| CPC B29C 48/51 (2019.02) [B29C 48/252 (2019.02); B29C 48/397 (2019.02)] | 16 Claims |

|
1. An apparatus for dispensing a composition, the apparatus comprising:
a barrel having an inlet and an outlet;
a screw received in the barrel, the screw having a distal end and a shank end spaced along a longitudinal axis, and a shaft having a single helical flight disposed thereon, the shaft becoming progressively larger in diameter from the shank end to the distal end; and
a drive mechanism operatively coupled to the shank end and capable of rotating the screw within the barrel,
wherein the screw is hollow and includes one or more interior surfaces and one or more exterior surfaces, the one or more interior surfaces defining a cavity adjacent to the outlet, and wherein the screw further includes a plurality of apertures through which the cavity and the one or more exterior surfaces of the screw communicate with each other, the plurality of apertures located along a perforated portion of the cavity, and the perforated portion having a transverse dimension that increases with distance from the shank end, wherein the plurality of apertures are located on the helical flight,
wherein the perforated portion defines a hole area, representing a total cross-sectional area of the apertures per unit area of the one or more exterior surfaces, that increases with the diameter of the shaft along the longitudinal axis and the distance from the shank end.
|