Dosage measurement system
The disclosure relates to a dosage measurement system for a medicament delivery device. The medicament delivery device includes a medicament reservoir and a dispensing mechanism. The dispensing mechanism includes a dispensing member that is moveable axially to dispense medicament from the medicament reservoir. The dosage measurement system includes a sensor unit and a processor. The sensor unit is configured to measure the axial displacement of the dispensing member. The processor is configured to determine a dosage dispensed from the medicament reservoir based on the measured axial displacement of the dispensing member.
1 . A dosage measurement system for a medicament delivery device, wherein the medicament delivery device comprises a medicament reservoir and a dispensing mechanism comprising a dispensing member that is axially moveable to dispense a medicament from the medicament reservoir, wherein the dispensing member comprises a lead screw and wherein the dispensing mechanism further comprises a drive member that is configured to rotate to axially displace the lead screw relative to the drive member to dispense medicament from the medicament reservoir, the dosage measurement system comprising:
a sensor unit configured to measure an axial displacement of the lead screw, wherein the sensor unit is configured to transmit a signal such that said signal is reflected from the lead screw, the sensor unit configured to detect said reflected signal, wherein the signal is transmitted along a path L1, and the reflected signal is transmitted along a path L2, and the sensor unit is configured to measure the axial displacement based on a linear distance Y between a central axis and path L2; and
a processor configured to determine a dosage dispensed from the medicament reservoir based on the measured axial displacement of the lead screw.
2 . The dosage measurement system of claim 1 , wherein the sensor unit comprises a transmission member, the signal being transmitted through the transmission member.
3 . The dosage measurement system of claim 2 , wherein the transmission member comprises a light guide.
4 . The dosage measurement system of claim 1 , wherein the sensor unit is configured to transmit a signal that travels within the drive member.
5 . The dosage measurement system of claim 1 , wherein the sensor unit is integrated with the medicament delivery device.
6 . The dosage measurement system of claim 1 , wherein the sensor unit is removably attachable to the medicament delivery device.
7 . The dosage measurement system of claim 1 , wherein the medicament delivery device comprises an actuator that is actuatable by a user to dispense the medicament, and wherein the sensor unit is configured to be mounted to the actuator.
8 . The dosage measurement system of claim 7 , wherein the actuator comprises a space, and wherein the sensor unit is configured to be at least partially received in the space.
9 . The dosage measurement system of claim 7 , wherein the processor determines the dosage dispensed from the medicament reservoir when the actuator is actuated.
10 . The dosage measurement system of claim 9 , wherein the processor does not determine the dosage dispensed from the medicament reservoir until the actuator is actuated.
11 . The dosage measurement system of claim 7 , wherein the actuator is configured to move from a first position to a second position upon actuation, and wherein the sensor unit is configured to be mounted to the actuator to move with the actuator between the first and second positions.
12 . The dosage measurement system of claim 1 , wherein the dosage measurement system comprises a first part configured to be fixed to a medicament delivery device and a second part that is removably attachable to the first part.
13 . The dosage measurement system of claim 12 , wherein the second part comprises the processor.
14 . The dosage measurement system of claim 12 , wherein the first part comprises a transmission member of the sensor unit.
15 . The dosage measurement system of claim 12 , wherein the first part and the second part comprise engaging elements configured to ensure a rotational orientation of the first part relative to the second part when the second part is attached to the first part.
16 . A medicament delivery system, comprising:
a medicament delivery device comprising a medicament reservoir and a dispensing mechanism comprising a dispensing member that is axially moveable to dispense a medicament from the medicament reservoir, wherein the dispensing member comprises a lead screw and wherein the dispensing member further comprises a drive member that is configured to rotate to axially displace the lead screw relative to the drive member to dispense medicament from the medicament reservoir; and
a dosage measurement system comprising:
a sensor unit configured to measure an axial displacement of the lead screw, the sensor unit being configured to transmit a signal such that said signal is reflected from the lead screw, the sensor unit configured to detect said reflected signal, wherein the signal is transmitted along a path L1, and the reflected signal is transmitted along a path L2, and the sensor unit is configured to measure the axial displacement based on a linear distance Y between a central axis and path L2; and
a processor configured to determine a dosage dispensed from the medicament reservoir based on the measured axial displacement of the lead screw.
17 . The medicament delivery system of claim 16 , wherein the medicament reservoir contains the medicament.
18 . The medicament delivery system of claim 16 , wherein the sensor unit comprises a transmission member, the signal being transmitted through the transmission member.