Fluid conduit insertion devices
Disclosed herein are techniques related to insertion of a fluid conduit (e.g., tubing connected to a fluid reservoir or a cannula sharing a pre-assembled fluid pathway with such tubing). In some embodiments, an insertion mechanism may include one or more springs (e.g., a torsion spring or a compression spring). The one or more springs may cause a trocar or a trocar slider to pierce tissue and insert the fluid conduit. The one or more springs may further cause the trocar or the trocar slider to be removed from the tissue.
1 . An insertion mechanism, comprising:
a first compression spring and a second compression spring, wherein each of the first and second compression springs is configured to exert a respective force based on a difference between a compressed state and an uncompressed state, wherein one of the first compression spring or second compression spring is arranged radially within the other of the first compression spring or second compression spring; and
an insertion assembly including:
a conduit carrier including a first opening through which extends a cannula and a second opening through which extends a portion of a tubing connected to a fluid reservoir, wherein at least one of the first compression spring or second compression spring is arranged around the conduit carrier; and
a trocar slidably disposed within the cannula and configured to pierce tissue,
wherein the conduit carrier, the portion of the tubing, and the trocar are configured to move in a first direction from a first position to a second position in response to the force exerted by the first compression spring, and
wherein the trocar is configured to move in a second direction opposite the first direction in response to the force exerted by the second compression spring.
2 . The insertion mechanism of claim 1 , further comprising a trigger mechanism configured to control movement of the conduit carrier and the trocar from the first position to the second position.
3 . The insertion mechanism of claim 1 , wherein the trocar is configured to return to the first position while the conduit carrier remains in the second position.
4 . The insertion mechanism of claim 1 , wherein the second compression spring is configured to return the trocar to the first position.
5 . The insertion mechanism of claim 4 , wherein the second compression spring is coupled to the trocar.
6 . The insertion mechanism of claim 4 , wherein the trocar is a solid needle integrated with the second compression spring.
7 . The insertion mechanism of claim 1 , wherein the second compression spring is configured to move the trocar outside of the cannula.
8 . The insertion mechanism of claim 1 , wherein the conduit carrier further includes a third opening in which a trocar seal is disposed, and wherein the trocar is slidably disposed within the trocar seal.
9 . The insertion mechanism of claim 8 , wherein a distal end of the trocar moves to a location within the trocar seal when the trocar returns to the first position while the conduit carrier remains in the second position.
10 . An infusion pump system, comprising:
an insertion mechanism, including:
a first compression spring and a second compression spring, wherein each of the first and second compression springs is configured to exert a respective force based on a difference between a compressed state and an uncompressed state, wherein one of the first compression spring or second compression spring is arranged radially within the other of the first compression spring or second compression spring; and
an insertion assembly including:
a conduit carrier including a first opening through which extends a cannula and a second opening through which extends a portion of a tubing connected to a fluid reservoir, wherein at least one of the first compression spring or second compression spring is arranged around the conduit carrier; and
a trocar slidably disposed within the cannula and configured to pierce tissue,
wherein the conduit carrier, the portion of the tubing, and the trocar are configured to move in a first direction from a first position to a second position in response to the force exerted by the first compression spring, and
wherein the trocar is configured to move in a second direction opposite the first direction in response to the force exerted by the second compression spring.
11 . The infusion pump system of claim 10 , further comprising a trigger mechanism configured to control movement of the conduit carrier and the trocar from the first position to the second position.
12 . The infusion pump system of claim 10 , wherein the second compression spring is configured to return the trocar to the first position.
13 . The infusion pump system of claim 12 , wherein the second compression spring is coupled to the trocar.
14 . The infusion pump system of claim 12 , wherein the trocar is a solid needle integrated with the second compression spring.
15 . The infusion pump system of claim 10 , wherein the second compression spring is configured to move the trocar outside the cannula.
16 . The infusion pump system of claim 10 , wherein the conduit carrier further includes a third opening in which a trocar seal is disposed.
17 . The infusion pump system of claim 16 , wherein a distal end of the trocar moves to a location within the trocar seal when the trocar returns to the first position while the conduit carrier remains in the second position.
18 . A method for operating an insertion mechanism of an insulin infusion system, the method comprising:
moving a trocar and a conduit carrier in a first direction from a first position to a second position in response to a force exerted by a first compression spring, the conduit carrier including a first opening through which extends a cannula and a second opening through which extends a portion of a tubing connected to a fluid reservoir, the trocar blocking a connection between the cannula and the tubing; and
moving the trocar in a second direction opposite the first direction while leaving the conduit carrier in the second position in response to a force exerted by a second compression spring, thereby permitting the connection between the cannula and the portion of the tubing
wherein at least one of the first compression spring or second compression spring is arranged around the conduit carrier.
19 . The method of claim 18 , wherein moving the trocar from the first position to the second position causes the trocar to pierce tissue and insert the cannula in the tissue.
20 . The method of claim 19 , wherein the conduit carrier further includes a third opening in which a trocar seal is disposed, and wherein moving the trocar in the second direction includes moving a distal end of the trocar to a location within the trocar seal.