Patent Description:
Patients suffering from various diseases must frequently inject themselves with medication. To allow a person to conveniently and accurately self-administer medicine, a variety of devices broadly known as pen injectors or injection pens have been developed. Generally, these pens are equipped with a cartridge including a piston and containing a multi-dose quantity of liquid medication. A drive member is movable forward to advance the piston in the cartridge to dispense the contained medication from an outlet at the distal cartridge end, typically through a needle. In disposable or prefilled pens, after a pen has been utilized to exhaust the supply of medication within the cartridge, a user discards the entire pen and begins using a new replacement pen. In reusable pens, after a pen has been utilized to exhaust the supply of medication within the cartridge, the pen is disassembled to allow replacement of the spent cartridge with a fresh cartridge, and then the pen is reassembled for its subsequent use.

Many pen injectors and other medication delivery devices utilize mechanical systems in which members rotate and/or translate relative to one another in a manner proportional to the dose delivered by operation of the device. Systems to measure the relative movement of members of a medication delivery device have been developed in order to assess the dose delivered. Yet, systems integrated into the device or module for high volume manufacturing and repeatable accuracy during the product's lifecycle have been challenging to design. The administration of a proper amount of medication requires that the dose delivered by the medication delivery device be accurate. Many pen injectors and other medication delivery devices do not include the functionality to automatically detect and record the amount of medication delivered by the device during the injection event. In the absence of an automated system, a patient must manually keep track of the amount and time of each injection. Accordingly, there is a need for a device that is operable to automatically detect the dose delivered by the medication delivery device during an injection event, and/or overcome one or more of these and other shortcomings of the prior art.

<CIT> discloses a drug dispensing-tracking device for use in combination with a drug-injection device, where the device comprises a sleeve configured to connect with at least one mechanical feature provided on the injection device, a battery, at least one sensor, an electrical circuit for analog or digital short range communication, and a transmission element. The sensor is configured to automatically detect at least one of an auditory signal, movement, and optical signal, and an auditory signal is generated by at least one of the setting of the injection device for dispensing a drug, the dispensing action of the injection device, and the flow of the drug out of the injection device.

<CIT> discloses a supplemental device for attachment to an injection device having a display; a processor arrangement; a dose dialled detector operable to detect a dose of medicament dialled into an attached injection device; a dose delivery determiner for determining that a dose of medicament has been delivered; a quantity determiner determining a quantity of medicament that has been delivered; and a clock configured to determine a current time.

<CIT> discloses a portable electronic module for releasable coupling to an associated mechanical medication delivery device. The electronic module comprises: means for wirelessly detecting measurable signals generated in response to an event or action occurring within the associated mechanical medication delivery device, and associating with each event or action a time stamp; mutually cooperating coupling means for releasable coupling the electronic module to the associated mechanical medication delivery device; and means for storing information associated with the detected measurable signals, and storing the associated time stamp wherein the measurable signals are acoustical and/or vibrational signals.

<CIT> discloses a button-activated medicament delivery device (<NUM>) comprising a housing arranged to house a medicament container, a vibration sensor configured to measure vibrations induced by the button-activated medicament delivery device during a medicament delivery, a button arranged to initiate medicament delivery from the medicament container, and to activate the vibration sensor when initiating the medicament delivery, and processing circuitry configured to obtain a vibration measurement from the vibration sensor and to compare the vibration measurement with a reference vibration measurement characteristic for the button-activated medicament delivery device during medicament delivery. The processing circuitry is configured to generate a time of measurement of the vibration measurement in case the vibration measurement matches the reference vibration measurement.

Aspects, embodiments and examples of the present disclosure which do not fall under the scope of the appended claims do not form part of the invention and are merely provided for illustrative purposes.

There is hereinafter disclosed a medication delivery device, including a device body, a dose setting member attached to the device body and rotatable relative to the device body about an axis of rotation during dose delivery. The dose setting member includes a sensed element including surface features radially-spaced from one another about the axis of rotation of the dose setting member. An actuator or a dose button is attached to the device body. The sensed element is rotatable relative to the dose button during dose delivery in relation to the amount of dose delivered. A rotational sensor includes a movable element contactable against the surface features of the sensed element. The dose button may be configured to house the rotational sensor. The movable element is positioned to move over the surface features during rotation of the sensed element relative to the dose button during dose delivery. The rotational sensor is configured to generate a signal in response to the movement of the movable element over the surface features during the rotation of the dose setting member. A controller is operatively coupled to the rotational sensor and may be housed by the dose button or a module. In response to receiving the generated signal from the rotational sensor, the controller is configured to determine a number of the surface features passing the movable element of the rotational sensor during dose delivery.

There is also hereinafter disclosed a medication delivery device, in which an actuator has a first position in which a movable element of a rotational sensor is disengaged from axially extending surface features, and a second position in which the movable element of the rotational sensor is contactable with the axially extending surface features. The actuator may be a dose button. When the actuator is in the second position, a controller is configured, upon receiving a signal indicative of contact with an initial first one of the axially extending surface features, to activate the controller to a full power state, and the controller is configured, upon receiving a signal indicative of contact with a subsequent one of the axially extending surface features after the initial first one, to determine a number of the axially extending surface features passing the movable element of the rotational sensor during dose delivery.

Additional embodiments of the disclosure, as well as features and advantages thereof, will become more apparent by reference to the description herein taken in conjunction with the accompanying drawings. The components in the figures are not necessarily to scale. Moreover, in the figures, like-referenced numerals designate corresponding parts throughout the different views.

The present disclosure relates to sensing systems for medication delivery devices. In one aspect, the sensing system is for sensing of relative rotational movement between a dose setting member and an actuator of the medication delivery device in order to determine the amount of a dose delivered by a medication delivery device. The sensed relative rotational movements are correlated to the amount of the dose delivered. By way of illustration, the medication delivery device is described in the form of a pen injector. However, the medication delivery device may be any device which is used to set and to deliver a dose of a medication, such as pen injectors, infusion pumps and syringes. The medication may be any of a type that may be delivered by such a medication delivery device.

Devices described herein, such as a device <NUM>, <NUM>, <NUM>, <NUM> or <NUM>, may further comprise a medication, such as for example, within a reservoir or cartridge <NUM>. In another embodiment, a system may comprise one or more devices including device <NUM> and a medication. The term "medication" refers to one or more therapeutic agents including but not limited to insulins, insulin analogs such as insulin lispro or insulin glargine, insulin derivatives, GLP-<NUM> receptor agonists such as dulaglutide or liraglutide , glucagon, glucagon analogs, glucagon derivatives, gastric inhibitory polypeptide (GIP), GIP analogs, GIP derivatives, oxyntomodulin analogs, oxyntomodulin derivatives, therapeutic antibodies and any therapeutic agent that is capable of delivery by the above device. The medication as used in the device may be formulated with one or more excipients. The device is operated in a manner generally as described above by a patient, caregiver or healthcare professional to deliver medication to a person.

