US Patent 7213523 Agricultural additive dispensing apparatus

A ground working apparatus for dispensing an agricultural additive to the soil is provided. The apparatus is mounted to a tool bar that is operable to be towed across an agricultural field. The apparatus includes a coulter blade in combination with a knife element, and a conduit attached thereto operable to dispense the agricultural additive in the soil. The knife element and the coulter blade characterize a gap therebetween. The gap is defined by a forward edge of the knife element having a radius of curvature that is less than a radius of curvature of the coulter blade. The conduit in interchangeably attached by at least one conduit mount plate at the knife element.