TRANSCUTANEOUS ANALYTE SENSORS, APPLICATORS THEREFOR, AND ASSOCIATED METHODS
The present embodiments relate generally to applicators of on-skin sensor assemblies for measuring an analyte in a host, as well as their method of use and manufacture. In some aspects, an applicator for applying an on-skin sensor assembly to a skin of a host is provided. The applicator includes an applicator housing, a needle carrier assembly comprising an insertion element configured to insert a sensor of the on-skin sensor assembly into the skin of the host, a holder releasably coupled to the needle carrier assembly and configured to guide the on-skin sensor assembly while coupled to the needle carrier assembly, and a drive assembly configured to drive the insertion element from a proximal starting position to a distal insertion position, and from the distal insertion position to a proximal retraction position.
1 . An applicator for applying an on-skin sensor assembly to a skin of a host, the applicator comprising:
a first body releasably coupled to a needle;
a second body releasably coupled to the first body by a frictional engagement;
a spring configured to provide a first force to the first body and second body, the first force driving the first body and second body in a distal direction; and
wherein the frictional engagement is configured to be decoupled by a counter force applied to the on-skin sensor assembly in an opposite direction of the first force.
2 . The applicator of claim 1 , further comprising at least one retention element configured to frictionally couple the second body to the first body.
3 . The applicator of claim 2 , wherein the at least one retention element is formed integral with the second body.
4 . The applicator of claim 3 , wherein the at least one retention element is frictionally engaged against a wall of the first body.
5 . The applicator of claim 4 , wherein the counter force decouples the frictional engagement by displacing the at least one retention element from the wall of the first body.
6 . The applicator of claim 5 , wherein the wall is a backstop.
7 . The applicator of claim 5 , wherein the wall is configured to prevent the at least one retention element from deflecting.
8 . The applicator of claim 2 , wherein the frictional engagement is decoupled by the counter force exceeding a force threshold.
9 . The applicator of claim 8 , wherein the force threshold is determined by the frictional force between the at least one retention element and the first body.
10 . The applicator of claim 9 , wherein the threshold is at least 0.5 lbf.
11 . The applicator of claim 9 , wherein the threshold is at least 1 lbf.
12 . The applicator of claim 1 , wherein the first body is configured to retract in a proximal direction upon decoupling of the frictional engagement.
13 . The applicator of claim 12 , further comprising a second spring, the second spring configured to drive the first body in a proximal direction.
14 . The applicator of claim 13 , wherein the second spring is retained from release by at least one retention element of the second body.
15 . The applicator of claim 1 , wherein the decoupling of the frictional engagement is configured to be independent of a distance between the on-skin sensor assembly and a distal end of the applicator.
16 . The applicator of claim 15 , wherein the first body is configured to retract independent of the distance between the on-skin sensor assembly and the distal end of the applicator.
17 . The applicator of claim 1 , wherein the counter force applied to the on-skin sensor assembly is provided by the skin of the host opposing the first force.
18 . The applicator of claim 17 , wherein an interior of the applicator is configured to allow the skin of the host to reside within the interior.
19 . The applicator of claim 1 , wherein the needle is configured to be inserted into the skin a predetermined depth.
20 . The applicator of claim 1 , wherein the frictional engagement is configured to decouple at a range of distances between the on-skin sensor assembly and a distal end of the applicator.