricultural product into the soil. Controllers independently regulate metering by the metering assemblies. The flow re-director and manifold provide blending of combinations of the agricultural products for each opener according to a field prescription.

Abstract: A purge system for fuel cell stack includes a purge valve to regulate exhaust from the fuel cell stack in response control signals from a controller in response to a voltage across a purge cell portion of a fuel cell stack. The purge valve is opened when the voltage across the purge cell portion falls below a defined percentage of a threshold voltage. The threshold voltage can be equal to an average cell voltage of some or all of the fuel cells of the fuel cell stack. The purge may include one or more successive openings of the purge valve of controlled purge durations.

Abstract: A fuel cell system includes fuel cells forming a fuel cell stack, having a fuel passage and an oxidant passage. A purge valve is coupled to the fuel passage to exhaust contaminants, and a controller is coupled to temporarily increase the oxidant stream flow rate through the oxidant passage, and to temporarily open the fuel purge valve, if a voltage across a pair of fuel cells is less than a defined threshold voltage. In this resuscitation step, the oxidant flow rate can be temporarily increased by increasing a duty cycle of an air compressor by approximately 50% for a duration of between approximately 5 to 10 seconds. The controller can further shut down fuel cell operation if a voltage across a pair of fuel cells is less than a defined threshold voltage in an inter-resuscitation period immediately following the resuscitation step.

Abstract: A fuel cell system includes fuel cells forming a fuel cell stack, having a fuel passage and an oxidant passage. A purge valve is coupled to the fuel passage to exhaust contaminants, and a controller is coupled to temporarily increase the oxidant stream flow rate through the oxidant passage, and to temporarily open the fuel purge valve, if a voltage across a pair of fuel cells is less than a defined threshold voltage. In this resuscitation step, the oxidant flow rate can be temporarily increased by increasing a duty cycle of an air compressor by approximately 50% for a duration of between approximately 5 to 10 seconds. The controller can further shut down fuel cell operation if a voltage across a pair of fuel cells is less than a defined threshold voltage in an inter-resuscitation period immediately following the resuscitation step.

Abstract: A purge system for fuel cell stack includes a purge valve to regulate exhaust from the fuel cell stack in response control signals from a controller in response to a voltage across a purge cell portion of a fuel cell stack. The purge valve is opened when the voltage across the purge cell portion falls below a defined percentage of a threshold voltage. The threshold voltage can be equal to an average cell voltage of some or all of the fuel cells of the fuel cell stack. The purge may include one or more successive openings of the purge valve of controlled purge durations.