An exemplary medication delivery device <NUM> is illustrated in <FIG> as a pen injector configured to inject a medication into a patient through a needle. Device <NUM> includes a body <NUM> comprising an elongated, pen-shaped housing <NUM> including a distal portion <NUM> and a proximal portion <NUM>. Distal portion <NUM> is received within a pen cap <NUM>. Referring to <FIG>, distal portion <NUM> contains a reservoir or cartridge <NUM> configured to hold the medicinal fluid to be dispensed through its distal outlet end during a dispensing operation. The outlet end of distal portion <NUM> is equipped with a removable needle assembly <NUM> including an injection needle <NUM> enclosed by a removable cover <NUM>. A piston <NUM> is positioned in reservoir <NUM>. An injecting mechanism positioned in proximal portion <NUM> is operative to advance piston <NUM> toward the outlet of reservoir <NUM> during the dose dispensing operation to force the contained medicine through the needled end. The injecting mechanism includes a drive member <NUM>, illustratively in the form of a screw, axially moveable relative to housing <NUM> to advance piston <NUM> through reservoir <NUM>.

A dose setting member <NUM> is coupled to housing <NUM> for setting a dose amount to be dispensed by device <NUM>. In the illustrated embodiment, dose setting member <NUM> is in the form of a screw element operative to spiral (i.e., simultaneously move axially and rotationally) about a longitudinal axis AA of rotation relative to housing <NUM> during dose setting and dose dispensing. <FIG> illustrate the dose setting member <NUM> fully screwed into housing <NUM> at its home or zero dose position. Dose setting member <NUM> is operative to screw out in a proximal direction from housing <NUM> until it reaches a fully extended position corresponding to a maximum dose deliverable by device <NUM> in a single injection. The extended positon may be any position between a position corresponding to an incremental extended position (such as a dose setting a <NUM> or <NUM> unit) to a fully extended position corresponding to a maximum dose deliverable by device <NUM> in a single injection and to screw into housing <NUM> in a distal direction until it reaches the home or zero position corresponding to a minimum dose deliverable by device <NUM> in a single injection.

Referring to <FIG>, dose setting member <NUM> includes a cylindrical dose dial member <NUM> having a helically threaded outer surface that engages a corresponding threaded inner surface of housing <NUM> to allow dose setting member <NUM> to spiral relative to housing <NUM>. Dose dial member <NUM> further includes a helically threaded inner surface that engages a threaded outer surface of sleeve <NUM> (<FIG>) of device <NUM>. The outer surface of dial member <NUM> includes dose indicator markings, such as numbers that are visible through a dosage window <NUM> to indicate to the user the set dose amount. Dose setting member <NUM> further includes a tubular flange <NUM> that is coupled in the open proximal end of dial member <NUM> and is axially and rotationally locked to dose dial member <NUM> by detents <NUM> received within openings <NUM> in dial member <NUM>. In one example, dose setting member <NUM> further includes an optional collar or skirt <NUM> positioned around the outer periphery of dial member <NUM> at its proximal end. Skirt <NUM> is axially and rotationally locked to dial member <NUM> by tabs <NUM> received in slots <NUM>.

Dose setting member <NUM> therefore may be considered to comprise any or all of dose dial member <NUM>, flange <NUM>, and skirt <NUM>, as they are all rotationally and axially fixed together. Dose dial member <NUM> is directly involved in setting the dose and driving delivery of the medication. Flange <NUM> is attached to dial member <NUM> and, as described later, cooperates with a clutch to selectively couple dial member <NUM> with a dose button. As shown, skirt <NUM> provides a surface external of body <NUM> to enable a user to rotate dose dial member <NUM> for setting a dose.

In the embodiment illustrated in <FIG>, the dose button of the illustrated device <NUM> is one-piece component which combines both skirt <NUM> and the dose button <NUM> of <FIG>. In this embodiment, the flange is attached to the dial member and cooperates with a clutch, described below, to selectively couple the dial member with the one-piece dose button, shown as button <NUM>. The radial exterior surface of one-piece dose button <NUM> provides a surface external of the device body <NUM> to rotate the dial member.

Skirt <NUM> illustratively includes a plurality of surface contours <NUM> and an annular ridge <NUM> formed on the outer surface of skirt <NUM>. Surface contours <NUM> are illustratively longitudinally extending ribs and grooves that are circumferentially spaced around the outer surface of skirt <NUM> and facilitate a user's grasping and rotating the skirt. In an alternative embodiment, skirt <NUM> is removed or is integral with dial member <NUM>, and a user may grasp and rotate dose dial member <NUM> for dose setting.

Delivery device <NUM> includes an actuator <NUM> having a clutch <NUM> which is received within dose dial member <NUM>. Clutch <NUM> includes an axially extending stem <NUM> at its proximal end. Actuator <NUM> further includes dose button <NUM> positioned proximally of skirt <NUM> of dose setting member <NUM>, as shown. Dose button <NUM> includes a mounting collar <NUM> (<FIG>) centrally located on the distal surface of dose button <NUM>. Collar <NUM> is attached to stem <NUM> of clutch <NUM>, such as with an interference fit or an ultrasonic weld, so as to axially and rotatably fix together dose button <NUM> and clutch <NUM>.

Dose button <NUM> includes a disk-shaped proximal end surface or face <NUM> and an annular wall portion <NUM> extending distally and spaced radially inwardly of the outer peripheral edge of face <NUM> to form an annular lip <NUM> there between. Face <NUM> of dose button <NUM> serves as a push surface against which a force can be applied manually, i.e., directly by the user to push actuator <NUM> in a distal direction. Dose button <NUM> illustratively includes a recessed portion <NUM> centrally located on proximal face <NUM>, although proximal face <NUM> alternatively may be a flat surface. A bias member <NUM>, illustratively a spring, is disposed between the distal surface <NUM> of button <NUM> and a proximal surface <NUM> of tubular flange <NUM> to urge actuator <NUM> and dose setting member <NUM> axially away from each other. Dose button <NUM> is depressible by a user to initiate the dose dispensing operation. In an alternative embodiment, skirt <NUM> is omitted from the device, and the annular wall portion <NUM> of dose button <NUM> extends distally to a location approximately to the distal extent of the skirt relative to the dial member as shown in the figures.

