Patent ID: 6554161
Filing Date: 2003-04-29
Classification: A61D,A61M,G01F

Abstract:
Dispensing apparatus comprising:a barrel with an inlet and an outlet and an operator actuable piston reciprocally movable in said barrel, said piston, in use, when moving away from said outlet, allowing a liquid to enter space between said piston and said outlet, and subsequent discharging movement of said piston, in use, towards said outlet causes liquid to exit said outlet, and a stroke of said discharging movement being controlled by a stop mechanism for the piston, said stop mechanism including a spiral staircase member through which liquid can pass and a staircase step abutment member carried by one of the piston and an assembly, which includes the piston, butting at the limit of said discharging movement on a step of said spiral staircase member, said abutment member being rotatable about both the barrel and spiral staircase member axes by externally accessible means to determine a stroke limiting choice of a step in the staircase to encounter the abutment member and thus the quantity of liquid to be dispensed by a single discharging movement of said piston.