SYRINGES AND INJECTORS WITH CAPACITIVE SENSING LOCKS AND METHODS OF MAKING AND USING SAME
An injecting device comprises a reservoir for containing a medicament, a needle in communication with the reservoir and configured to deliver the medicament to a patient's body, a capacitance sensor disposed adjacent to the needle, and a plunger rod assembly comprising a housing and a piston, the housing and piston being configured to transition between a locked condition in which the piston and the housing are coupled to move together, and an unlocked condition in which the piston is capable of translating relative to the housing.
1 . An injecting device comprising:
a reservoir for containing a medicament;
a needle in communication with the reservoir and configured to deliver the medicament to a patient's body;
a capacitance sensor disposed adjacent to the needle; and
a plunger rod assembly comprising a housing and a piston, the housing and piston being configured to transition between a locked condition in which the piston and the housing are coupled to move together, and an unlocked condition in which the piston is capable of translating relative to the housing.
2 . The injection device of claim 1 , wherein the piston comprises a first portion and a second portion, the first portion having a first diameter and the second portion forming an enlarged cylindrical casing with a second diameter, the second diameter being greater than the first diameter.
3 . The injection device of claim 2 , further comprising a solenoid in communication with the capacitance sensor.
4 . The injection device of claim 3 , further comprising a latch operatively coupled to the solenoid.
5 . The injection device of claim 4 , wherein the latch comprises at least one finger.
6 . The injection device of claim 4 , wherein the latch comprises a plurality of fingers.
7 . The injection device of claim 4 , wherein the latch is disposed within the piston and translatable relative thereto.
8 . The injection device of claim 4 , further comprising a spring disposed within the housing, the spring being compressible by the piston.
9 . The injection device of claim 4 , wherein the piston comprises at least one opening for receiving a portion of the latch.
10 . The injection device of claim 4 , wherein the latch is coupled to the solenoid via a pin that travels through the latch.
11 . The injection device of claim 4 , wherein the latch and the pin are unitarily formed.
12 . An injecting device comprising:
a reservoir for containing a medicament;
a needle in communication with the reservoir and configured to deliver the medicament to a patient's body;
a capacitance sensor disposed adjacent to the needle; and
a plunger rod assembly comprising a housing, a piston and a solenoid configured to transition the plunger rod assembly between a locked condition in which the piston and the housing move together, and an unlocked condition in which the piston is capable of translating relative to the housing.
13 . The injection device of claim 12 , further comprising a latch coupled to the solenoid.
14 . The injection device of claim 13 , wherein the latch comprises at least one finger.
15 . The injection device of claim 13 , wherein the latch comprises two, three, four or five fingers.
16 . A method of administering a medicament, comprising:
providing an injecting device comprising: (i) a reservoir for containing a medicament, (ii) a needle in communication with the reservoir and configured to deliver the medicament to a patient's body, (iii) a capacitance sensor disposed adjacent to the needle, and (iv) a plunger rod assembly comprising a housing and a piston, the housing and piston being configured to transition between a locked condition in which the piston and the housing are coupled to move together, and an unlocked condition in which the piston is capable of translating relative to the housing;
measuring a first baseline capacitance via the capacitance sensor when the needle is not in physical contact with a patient's body; and
measuring a second capacitance via the capacitance sensor when the needle is in physical contact with the patient's body; and
determining if the needle was inserted in the patient's body based on a difference between the first baseline capacitance and the second capacitance.
17 . The method of claim 16 , wherein the plunger rod assembly of (iv) further comprises (v) a solenoid in communication with the capacitance sensor of (iii); and (vi) a latch operatively coupled to the solenoid.
18 . The method of claim 16 , wherein measuring a second capacitance comprises continuously measuring the second capacitance and comparing it to the first baseline capacitance until the difference between the first capacitance and the second capacitance is above a predetermined threshold.
19 . The method of claim 16 , further comprising transitioning the plunger rod assembly to the locked condition when the needle is in contact with the patient's body.
20 . The method of claim 16 , further comprising transitioning the plunger rod assembly to the unlocked condition when the needle is not in contact with the patient's body.