TRANSCUTANEOUS ANALYTE SENSORS, APPLICATORS THEREFOR, AND ASSOCIATED METHODS
The present embodiments relate generally to systems and methods for measuring an analyte in a host. More particularly, the present embodiments provide sensor applicators and methods of use with activation that implant the sensor, withdraw the insertion needle, engage the transmitter with the housing, and disengage the applicator from the housing. Systems and methods according to present principles allow for such steps to occur without significant loss of spring force, and without deleterious effects such as seal slingshotting.
1 . A sensor inserter assembly for applying an on-skin device to a skin of a host, the assembly comprising:
an applicator body;
a disposable housing releasably coupled to the applicator body;
a sharp configured to place a sensor at least partially into the skin of the host;
a resistance member operatively coupled to the disposable housing;
a separation member releasably coupled to the resistance member, the separation member being configured to prevent contact of the sharp with the resistance member;
a deployment assembly configured to cause the sharp to move from a proximal starting position to a distal insertion position during a first phase and then to a proximal retracted position during a second phase, the deployment assembly being further configured to release the separation member from the resistance member during the second phase;
a first stored energy component storing sufficient energy to drive the first phase and at least a first part of the second phase; and
a second stored energy component storing sufficient energy to drive at least a second part of the second phase.
2 . The sensor inserter assembly of claim 1 , wherein the second stored energy component stores sufficient energy to drive the second phase.
3 . The sensor inserter assembly of claim 1 , wherein the second stored energy component stores more energy than the first stored energy component.
4 . The sensor inserter assembly of claim 1 , wherein the disposable housing is configured to automatically release from the applicator body after the separation member is released from the resistance member.
5 . The sensor inserter assembly of claim 1 , wherein the disposable housing is configured to automatically release from the applicator body in response to the separation member being released from the resistance member.
6 . The sensor inserter assembly of claim 1 , wherein the resistance member is moveable relative to the disposable housing, at least after the separation member is released from the resistance member.
7 . The sensor inserter assembly of claim 1 , wherein the deployment assembly is self-reversing from the first phase to the second phase.
8 . The sensor inserter assembly of claim 1 , wherein the deployment assembly is configured to activate the second stored energy component during the second phase.
9 . The sensor inserter assembly of claim 1 , wherein the separation member is frictionally engaged with the resistance member.
10 . The sensor inserter assembly of claim 1 , wherein the separation member is slidably coupled to the resistance member.
11 . The sensor inserter assembly of claim 1 , wherein at least one of the first drive assembly and the second drive assembly is configured to convert rotational motion into linear motion.
12 . The sensor inserter assembly of claim 1 , wherein the insertion assembly comprises a cannula.
13 . The sensor inserter assembly of claim 12 , wherein the insertion member is configured to travel through the cannula as the insertion member moves distally.
14 . The sensor inserter assembly of claim 12 , wherein the resistance member is releasably coupled to the cannula.
15 . The sensor inserter assembly of claim 12 , wherein the cannula is fixed relative to the disposable housing as the insertion member moves distally.
16 . The sensor inserter assembly of claim 12 , further comprising a cam configured to rotate the cannula about an axis of the cannula.
17 . The sensor inserter assembly of claim 12 , wherein a distal end of the insertion member extends distal of the cannula when the resistance member is decoupled from the insertion assembly.
18 . The sensor inserter assembly of claim 12 , wherein the resistance member comprises a contact surface configured to engage with the cannula, the contact surface defining one or more voids between the contact surface and the cannula.
19 . The sensor inserter assembly of claim 12 , further comprising a plurality of conductive elastomeric contacts disposed within the resistance member, the conductive elastomeric contacts defining one or more voids between the contact surface and the cannula.
20 . The sensor inserter assembly of claim 19 , wherein at least a portion of the insertion assembly extends through the two conductive elastomeric contacts.
21 . The sensor inserter assembly of claim 19 , wherein the resistance member comprises a contact surface configured to engage with the cannula, and wherein the conductive elastomeric contacts define one or more voids between the contact surface and the cannula.