Patent ID: 7523709

Claim:
An anhydrous ammonia fertilizer applicator comprising: a soil cutting knife with a cutting knife upper end connectable to a tool bar and a cutting knife lower end that penetrates soil, a metal injection tube having an injection tube inside diameter, an injection tube outside diameter, an injection tube upper end with an injection tube top end surface, an injection tube lower end, with an injection tube bottom end surface attached to the soil cutting knife with the injection tube lower end positioned behind and above the cutting knife lower end; a plastic discharge tube having a discharge tube inside diameter, a plastic tube outside diameter, a plastic tube upper end and a plastic tube lower end with a plastic tube bottom surface and wherein the plastic tube outside diameter is smaller than the injection tube inside diameter thereby forming an air chamber inside the metal injection tube and outside the plastic discharge tube; a plastic tube retainer assembly including a metal swaged cap with a cap cylindrical upper portion, a cap cylindrical portion bottom surface, a conical cap lower portion integral with the cap cylindrical upper portion with a conical cap bottom end having a minimum diameter, a swaged cap bore passing through the cap cylindrical upper portion and through the conical cap lower portion and wherein the swaged cap bore is coaxial with the cap cylindrical upper portion and the conical cap lower portion, a metal retainer ring with a cylindrical retainer ring outer surface, a retainer ring bottom positioning surface, a retainer ring passage coaxial with the cylindrical retainer ring outer surface and wherein the retainer ring passage includes a lower passage cylindrical portion with a cylindrical bore diameter that exceeds a swaged cap bore diameter, a central passage portion swage surface, and an upper passage portion that receives the conical cap lower portion of the metal swaged cap; wherein the plastic discharge tube extends through the swaged cap bore, the conical cap lower portion is received in the retainer ring passage, the central passage portion swage surface deforms the swaged cap bore and locks the plastic discharge tube in a fixed position in the swaged cap bore; and wherein the retainer ring bottom positioning surface sits on the injection tube top end surface, the plastic tube lower end extends down into the metal injection tube and the plastic tube bottom surface is adjacent to the injection tube bottom end surface; a flexible plastic fertilizer delivery hose with a hose discharge end telescopically received on the cylindrical retainer ring outer surface and telescopically received on the injection tube upper end, a top hose clamp clamping the hose discharge end to the cylindrical retainer ring outer surface and a bottom hose clamp clamping the hose discharge end to the injection tube upper end.