DRIVE UNIT, PLUNGER ROD, DEVICE FOR MEDICATION DELIVERY AND SPRING APPLICATION Russian patent published in 2015 - IPC A61M5/24 A61M5/315 

FIELD: medicine.

SUBSTANCE: invention relates to medical equipment, namely to a drive unit for a device for medication delivery, the device for medication delivery and to the application of a spring in the device for medication delivery. The drive unit for medication delivery, made with a possibility of returning into an initial position, contains a case, a plunger rod, a drive element, intended for the displacement of the plunger rod in the distal direction to the terminal position when a dose is supplied, and a stopper. The case has the proximal end and the distal end. The plunger rod is made with a possibility of rotation relative to the case and with a possibility of displacement in the axial direction relative to the case between the proximal initial position and the distal terminal position. The drive element is made with a possibility of being brought into action for being brought into interaction with the plunger rod in order to form the first blocking means, made with a possibility of unblocking. The first blocking means can be brought into action to block the movement of the plunger rod in the proximal direction relative to the drive element. The stopper is made with a possibility of being brought into action for its bringing into interaction with the plunger rod in order to form the second blocking means, made with a possibility of unblocking. The second blocking means can be brought into action to block the movement of the plunger rod in the proximal direction relative to the case. When the drive unit is in the drive mode, the first and the second blocking means are blocked in such a way that the first blocking means and the second blocking means prevent the movement of the plunger rod in the proximal direction from the terminal position into the initial position. To transfer the drive unit from the drive mode into the mode of return into the initial position the plunger rod can be turned relative to the drive element to unblock the first blocking means. The stopper and the plunger rod can be turned with respect to each other to unblock the second blocking means. When the drive unit is in the mode of return into the initial position, the first blocking means and the second blocking means are unblocked and the possibility of the plunger rod travel in the proximal direction into the initial position is provided. The device for medication delivery contains the said drive unit and a detachable element, intended for connection with the case. The detachable element represents either a cartridge or a cartridge holder. The detachable element is made with a possibility of being brought into action to bring it into interaction with the element, intended for the provision of return into the initial position in such a way that when the detachable element in connected with the case, contact interaction/meshing of the element, intended for the provision of return into the initial position, with the case, is eliminated with an overcoming elastic biasing effort, acting on the element, intended for the provision of return into the initial position. When the detachable element is detached from the case, the element, intended for the provision of return into the initial position, is brought into contact interaction with the case under the action of the elastic biasing effort, acting on the element, intended for the provision of return into the initial position. A spring is used for the accumulation of energy for the provision of the plunger rod rotation in the second rotation direction, opposite with respect to the first rotation direction, relative to the case due to interaction with the plunger rod for displacement/tightening the plunger rod in the second rotation direction in the dose setting; for the accumulation of energy for the provision of the stopper rotation in the second rotation direction due to interaction with the stopper for the displacement of the stopper in the second rotation direction, when the blocking means is blocked; for the transmission of an effort to the stopper to provide the stopper rotation in the first rotation direction relative to the case and the plunger rod due to interaction with stopper for the displacement/tightening the stopper in the first rotation direction in unblocking the blocking means.

EFFECT: improvement of the construction.

20 cl, 16 dwg