Delivery device <NUM> is operable in both a dose setting mode and a dose dispensing mode. In the dose setting mode of operation, dose setting member <NUM> is dialed (rotated) relative to housing <NUM> to set a desired dose to be delivered by device <NUM>. Dialing in the proximal direction serves to increase the set dose, and dialing in the distal direction serves to decrease the set dose. Dose setting member <NUM> is adjustable in rotational increments (e.g., clicks) corresponding to the minimum incremental increase or decrease of the set dose during the dose setting operation. For example, one increment or "click" may equal one-half or one unit of medication. The set dose amount is visible to the user via the dial indicator markings shown through dosage window <NUM>. Actuator <NUM>, including dose button <NUM> and clutch <NUM>, move axially and rotationally with dose setting member <NUM> during the dialing in the dose setting mode.

Dose dial member <NUM>, flange <NUM> and skirt <NUM> (when employed) are all fixed rotationally to one another, and rotate and extend proximally of the medication delivery device <NUM> during dose setting, due to the threaded connection of dose dial member <NUM> with housing <NUM>. During this dose setting motion, dose button <NUM> is rotationally fixed relative to skirt <NUM> by complementary splines <NUM> of flange <NUM> and clutch <NUM> (<FIG>), which are urged together by bias member <NUM>. In the course of dose setting, skirt <NUM> and dose button <NUM> move relative to housing <NUM> in a spiral manner from a "start" position to an "end" position. This rotation relative to the housing is in proportion to the amount of dose set by operation of the medication delivery device <NUM>.

Once the desired dose is set, device <NUM> is manipulated so the injection needle <NUM> properly penetrates, for example, a user's skin. The dose dispensing mode of operation is initiated in response to an axial distal force applied to the proximal face <NUM> of dose button <NUM>. The axial force is applied by the user directly to dose button <NUM>. This causes axial movement of actuator <NUM> in the distal direction relative to housing <NUM>.

The axial shifting motion of actuator <NUM> compresses biasing member <NUM> and reduces or closes the gap between dose button <NUM> and tubular flange <NUM>. This relative axial movement separates the complementary splines <NUM> on clutch <NUM> and flange <NUM>, and thereby disengages actuator <NUM>, e.g., dose button <NUM>, from being rotationally fixed to dose setting member <NUM>. In particular, dose setting member <NUM> is rotationally uncoupled from actuator <NUM> to allow backdriving rotation of dose setting member <NUM> relative to actuator <NUM> and housing <NUM>. Also, since dose setting member <NUM> and actuator <NUM> are free to relatively rotate, actuator <NUM> is held from rotating relative to device housing <NUM> by the user's engagement of dose button <NUM> by pressing against it.

As actuator <NUM> is continued to be axially plunged without rotation relative to housing <NUM>, dial member <NUM> screws back into housing <NUM> as it spins relative to dose button <NUM>. The dose markings that indicate the amount still remaining to be injected are visible through window <NUM>. As dose setting member <NUM> screws down distally, drive member <NUM> is advanced distally to push piston <NUM> through reservoir <NUM> and expel medication through needle <NUM> (<FIG>).

During the dose dispensing operation, the amount of medicine expelled from the medication delivery device is proportional to the amount of rotational movement of the dose setting member <NUM> relative to actuator <NUM> as the dial member <NUM> screws back into housing <NUM>. The injection is completed when the internal threading of dial member <NUM> has reached the distal end of the corresponding outer threading of sleeve <NUM> (<FIG>). Device <NUM> is then once again arranged in a ready state or zero dose position as shown in <FIG> and <FIG>.

The dose delivered may be derived based on the rotation of dose setting member <NUM> relative to actuator <NUM> during dose delivery. This rotation may be determined by detecting the incremental movements of the dose setting member which are "counted" as the dose setting member is rotated during dose delivery.

Further details of the design and operation of an exemplary delivery device <NUM> may be found in <CIT>, entitled Medication Dispensing Apparatus with Triple Screw Threads for Mechanical Advantage. Another example of the delivery device is an auto-injector device that may be found in <CIT>, entitled "Automatic Injection Device With Delay Mechanism Including Dual Functioning Biasing Member," where such device being modified with one or more various sensor systems described herein to determine an amount of medication delivered from the medication delivery device based on the sensing of relative rotation within the medication delivery device. Another example of the delivery device is a reusable pen device that may be found in <CIT>, entitled "Medication Injector Apparatus with Drive Assembly that Facilitates Reset," where such device being modified with one or more various sensor systems described herein to determine an amount of medication delivered from the medication delivery device based on the sensing of relative rotation within the medication delivery device.

The dose detection systems use a sensing component and a sensed component attached to members of the medication delivery device. The term "attached" encompasses any manner of securing the position of a component to another component or to a member of the medication delivery device such that they are operable as described herein. For example, a sensing component may be attached to a member of the medication delivery device by being directly positioned on, received within, integral with, or otherwise connected to, the member. Connections may include, for example, connections formed by frictional engagement, splines, a snap or press fit, sonic welding or adhesive.

The term "directly attached" is used to describe an attachment in which two components, or a component and a member, are physically secured together with no intermediate member, other than attachment components. An attachment component may comprise a fastener, adapter or other part of a fastening system, such as a compressible membrane interposed between the two components to facilitate the attachment. A "direct attachment" is distinguished from attachment where the components/members are coupled by one or more intermediate functional members, such as the way dose dial member <NUM> is coupled in <FIG> to dose button <NUM> by clutch <NUM>.

The term "fixed" is used to denote that an indicated movement either can or cannot occur. For example, a first member is "fixed rotationally" with a second member if the two members are required to move together in rotation. In one aspect, a member may be "fixed" relative to another member functionally, rather than structurally. For example, a member may be pressed against another member such that the frictional engagement between the two members fixes them together rotationally, while the two members may not be fixed together absent the pressing of the first member.

Various sensor systems are contemplated herein. In general, the sensor systems comprise a sensing component and a sensed component. The term "sensing component" refers to any component which is able to detect the relative position or movement of the sensed component. The sensing component includes a sensing element, or "sensor", along with associated electrical components to operate the sensing element. The "sensed component" is any component for which the sensing component is able to detect the position and/or movement of the sensed component relative to the sensing component. For the dose detection system, the sensed component rotates relative to the sensing component, which is able to detect the rotational movement of the sensed component. The sensing component may comprise one or more sensing elements, and the sensed component may comprise one or more sensed elements. The sensor system detects the movement of the sensed component and provides outputs representative of the movement of the sensed component.

