An add-on device configured to be releasably attached to a drug delivery device comprising a housing with a reference marker and a scale drum with a zero identifier and an initial marker. The add-on device comprises a memory and a camera adapted to capture an image of the housing reference marker and the initial marker when the scale drum is in a (near) initial position. The add-on device is adapted to perform a reference offset value determination, comprising: capture an image, perform an image analysis to determine if the captured image comprises the zero identifier, if so, determine a reference offset value based on the distance between the housing reference marker and the initial marker, the reference off-set value representing the initial rotational position, and if no reference offset value is stored in the memory or if the determined reference offset value corresponds to a smaller set dose amount than a currently stored value, store in the memory the determined reference offset value.

Sensing systems are disclosed for determining the relative rotational movements of members of a medication delivery device which are proportional to the amount of a dose set and delivered by the medication delivery device. The sensing system comprises a first sensor component secured to a first member and a second sensor component secured to a second member. During dose setting, the second member is coupled to a third member which rotates relative to the first member in proportion to the dose set. During dose delivery, the second member is coupled to a fourth member which rotates relative to the first member in proportion to the dose delivered. The sensing system separately detects the relative rotational positions of the first and second sensor components during dose setting and dose delivery, and provides outputs used to determine the amounts of the set and delivered doses. The sensing system outputs this information to a controller which determines the amount of the dose set and delivered. Related medication delivery devices and methods are also disclosed.

An example injector includes a rotary knob for selecting a function and setting a dosing quantity for an injection, a button located on an end of the rotary knob for initiating the injection, an electric motor, an encoder for evaluating output rotary motion of the motor, and a processor that converts the dosing quantity into a number of encoder pulses and controls operation of the motor based on the number of encoder pulses when dosage is triggered. The injector also includes a transmission coupled to the electric motor to convert a speed of the motor, a threaded spindle coupled to the transmission that moves linearly based on the output rotary motion of the motor at the speed as converted by the transmission, and a punch connected to an end of the threaded spindle. The linear movement of the spindle causes the punch to release medicament.

An example injector includes a rotary knob for selecting a function and setting a dosing quantity for an injection, a button located on an end of the rotary knob for initiating the injection, an electric motor, an encoder for evaluating output rotary motion of the motor, and a processor that converts the dosing quantity into a number of encoder pulses and controls operation of the motor based on the number of encoder pulses when dosage is triggered. The injector also includes a transmission coupled to the electric motor to convert a speed of the motor, a threaded spindle coupled to the transmission that moves linearly based on the output rotary motion of the motor at the speed as converted by the transmission, and a punch connected to an end of the threaded spindle. The linear movement of the spindle causes the punch to release medicament.

An example injector includes a rotary knob for selecting a function and setting a dosing quantity for an injection, a button located on an end of the rotary knob for initiating the injection, an electric motor, an encoder for evaluating output rotary motion of the motor, and a processor that converts the dosing quantity into a number of encoder pulses and controls operation of the motor based on the number of encoder pulses when dosage is triggered. The injector also includes a transmission coupled to the electric motor to convert a speed of the motor, a threaded spindle coupled to the transmission that moves linearly based on the output rotary motion of the motor at the speed as converted by the transmission, and a punch connected to an end of the threaded spindle. The linear movement of the spindle causes the punch to release medicament.

A drive mechanism for a medication delivery device is presented having a housing, a rotation member that rotates in a first direction with respect to the housing during setting of a dose of a medication and rotates in a second direction with respect to the housing during delivery of the dose, the second direction being opposite to the first direction. The device also has a piston rod that is displaced in a distal direction with respect to the housing for delivering the dose, a drive member which follows rotational movement of the rotation member in the second direction during delivery of the dose, and a stop member which prevents rotational movement of the drive member with respect to the housing in the first direction during setting of the dose.

A dispensing mechanism for administering a dosage of a medicament includes dosage setting means (7) for setting the dosage of a medicament to be administered; expelling means (15) for expelling a medicament from a medicament container; and coupling means (21) operatively coupled with the dosage setting means (7) and the expelling means (15), wherein the coupling means (21) is arranged to convert displacement of the dosage setting means (7) into a displacement of the expelling means (15) in a first direction, wherein the expelling means (15) includes a ratchet means (18a, 18b), and wherein the mechanism includes a first and a second independently moveable resisting pawl (14a, 14b) means facing a common side of the ratchet means (18), the first and the second resisting pawl means (14a, 14b) being configured to engage with the ratchet means (18a, 18b) and resist displacement of the expelling means (15) in a second direction opposite to said first direction.

A syringe having a mechanical ejection mechanism. The ejection mechanism includes an actuator and a rotational gear. The actuator has a retractable pawl configured to engage the gear when the actuator is displaced from a non-depressed position into a depressed position. Displacement of the actuator causes the gear to rotate by a predetermined angle. The rotation of the gear is translated into linear displacement of the plunger within the barrel, thereby ejecting a predetermined amount of solution from the barrel.

Methods, systems, computer-readable media, and apparatuses for facilitating administering of medicine are disclosed.

Method of manufacturing a drug delivery device, comprising the steps of (i) providing a plurality of components which in an assembled state form a processor-controlled drug delivery device, (ii) determining a parameter value for at least one component, (iii) assembling the components to form a drug delivery device, and (iv) storing in the processor memory correction data, the correction data being based on one or more differences between a determined parameter value and a corresponding nominal value.