Wearable drug delivery device
A modular, semi-disposable patch pump for conducting a medical therapy includes a pump unit releasably connected to a reservoir unit by means of a bayonet connection; and a housing design for supporting both reliability and ease of use of said connection.
1. A patch pump comprising a reservoir unit and a pump unit,
wherein the reservoir unit comprises:
a reservoir unit housing, a base plate, an adhesive patch assembly for attaching the patch pump to a patient, a reservoir comprising a reservoir outlet, a needle assembly configured to provide a drug from the reservoir outlet into the patient, and an inserter assembly configured to insert a portion of the needle assembly into the patient using energy stored in the reservoir unit and/or the pump unit,
wherein:
the reservoir outlet is fluidly connected to the needle assembly,
the reservoir is fluidly connected to a pump mechanism configured to pump the drug out of the reservoir, and
the base plate is mounted on the adhesive patch assembly,
wherein the pump unit comprises:
a pump unit housing, an electrical power source, a drive unit comprising a pump driving means to drive the pump mechanism, and a control unit,
wherein:
the pump unit is configured to be releasably attachable to the reservoir unit by a bayonet connection, the bayonet connection comprising a rotational axis defining an opening side on the patch pump where the pump unit is configured to be lifted away from the base plate to open the bayonet connection, and
wherein the base plate comprises a base plate extension which extends in a plane of the base plate towards the pump unit along a protection distance of about 5 mm and substantially covers an area from a side wall of the reservoir unit housing at the opening side at least to the rotational axis of the bayonet connection to prevent unintended detaching of the pump unit.
2. The patch pump according to claim 1 , wherein a mechanical interface between the pump unit and the reservoir unit comprises a locking mechanism configured to prevent unintended detachment.
3. The patch pump according to claim 1 , wherein the base plate comprises a cut-out configured for detachment of the pump unit.
4. The patch pump according to claim 3 , wherein a length of the cut-out along an edge of the base plate ranges from 5 mm to 30 mm, and a width of the cut-out ranges from 1 mm to 10 mm.
5. The patch pump according to claim 4 , wherein the length of the cut-out along the edge of the base plate ranges from 15 mm to 25 mm, and the width of the cut-out ranges from 3 mm to 5 mm.
6. The patch pump according to claim 2 , where the locking mechanism comprises a latch operated by opening or closing the bayonet connection.
7. The patch pump according to claim 6 , wherein the latch comprises locking spring configured to interact with a locking structure.
8. The patch pump according to claim 1 , wherein the inserter assembly is driven by mechanical energy.
9. The patch pump according to claim 8 , wherein the mechanical energy is generated by a mechanically expandable or shrinkable component, or by a pre-loaded insertion spring.
10. The patch pump according to claim 1 , wherein the inserter assembly is driven by electrical energy.
11. The patch pump according to claim 10 , wherein the electrical energy is generated by a rechargeable battery integrated in the pump unit, by a battery integrated in the reservoir unit, or by another battery.
12. The patch pump according to claim 1 , wherein the pump mechanism comprises a plunger.
13. The patch pump according to claim 1 , wherein the pump driving means comprises a threaded rod.