Abstract: An actuator assembly is provided for converting rotation into linear displacement including a linear fluid dispensing tube for linear displacement. Hemispherical lugs are monolithically formed on the linear member. A primary gear includes a central bore having helix grooves formed into a surface of the central bore. The helix grooves receive the hemispherical lugs so that each helix groove mates with a respective hemispherical lug to reduce friction, so that hemispherical lugs slide smoothly within the respective helix grooves. Linear projections are formed on the exterior surface of the dispensing tube and extend longitudinally along the dispensing tube. A projecting portion has an aperture for receiving and guiding the dispensing tube through the linear displacement. Mating grooves are formed on an interior of the projecting portion for receiving and guiding the linear projections, thereby preventing the dispensing tube from rotating during travel.

Abstract: An actuator assembly is provided for converting rotation into linear displacement including a linear fluid dispensing tube for linear displacement. Hemispherical lugs are monolithically formed on the linear member. A primary gear includes a central bore having helix grooves formed into a surface of the central bore. The helix grooves receive the hemispherical lugs so that each helix groove mates with a respective hemispherical lug to reduce friction, so that hemispherical lugs slide smoothly within the respective helix grooves. Linear projections are formed on the exterior surface of the dispensing tube and extend longitudinally along the dispensing tube. A projecting portion has an aperture for receiving and guiding the dispensing tube through the linear displacement. Mating grooves are formed on an interior of the projecting portion for receiving and guiding the linear projections, thereby preventing the dispensing tube from rotating during travel.