Illustratively, the dose detection system includes an electronics assembly suitable for operation of the sensor system as described herein. A controller is operably connected to the sensor system to receive outputs from the rotational sensor. The controller begins receiving generated signals from the rotational sensor indicative of counts from first to last one for a total number of counts that is used for determining total angular displacement. The controller may be configured to receive data indicative of the angular movement of the dose setting member that can be used to determine from the outputs the amount of dose delivered by operation of the medication delivery device. The controller may be configured to determine from the outputs the amount of dose delivered by operation of the medication delivery device. The controller may include conventional components such as a processor, power supply, memory, microcontrollers, etc. Alternatively, at least some components may be provided separately, such as by means of a computer, smart phone or other device. Means are then provided to operably connect the external controller components with the sensor system at appropriate times, such as by a wired or wireless connection.

An exemplary electronics assembly <NUM> is shown in <FIG> and can include a flexible printed circuit board (FPCB) having a plurality of electronic components. The electronics assembly comprises a sensor system including one or more sensors operatively communicating with a processor for receiving signals from the sensor representative of the sensed rotation. Ccircuit board of electronics assembly <NUM> further includes a microcontroller unit (MCU) as the controller comprising at least one processing core and internal memory. The system includes a battery, illustratively a coin cell battery, for powering the components. The controller of electronics assembly <NUM> includes control logic operative to perform the operations described herein, including detecting the angular movement of the dose setting components during dose setting and/or dose delivery and/or detecting a dose delivered by medication delivery device <NUM> based on a detected rotation of the dose setting member relative to the actuator. Many of the components of the electronics assembly may be contained in a compartment <NUM> located proximal of the dose button <NUM>.

The controller of electronics assembly <NUM> is operative to store the total angular movement used for determining dose delivery and/or the detected dose delivery in local memory (e.g., internal flash memory or on-board EEPROM). The controller is further operative to wirelessly transmit a signal representative of the total counts, total angular movement, and/or detected dose to a paired remote electronic device, such as a user's smartphone. Transmission may, for example, be over a Bluetooth low energy (BLE) or other suitable short or long range wireless communication protocol. Illustratively, the BLE control logic and controller are integrated on the same circuit.

The dose detection system involves detecting relative rotational movement between two members. With the extent of rotation having a known relationship to the amount of a delivered dose, the sensor system operates to detect the amount of angular movement from the start of a dose injection to the end of the dose injection. For example, a typical relationship for a pen injector is that an angular displacement of a dose setting member of <NUM>° is the equivalent of one unit of dose, although other angular relationships are also suitable, such as, for example, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> degrees may be used for a unit or <NUM> unit. The sensor system is operable to determine the total angular displacement of a dose setting member during dose delivery. Thus, if the angular displacement is <NUM>°, then <NUM> units of dose have been delivered.

The angular displacement is determined by counting increments of dose amounts as the injection proceeds. For example, a sensing system may use a repeating pattern of a sensed element, such that each repetition is an indication of a predetermined degree of angular rotation. Conveniently, the pattern may be established such that each repetition corresponds to the minimum increment of dose that can be set with the medication delivery device.

The sensor system components may be permanently or removably attached to the medication delivery device. In an illustrative embodiment, as least some of the dose detection system components are provided in the form of a module that is removably attached to the medication delivery device. This has the advantage of making these sensor components available for use on more than one pen injector.

The sensor system detects during dose delivery the relative rotation of the sensed component, and therefore of the dose setting member, from which is determined the amount of a dose delivered by the medication delivery device. In an illustrative embodiment, a rotational sensor is attached, and rotationally fixed, to the actuator. The actuator does not rotate relative to the body of the medication delivery device during dose delivery. In this embodiment, a sensed component is attached, and rotationally fixed, to the dose setting member, which rotates relative to the actuator and the device body during dose delivery. In some of the embodiments described herein, the sensed component includes a ring structure having a plurality of proximally extending projections circumferentially disposed relative to one another. Projections are shaped and sized to deflect a movable element of the rotational sensor. Embodiments described herein may be provided for a module that is removably attachable to the dose button of the delivery device or integrated within the dose button of the delivery device, with an embodiment illustrated in <FIG>.

Referring to <FIG>, there is shown in diagrammatic form a dose delivery detection system <NUM> including a module <NUM> useful in combination with a medication delivery device, such as device <NUM>. Module <NUM> carries a sensor system, shown generally at <NUM>, including a rotational sensor <NUM> and other associated components such as a processor, memory, battery, etc. Module <NUM> is provided as a separate component which may be removably attached to the actuator.

Dose detection module <NUM> includes a body <NUM> attached to dose button <NUM>. Body <NUM> illustratively includes a cylindrical side wall <NUM> and a top wall <NUM>, spanning over and sealing side wall <NUM>. By way of example, in <FIG> side wall <NUM> is diagrammatically shown having inwardly-extending tabs <NUM> attaching module <NUM> to dose button <NUM>. Module <NUM> is thereby attached to dose button <NUM> such that pressing on the module delivers a set dose.

Dose detection module <NUM> may alternatively be attached to dose button <NUM> via any suitable fastening means, such as a snap or press fit, threaded interface, etc., provided that in one aspect module <NUM> may be removed from a first medication delivery device and thereafter attached to a second medication delivery device. The attachment may be at any location on dose button <NUM>, provided that dose button <NUM> is able to move any required amount axially relative to dose setting member <NUM>, as discussed herein.

During dose delivery, dose setting member <NUM> is free to rotate relative to dose button <NUM> and module <NUM>. In the illustrative embodiment, module <NUM> is rotationally fixed with dose button <NUM> and does not rotate during dose delivery. This may be provided structurally, such as with tabs <NUM> of <FIG>, or by having mutually-facing splines or other surface features on the module body <NUM> and dose button <NUM> engage upon axial movement of module <NUM> relative to dose button <NUM>. In another embodiment, the distal pressing of the module provides a sufficient frictional engagement between module <NUM> and dose button <NUM> as to functionally cause the module <NUM> and dose button <NUM> to remain rotationally fixed together during dose delivery.

Top wall <NUM> is spaced apart from face <NUM> of dose button <NUM> and thereby provides a compartment <NUM> containing some or all of electronics assembly <NUM>. Compartment <NUM> defines a chamber <NUM> and may be open at the bottom, or may be enclosed, such as by a bottom wall <NUM>. Bottom wall <NUM> may be positioned to bear directly against face <NUM> of dose button <NUM>. Alternatively, bottom wall <NUM> if present may be spaced apart from dose button <NUM> and other contacts between module <NUM> and dose button <NUM> may be used such that an axial force applied to module <NUM> is transferred to dose button <NUM>.

