Patent ID: 8535268

Claim:
A system, comprising: an elongate body defining a cavity adapted to contain a material, the elongate body comprising a first opening in communication with the cavity; a structure movable within the cavity, the structure adapted to be displaced within the cavity to expel an amount of the material from the cavity through the first opening; a lead screw comprising: a first portion coupled to the structure; a second portion; and a longitudinal axis; a ratchet gear comprising a plurality of teeth, the ratchet gear coupled to the lead screw, the lead screw being rotatable with the ratchet gear; a frame member comprising: a first pawl; and a second pawl, the first pawl and the second pawl adapted to engage teeth of the ratchet gear; and an actuator, the actuator operable to oscillate the frame member perpendicular to the longitudinal axis of the lead screw such that the first pawl and the second pawl engage the teeth of the ratchet gear in a manner so as to rotate the ratchet gear in a single direction, wherein at least a portion of the lead screw defines a channel extending parallel to the longitudinal axis, wherein the ratchet gear further comprises a protrusion, and wherein the protrusion of the ratchet gear is received into the channel.