Inserter having two springs
The invention relates to an inserter for a medical device e.g. an infusion set or the like for intermittent or continuous administration of a therapeutical substance, such as e.g. insulin. The inserter comprises a needle hub comprising an insertion needle and two elastic elements assuring automatic insertion and automatic retraction of the insertion needle. Activation of the first elastic element ( 11 ) cause a penetrating member ( 6 A) to be inserted sub- or transcutaneously into the skin of a patient, and the second elastic element ( 12 ) cause the penetrating member ( 6 A) to be retracted from the skin of the patient. The first elastic element ( 11 ) is in an unloaded state before activation and upon activation the first elastic element ( 11 ) energizes the second elastic element ( 12 ).
1. An inserter for a medical device comprising:
a stationary part being stationary in relation to the patient during insertion and resting against the patient's skin;
a carrier body having a forward and a retracted position relative to the stationary part;
a needle hub connected with a penetrating member;
a first elastic element and a second elastic element configured such that activation of the first elastic element causes a penetrating member to be inserted sub- or transcutaneously into the skin of a patient, and the second elastic element causes the penetrating member to be retracted from the skin of the patient, the first elastic element is in an unloaded state before activation and upon activation, the first elastic element energizes the second elastic element;
a first locking member configured to releasably lock the carrier body in the retracted position;
a first release member configured to unlock the carrier body from the retracted position;
a second locking member configured to releasably lock the needle hub in a forward position relative to the carrier body;
a second release member configured to unlock the needle hub from the needle hub forward position, the needle hub being movable relative to the carrier body; and
an activator configured to activate the first elastic element.
2. An inserter for a medical device according to claim 1 , wherein the second release member automatically releases the needle hub from the carrier body when the second release member passes a release position.
3. An inserter for a medical device according to claim 2 , wherein the release member is part of the stationary part.
4. An inserter for a medical device according to claim 1 , wherein the second locking member comprises pivotally mounted arms having hooks, the hooks contacting proximal turned surfaces of the carrier body in the retracted position.
5. An inserter for a medical device according to claim 4 , wherein the pivotally mounted arms having an inclined surface are forced inwards by protruding parts of a protruding circular edge in a position where at least a portion of the carrier body, the stationary part and a housing contact the patient's skin.
6. An inserter for a medical device according to claim 1 , wherein the medical device to be inserted is either provided with a cannula extending from a proximal side of the device.
7. An inserter for a medical device according to claim 6 , wherein the cannula can be a soft cannula or a hard self-penetrating cannula.
8. An inserter for a medical device according to claim 1 , wherein the first elastic element is a spring having a spring constant k 1 and the second elastic element is a spring having a spring constant k 2 .
9. An inserter for a medical device according to claim 8 , wherein k 1 ≧2k 2 .
10. An inserter for a medical device according to claim 7 , wherein the spring constant k 1 of the first elastic element is larger than the spring constant k 2 of the second elastic element.
11. An inserter for a medical device according to claim 8 , wherein the spring constant k 1 ≧0.2 and the spring constant k 2 ≧0.09.
12. An inserter for a medical device according to claim 1 , wherein the first elastic element or the second elastic element is a helical spring.
13. An inserter for a medical device according to claim 1 , wherein the first elastic element is configured to apply force to a surface of a housing and to a surface of the carrier body and the second elastic element is configured to apply force to a surface of the needle hub and a surface of the stationary part.
14. An inserter for a medical device according to claim 13 , wherein the housing is the activator and inside the housing, the carrier body moves from the retracted to the forward position when the first elastic element is activated.
15. An inserter for a medical device according to claim 14 , wherein a first integrated part comprising the first elastic element can be separated from a second integrated part comprising the second elastic element and the penetrating needle.
16. An inserter for a medical device according to claim 15 , wherein the first integrated part is reusable and the second integrated part is disposable.
17. An inserter for a medical device according to claim 1 , wherein the medical device comprises a unit for metering a substance, an infusion part of an infusion set for delivering of a drug or a gateway for replacing multiple injections.
18. A method of sub- or transcutaneously position a medical device, the method comprising:
providing an inserter according to claim 1 ; and
sub- or transcutaneously positioning the medical device using the inserter; and
metering a substance, delivering a drug or combinations thereof.
19. The method of claim 18 , comprising fastening a medical device to a patient's skin and sub- or transcutaneously positioning a separate cannula part using the inserter.