Further disclosed herein is a dose detection system operable to determine the amount of dose delivered based on relative rotation between a dose setting member and the device body. The dose detection system utilizes a dose setting member attached to the device body and rotatable relative to the device body about an axis of rotation during dose delivery. A sensed element is attached to and rotationally fixed with the dose setting member. An actuator is attached to the device body and is held against rotation relative to the device body during dose delivery. The sensed element thereby rotates relative to the actuator during dose delivery in relation to the amount of dose delivered.

The dose detection system comprises a sensor system including a rotational sensor attached to the actuator. The sensed element includes surface features radially-spaced about the axis of rotation of the dose setting member. The surface features may be arranged to correlate to the equivalent of one unit of dose, although other angular relationships are also suitable, such as, for example, <NUM>, <NUM>, <NUM>, <NUM>, <NUM>, <NUM> or <NUM> degrees may be used for a unit or <NUM> unit. The rotational sensor includes a movable element attached to the actuator and having a contact portion capable of resting against and spring-biased in the direction of the surface features of the sensed element. The contact surface is thereby positioned to move over the surface features during rotation of the sensed element relative to the actuator during dose delivery. The rotational sensor is responsive to the movement of the contact portion over the surface features and generates signals corresponding to the rotation of the dose setting member. A controller is responsive to the signals generated by the rotational sensor to determine a dose count for determining the amount of dose delivery based on the detected rotation of the dose setting member relative to the actuator during dose delivery.

The contact surface is biased against the physical features to ensure proper contact between the contact surface and the physical features during rotation. In one embodiment, the movable element is a resilient member having one portion attached to the actuator at a location displaced from the contact surface. In one example, the movable element is a following member comprising a beam attached at one end to the actuator and having the contact surface at the other end. The beam is flexed to urge the contact surface in the direction of the surface features. Alternatively, the movable element may be biased in any of a variety of other ways. In addition to the use of a resilient beam, the biasing may be provided, for example, by use of a spring component. Such spring component may for example comprise a compression, tension, or torsion coil spring. In yet other embodiments, the movable element may be biased against the surface features of the sensed element by a separate resilient member or spring component bearing against the movable element.

In one embodiment, the surface features are uniform elements which are spaced intermittently around the axis of rotation of the sensed element. In a particular aspect, the surface features are equi-radially spaced projections separated by intervening recesses. The contact surface of the movable element is positioned to ride over the projections, and to move inwardly relative to the intervening recesses. The movable element may, for example, be a resilient beam which flexes outwardly along the projections, or a translating member which rides up over the projections.

In one aspect, the projections are ramped upward in the direction opposite to rotation of the sensed element during dose delivery to facilitate movement of the contact surface along and over the projections. In another aspect, the projections are provided with differing profiles in opposed angular directions to provide for detecting the direction of rotation of the sensed element relative to the actuator. The projections may extend in any direction detectable by the movable element. For example, the projections may extend axially or radially. Axial projections may extend proximally or distally. Radial projections may extend inwardly or outwardly.

The sensed element is attached to the dose setting member. Depending on the medication delivery device, the sensed element may be attached to the skirt, the flange or the dose dial, or any other component that rotates relative to the device body during dose delivery in relation to the amount of dose delivered.

In one aspect, the sensing system of dose detection system <NUM> is originally incorporated into a medication delivery device as an integrated system. In another aspect, there is disclosed a modular form of the dose detection system. The use of a removably attached module is particularly adapted to use with a medication delivery device in which the actuator and/or the dose setting member include portions external to the medication device housing. These external portions allow for direct attachment of the module to the actuator, such as a dose button, and/or attachment of a sensed element to a dose setting member, such as a skirt, flange, or dose dial member, as described herein. Alternately, the sensed element is integral with the medication delivery device and the module is removably attached. This has the advantage that the more complex and expensive electronics, including the rotational sensor and controller, may be reused with different medication deliver devices. By comparison, the sensed element may use relatively simple features, for example radially-spaced projections, which do not add significantly to the cost of the medication delivery device.

An exemplary medication delivery device incorporating an exemplary dose detection system is shown in <FIG>. The device includes a sensor system which detects surface features of a sensed element extending from one or more of the components of dose setting device <NUM>, such as the dose dial member <NUM> and/or flange <NUM>. In particular, sensor system <NUM> of dose detection system <NUM> includes the rotational sensor <NUM> and a sensed element <NUM> having surface features. Examples of the location and arrangement of the surface features are shown in illustrative examples: axial surface features of the flange (for example, <FIG>), axial surface features of the dose dial member (for example, <FIG>), outer radial surface features of the dose dial member (for example, <FIG>), and inner radial surface feature of the flange (for example, <FIG>).

In one example, shown in <FIG>, sensed element <NUM> includes a ring <NUM> coupled to flange <NUM>. It will be appreciated that ring <NUM> may be permanently affixed to flange <NUM> (shown) or dose dial member <NUM> with an adhesives and/or fasteners, or it may be configured to be removably attached to flange <NUM> or dose dial member, such as, for example, with a mechanical fastener or a carrier component. The ring may be omitted and the surface features may be integrally formed from flange <NUM> or dose dial member <NUM> as a unitary member (shown for example in <FIG> or <FIG>), such as, for example, through molding or additive manufacturing.

As shown in <FIG> and <FIG>, surface features <NUM> comprising a series of ramp-like projections <NUM>. Rotational sensor <NUM> includes one or more movable elements <NUM> (<FIG>), in this instance comprising a following member pin <NUM> which is received through a button aperture <NUM> defined by the face <NUM> of dose button <NUM> and is positioned to have a distal contact surface <NUM> that is capable of resting against surface features shown as projections <NUM> as flange <NUM> rotates relative to dose button <NUM>. Pin <NUM> is shown extending through a module aperture <NUM> defined by the distal bottom wall <NUM> that is in a coaxial alignment with button aperture <NUM>. The interior surfaces that define the respective module aperture and button aperture may be configured to provide bearing support to the pin along two locations during its axial movement. Such size and arrangement of the apertures <NUM>, <NUM> may enhance linear axial motion of the pin to reduce inconsistent readings from the sensor or switch employed. More than one pin and corresponding apertures defined by their respective component may be utilized for redundant sensing to reduce error readings.

