SYRINGE WITH DEACTIVATING MECHANISM Russian patent published in 2013 - IPC A61M5/50 A61M5/315 

FIELD: medicine.

SUBSTANCE: invention refers to medical equipment, namely syringe devices with a passive (automatic) deactivating mechanism which restricts the extraction movement of a piston rod after the injection to prevent reuse of the syringe. The syringe comprises a cylinder, an elongated piston rod, an annular elongation and a stop portion. The cylinder has a cylindrical side wall with an inner surface forming a chamber for retaining a fluid, an open proximal end and a distal end with a distal wall which provides a passageway for fluid into the chamber. The rod has a proximal end, a distal end and a main body extending between the proximal and distal ends. The rod is movable inside the chamber in the proximal and distal directions. The proximal end of the rod comprises a pressure piece having a proximal end, a distal end and a diameter, and the distal end of the piston rod comprises a coupling component. The annular elongation projects in the proximal direction from the proximal end of the cylinder and has a diameter greater than the diameter of the pressing piece. The stop portion has proximal and distal ends and is connected to the coupling component of the piston rod and movable relative thereto in the distal and proximal directions at a specified axial length so that when the distal end of the stop portion engages the distal wall of the cylinder, the pressure piece is enabled to pass in the distal direction into the annular elongation, so that it at least partially covers a part of the pressure piece to prevent the user's access to the pressure piece and the movement of the piston rod in the proximal direction. The coupling component of the piston rod comprises a visual indicator, which is fully visible when the coupling component of the piston rod is moved in the proximal direction relative to the stop portion. According to the second version of the syringe, the chamber has a first inner diameter. The annular elongation is designed to fit to the pressing portion, at least on a part of its length from its distal end. The distal end of the stop portion engages the distal wall of the cylinder thereby enabling the pressure portion advancing in the distal direction, while the pressure piece is provided to engage the annular elongation to be fitted that prevents the user from impacting on the pressure piece to move the piston rod in the proximal direction. In the third version, the syringe comprises an instrument preventing the extraction of the piston rod from the cylinder to prevent reuse of the syringe, when the distal end of the stop portion engages the distal wall of the cylinder, and a distal force is applied to the pressure piece; what is also provided is an instrument separating the stop portion from the coupling component when an adequate proximal force is applied to the piston force.

EFFECT: invention is automatically (passively) deactivated to prevent reuse; the production thereof is cost effective; besides, it is marked or otherwise indicated to show that the invention is deactivated or in use.

39 cl, 24 dwg