INJECTION APPARATUS COMPRISING ROTATION PREVENTING UNIT Russian patent published in 2006 - IPC A61M5/315 A61M5/00 

FIELD: medical equipment, in particular, injection devices adapted for injection of liquid substances.

SUBSTANCE: injection apparatus has casing, piston stem, driving device for enabling feeding motion, dose setting member, progressive motion restricting device, and rotation preventing unit. Casing has reservoir for liquid substance. Piston stem is positioned for performing feeding stroke in working stroke direction axially of progressive motion direction for feeding dose of liquid substance. Dose setting member is coupled to piston stem for causing rotational dosing motion by dose setting member and piston stem around axis of progressive motion relative to each other, progressive motion causing axial progressive dosing motion of dose setting member relative to piston stem and casing. When dose setting member is in its axial end position, progressive motion restricting device is arranged opposite thereto and is axially faced. When in its end position, rotation preventing unit allows rotational dosing motion in first direction of rotation and prevents rotational dosing motion in second direction to exclude application of axial depressing force to said device upon rotational dosing motion. Reservoir module for injection apparatus has front body section, piston, piston stem, drive, dose setting member, progressive motion restricting device, and rotation preventing unit. Reservoir for liquid substance is disposed in front section. Piston is disposed within reservoir for moving in operating stroke direction toward reservoir discharge opening for feeding of substance. Piston stem acts upon said piston. Drive is connected to piston stem for moving thereof in operating stroke direction. Dose setting member and piston stem are connected to one another for controlling each other in operating stroke direction. Relative rotational dosing motion of dose setting member and piston stem around axis of progressive motion influences upon axial progressive dosing motion of dose setting member relative to piston stem and front body section. Said device restricts joint motion of piston stem and dose setting member in operating stroke direction, when the latter adjoins to said device in its front axial end position.

EFFECT: increased dosing precision.

18 cl, 22 dwg