Pin <NUM> may include a pin flange <NUM> received between contact surface <NUM> and dose button <NUM>. Coil spring <NUM> is positioned between pin flange <NUM> and dose button <NUM> and biases pin <NUM> in the distal direction of projections <NUM>. As flange <NUM> rotates during dose delivery, the pin(s) and dose button maintain their relative position, and contact surface <NUM> of pin <NUM> rides up over each surface feature shown as projection <NUM> against the biasing force of coil spring <NUM>. Pin <NUM> then drops down into each recess <NUM> between adjacent projections. Pin <NUM> thereby operates as a following member which follows the contours of the projections and recesses.

Rotational sensor <NUM> further includes a sensing element <NUM> positioned to detect movement of pin <NUM> as it rides over projections <NUM> and falls into intervening recesses <NUM>. The sensing element <NUM> may be provided in various forms operable to detect translational movement of pin <NUM>. By way of example, the sensing element <NUM> is shown in <FIG> as comprising a microswitch that is operated to detect axial movement of pin <NUM> in the proximal direction each time pin <NUM> rides over a projection <NUM>. This activation will result in successive on-off or off-on setting changes for the microswitch for each passage of a projection/recess pair of ring <NUM>.

In the manner previously described, rotational sensor <NUM> detects angular movement of the dose setting member by counting the number of projections that trigger sensing element <NUM> during dose delivery. Rotational sensor <NUM> generates signals indicating this angular movement and those signals are used by the controller to determine the total rotation of the dose setting member during dose delivery that can be used to determine the amount of the dose delivery. In one example, the rotational sensor <NUM> generates signals indicative of a count number and the controller receives the generated signal. Controller may store the number of counts to an internal memory and/or transmit electronically the number of counts to an external device. Controller may compare the number of counts to an internal database that correlates the number of counts to a total angular movement and thus a dose delivered. The determined angular movement and/or dose delivered may be displayed on a local display or indicator system (such as numbers) as part of the electronics assembly and/or transmitted electronically to an external device.

<FIG> shows alternative dose detection systems which similarly use radially-spaced projections <NUM> and movable members <NUM> which comprise pins <NUM> which ride along the successive projections and recesses. As shown in <FIG>, each movable member <NUM> includes a contact surface <NUM> which moves over the surface features <NUM> radially-spaced about the axis of rotation, e.g., projections <NUM>. The contact surface <NUM> of pin <NUM> is shown in <FIG> as including an enlarged end portion <NUM> which may desirably be made of a durable, low-friction material which allows pin <NUM> to slide easily across projections <NUM>. The enlarged end portion <NUM> having a cross-sectional area larger than the cross-sectional area of the pin. Also as shown in <FIG>, projections <NUM> may be formed with a surface <NUM> which is ramped upward in the direction opposite to the direction of rotation, shown by arrow <NUM>, of the dose setting member. This further facilitates movement of the following member over the projections.

In another aspect, the opposite side of projections <NUM> may be ramped to allow for rotation of the dose setting member in the opposite direction. Further, the two sides of the projections may be provided with different angles of inclination to allow the dose detection system to detect the direction of rotation. On the other hand, the opposite sides of the projections may be angled more steeply to prevent rotation in the other direction.

Described herein is an embodiment in which the actuator is moved distally relative to the device body to transition from a dose setting mode, or an at rest position, to a dose delivery mode. In the proximally displaced condition, the following members may be separated from the proj ections as one way to allow for rotation of the sensed element relative to the actuator in the direction opposite from dose delivery. However, as also described, in certain embodiments the actuator is rotationally fixed to the dose setting member during dose setting.

In <FIG> there is shown a dose detection system which operates by detecting vibrations associated with rotation of the sensed element relative to the actuator during dose delivery. As sensed element <NUM> rotates in direction <NUM> relative to movable member <NUM>, contact surface <NUM> forces pin <NUM> away from the dose setting member and against the biasing member, e.g., spring <NUM>. Once the contact surface <NUM> passes over the top of the projection, the biasing member forces the following member quickly down into the subsequent recess <NUM>. Referring to <FIG>, with additional movement of sensed element <NUM> in the direction <NUM>, spring <NUM> will drive pin <NUM> down into recess <NUM>, where it will be stopped abruptly by contact with the bottom of the following recess <NUM>. This abrupt stop will be accompanied by a vibration which is detected by the rotational sensor.

For example, in <FIG> there is shown a support <NUM> attached to the proximal end of pin <NUM> and carrying a rotation accelerometer <NUM>. Rotation accelerometer <NUM> is provided primarily to detect vibrations indicative of rotation of the sensed element. In operation of the system, accelerometer <NUM> detects each vibration associated with the passage of pin <NUM> over the top of a projection and falling into the following recess. Accelerometer <NUM> may be of any type capable of detecting the vibration, and in a particular aspect comprises a <NUM>-axes accelerometer. As used herein, this accelerometer is referred to as a "rotation accelerometer" to distinguish it as an accelerometer used in detecting rotation of the sensed element, rather than to suggest a particular type of accelerometer. Other sensors capable of detecting the rotation vibrations may also be used.

Also shown in <FIG> are optional sensor components including a second support <NUM> and a second accelerometer <NUM> that are useful in conjunction with rotation accelerometer <NUM>. As used herein, the second accelerometer is referred to as a "background accelerometer" to distinguish it as an accelerometer used in detecting background vibrations, rather than to suggest a particular type of accelerometer. Background accelerometer <NUM> is provided primarily to detect background vibrations, such as caused by movement of the entire medication delivery device, which vibrations are not indicative of rotation of the sensed element. For this purpose, background accelerometer <NUM> is relatively isolated from pin <NUM>, such as by pin <NUM> being slidingly received within an aperture in dose button <NUM>.

Significant axial movement of pin <NUM> relative to dose button <NUM> will be sensed more strongly by rotation accelerometer <NUM> than by background accelerometer <NUM>. If a vibration sensed by the rotation accelerometer is substantially the same as that sensed by the background accelerometer, then rotation of the sensed element will not be indicated. By comparison, if the amount of vibration detected by the rotation accelerometer is substantially greater than that detected by the background accelerometer at a given time, then rotation of the sensed element is indicated. The controller compares detected rotation vibrations and background vibrations to identify vibrations indicative of rotation of the sensed element relative to the actuator during dose delivery.

The action of the following member during rotation of the sensed element may also be associated with related sounds. In particular, a distinctive sound will be made by the impact of pin <NUM> against the bottom of recess <NUM>. An alternative dose detection system utilizes this sound to detect rotation of sensed element <NUM> relative to dose button <NUM>. By way of example, also shown in <FIG> is a microphone <NUM> forming a component of an alternative sensing system. Upon detecting a sound predetermined to be an indicator of rotation of the sensed element, the rotational sensor generates a signal identifying rotation of the sensed element associated with dose delivery. An additional background sound microphone may be used in order to be able to distinguish rotation sounds from other sounds.

