PROPORTIONING DEVICE WITH LOW RADIAL SEALING FORCES DURING STORAGE Russian patent published in 2020 - IPC A61M5/315 

FIELD: medical equipment.

SUBSTANCE: invention refers to dispensers for use in an out-patient infusion system. Dosing device (1) for use in an out-patient infusion system comprises dosing cylinder (11) and piston (12), arranged inside dispensing cylinder (11) with possibility of sliding movement along movement axis (A) and being transformable from storage configuration into operation configuration, wherein in storage configuration annular sealing element (121) of piston (12) is mechanically unloaded, and in operation configuration is pressed to inner side surface of dispensing cylinder (11) with formation of sliding seal, wherein metering device (1) comprises configuration switch (3), located at least partially in channel or seat of piston (12) with possibility of movement relative to piston (12) from storage position into operating position, performed by movement of piston (12) in proximal direction and blocking movement of configuration switch (3) in proximal direction due to interaction of configuration switch (3) and metering cylinder (11) with provision of the piston transfer from the storage configuration to the operation configuration, wherein due to said relative displacement piston (12) radially expands with pressing of annular sealing element (121) to inner side surface of metering cavity of dispensing cylinder and creation of seal, characterized in that configuration switch (3) comprises stop (32), which in the storage position is located at a distance from piston (12) in the axial direction, wherein displacement of configuration switch (3) from storage position to operation position is accompanied by movement of stop (32) towards piston (12).

EFFECT: proposed is metering device with low radial sealing forces during storage.

14 cl, 4 dwg