As shown in <FIG>, the following member may be biased, for example, by a coil spring. Alternatively, the following member may be biased against the surface features in various other ways. For example, a resilient member may be used to bias pin <NUM> against projections <NUM>. As shown in <FIG>, resilient member <NUM> is attached at one end to the underside <NUM> of dose button <NUM>. Resilient member <NUM> includes a portion <NUM> at the opposite end resting against the enlarged end portion of the contact surface <NUM> of pin <NUM>. Movement of contact surface <NUM> over the projections causes the pin to translate upwardly against the downward of resilient member <NUM>, and contact surface <NUM> is thereby maintained in position against the surface features. Illustratively, in lieu of pin <NUM>, the following member may comprise resilient member <NUM> and the contact surface may be positioned on end portion <NUM>.

Referring now to <FIG>, there is shown a medication delivery device equipped with a sensing system that is described further as being used to determine the amount of a dose set by operation of the device. Such amount is determined based on the sensing of relative rotational movements during dose setting between members of the medication delivery device, where the sensed movements are correlated as applicable to the amount of the dose set. In different embodiments, the sensing system is configured to determine the amount of at least one of the dose set and the dose delivered by operation of the device, or alternatively both the amount of the dose set and the amount of the dose delivered by operation of the device.

<FIG> illustrate the proximal portion of the device, now referenced as <NUM>, with the dose detection sensor system <NUM> disposed within the dose button <NUM>, rather than a module, and including the rotational sensor <NUM>. The device <NUM> includes many of the same components operational for dose setting and dose dispensing as described with reference to the device <NUM>, including at least a portion of the electronic components in the electronics assembly, and such components will have the same corresponding descriptions. Although the device <NUM> is shown as a device within an integrated dose detection sensing system, such sensing system may be incorporated in a module for removable attachment to a dose button.

The dose setting member <NUM> is coupled to the device housing <NUM> for setting a dose amount to be dispensed by device <NUM>. Dose setting member <NUM> is operative to screw out in a proximal direction from housing <NUM> until it reaches a fully extended position corresponding to a maximum dose deliverable by device <NUM> in a single injection. The cylindrical dose dial member <NUM> of dose setting member <NUM> includes the helically threaded outer surface that engages the corresponding threaded inner surface of housing <NUM> to allow dose setting member <NUM> to spiral relative to housing <NUM>. Dose dial member <NUM> includes the helically threaded inner surface that engages the threaded outer surface of the sleeve of the device <NUM>, such as sleeve <NUM> in <FIG>. The outer surface of dial member <NUM> includes dose indicator markings that are visible through the dosage window <NUM> to indicate to the user the set dose amount. Tubular flange <NUM> of dose setting member <NUM> is coupled in the open proximal end of dial member <NUM> and is axially and rotationally locked to dose dial member <NUM> by detents received within openings in dial member <NUM>, such as, for example, shown in <FIG>.

The actuator <NUM> of delivery device <NUM> includes the clutch <NUM> that is received within dose dial member <NUM>. The proximal end of the clutch <NUM> includes the stem <NUM> that is axially extending from its proximal end. Dose button <NUM> of actuator <NUM> is positioned proximally of dose setting member <NUM>, as shown. The mounting collar <NUM> of dose button <NUM> is attached to stem <NUM> of clutch <NUM>, such as with an interference fit or an ultrasonic weld, so as to axially and rotatably fix together dose button <NUM> and clutch <NUM>. The bias member <NUM>, illustratively a spring, is disposed between the distal surface of mounting collar <NUM> of the dose buttong and the proximal surface of tubular flange <NUM> of the dose setting member to urge actuator <NUM> and dose setting member <NUM> axially away from each other. Dose button <NUM> is depressible by a user to initiate the dose dispensing operation. Bias member <NUM> biases the dose button <NUM> in the proximal first position (as shown in <FIG>) where it stays during dose setting operation, until the user applies an axial force great enough to overcome the biasing force of member <NUM> to move the dose button <NUM> to the distal second position (as shown in <FIG>) for dose dispensing operation.

Dose button <NUM> includes an upper proximal wall <NUM> with the disk-shaped proximal end surface <NUM> and the annular wall portion <NUM> extending distally from the proximal wall <NUM> to define a button housing cavity <NUM>. Surface <NUM> of dose button <NUM> serves as the push surface against which a force can be applied manually, i.e., directly by the user to push actuator <NUM> in a distal direction. Dose button <NUM> include a distal wall <NUM> axially spaced from the proximal wall <NUM>. Distal wall <NUM> may at least partially divide the cavity <NUM> into two proximal and distal cavity portions. The mounting collar <NUM> of dose button <NUM> is shown extending distally from an intermediate location of the distal wall <NUM> for attachment with stem <NUM> of clutch <NUM>. In one example, the surface features <NUM> are disposed within the cavity <NUM> radially outside bias member <NUM>. As shown, the rotational sensor and the controller are disposed within the cavity <NUM>.

Distal wall <NUM> may be configured to allow a portion of the sensor system to extend distally beyond the distal wall <NUM>. Distal wall <NUM> may include a discrete opening or may extend partially across the cavity <NUM> from a portion of the annular wall portion <NUM> to stop short of the opposite end of annular wall portion to define an axial aperture <NUM>, as shown in <FIG>. The axial aperture <NUM> may be spaced radially from the axis AA toward the outer end so that the rotational sensor that extends through the aperture <NUM> is placed over the surface features <NUM> that are radially-spaced about the axis AA of rotation. The electronics assembly <NUM> is shown housed within the dose button <NUM>. The circuit board <NUM> includes a plurality of electronic components, and is shown mounted on the proximal face of the distal wall <NUM>. The sensor system <NUM> includes the rotational sensor <NUM> operatively communicating with the processor of the controller of the circuit board for receiving signals from the sensor representative of the sensed rotation. The rotational sensor <NUM> is shown mounted to a distal face of the circuit board. The controller of the electronics assembly <NUM> includes at least one processing core in electric communication with the rotational sensor <NUM> and internal memory. The assembly <NUM> includes a battery B, illustratively a coin cell battery, for powering the electronics components. The controller includes control logic operative to perform the operations described herein, including detecting a dose delivered by the medication delivery device based on a detected rotation of the dose setting member relative to the actuator. Some of the components in the electronics assembly <NUM> are shown as unconnected for illustrative purposes only, and are actually electrically connected to one another, such as by connectors, wires, or conduits, as understood in the art, such as shown by <NUM> in <FIG>, and illustrated in other figures.

Sensor system <NUM> with the rotational sensor <NUM> is configured to detect surface features <NUM> extending from one or more of the components of dose setting device <NUM>, such as the dose dial member <NUM> (as shown) and/or flange <NUM>. For example, with reference to <FIG>, the axial end surface <NUM> of the dose dial member <NUM> of the dose setting device <NUM> in the shape of a ring may define surface features <NUM>, shown as projections <NUM> spaced radially from one another along the axial end surface, projections separated by intervening recesses <NUM>. In the example shown, there are eighteen projections, each spaced twenty degrees apart from adjacent ones.

The dose button <NUM> is movable relative to device housing <NUM> between two positions. In <FIG>, the dose button <NUM> is in the proximal position where the device is in a first operating dose setting mode in which the dose button may be used to set a dose. In <FIG>, the dose button <NUM> is in the distal position where the device is in a second operating dose delivery mode in which the dose button may be used to deliver the dose. In certain embodiments, the dose button <NUM> is rotationally fixed to the dose setting member in the dose setting mode, and dose button <NUM> may be rotated to set a dose. In this position, rotational sensor <NUM> is axially displaced from the surface features <NUM>. In the dose setting mode, the rotational sensor <NUM> may remain inoperable and the electronics assembly may remain powered off or in a low power state.

Upon pressing proximal wall <NUM>, dose button <NUM> advances distally relative to housing <NUM>, compressing spring <NUM>, as shown in <FIG>. Continued pressing of the dose button <NUM> distally results in back driving dose dial <NUM> in a spiral direction relative to housing <NUM>. As a result, the dose dial <NUM> and flange <NUM> is driven to rotate by the axially moving dose button. The dose detection system may only be operable for counting when the dose button is being pressed. The electronics assembly may include a clock or timer to determine the time elapsed between counts caused by trigger of the rotational sensor from the surface features of the sensed element. When trigger arm is not activated, that is, no counts detected by the controller, for a period of time, this may be used to indicate that the dose is completed.

Upon the sensing of the initial one of surface features <NUM>, the controller is configured to allow wake-up or activation of the electronics assembly <NUM> to a greater or full power state. Triggering of wake-up feature is configured to allow power transmission from the power source (shown as battery) for powering up the electronic components for dose sensing in order to minimize inadvertent power loss or usage when a dose dispensing event is not occurring. In other embodiments, a separate wake-up switch may be provided and arranged within the dose button housing and triggered when the dose button <NUM> is in its distal position. In this instance, the wake-up switch may be located, for example, along the upper end of the flange. After activation of the electronics assembly, the controller begins receiving generated signals from the rotational sensor indicative of counts from first to last one for a total number of counts that is used for determining total angular displacement and thus the amount of dose delivered.

<FIG> depict one example of the rotational sensor <NUM> provided in the device <NUM>. For example, the rotational sensor <NUM> includes a sensor body <NUM> and a movable element comprising a pair of contacts <NUM>, <NUM>. The contacts <NUM>, <NUM> may be resilient, that is having a natural configuration in one state, and capable of being moved or deflected to another state when under a force and returning to the natural configuration when the force is removed. The sensor body <NUM> is shown mounted to the circuit board <NUM> and is operably coupled to the controller of electronics assembly, and is configured to transmit a sensor signal of an electronic characteristic (voltage, resistance, current signal) defined by the contacting or separation of the contacts <NUM>, <NUM> to the controller. The contacts <NUM>, <NUM> may remain spaced apart in a natural state until brought together in contact with one another in an operational state by deflection of at least one of the contacts (shown as contact <NUM>) during engagement with the surface features <NUM>. Alternatively, both of contacts <NUM>, <NUM> may be configured to deflect upon engagement with surface features and contact one another due to the deflection. After engagement of contact <NUM> with the surface feature <NUM>, the contact <NUM> may return to the natural state where it is in spaced relationship with contact <NUM>. Alternatively, the contacts <NUM>, <NUM> may remain contacting each other in a natural state and configured to separate from a contacting relationship due to engagement with the surface features <NUM>, and return to the natural state in their contacting relationship after the passage of the surface feature. According to <FIG>, the rotational sensor <NUM> is in the proximal position as the dose button <NUM> is in its proximal position where the device is in its first operating dose setting mode. According <FIG>, the rotational sensor <NUM> is in the distal position as the dose button <NUM> is in its distal position where the device is in its second operating dose delivery mode.

<FIG> illustrate an example configuration of the contacts <NUM>, <NUM>, although other configurations of the contacts may be utilized. The first contact <NUM> is shown extending axially from the sensor body <NUM>. The first contact <NUM> includes a first segment <NUM> coupled to the sensor body <NUM> and a second segment <NUM> extending from the first segment <NUM>. The first segment <NUM> is shown extending axially from the sensor body <NUM>, and the second segment <NUM> is shown extending radially from the first segment <NUM> at an elbow connection. The second contact <NUM> includes a first segment <NUM> coupled to the sensor body <NUM> and a second segment <NUM> extending from the first segment <NUM>. The first segment <NUM> is shown extending axially from the sensor body <NUM>. The second segment <NUM> is shown extending generally radially from the first segment <NUM> at an elbow connection. The second segment <NUM> includes an arm portion <NUM>, a transition engagement portion <NUM>, and a tip contact portion <NUM> coupled in sequence from the first segment <NUM>. The arm portion <NUM> is sized and shaped to place the tip contact portion <NUM> underneath the second segment <NUM> of the first contact. The arm portion <NUM> is shown extending at an incline in the axial and radial directions from the first segment <NUM>. The transition engagement portion <NUM> is configured to engage directly the surface feature <NUM>. The transition engagement portion <NUM> may have a U-shape, V-shape, or ramped shape to transition the second segment <NUM> from the distal direction to the proximal direction. The tip contact portion <NUM> extends in the radial direction and may be generally in parallel and spaced apart with respect to the second segment <NUM> of the first contact <NUM> in the natural state. The shape of the transition engagement portion <NUM> may allow for sliding contact along the surface features <NUM> without causing jamming of the rotating dose dial member. The depth of the shape of the transition engagement portion <NUM> is sized such that upon its distal surface engaging the surface features <NUM>, the second contact <NUM> deflects in the proximal direction at the elbow with the first segment to place the proximal surface of the tip contact portion <NUM> in contact with the distal surface of the second segment <NUM> of the first contact <NUM>. Such contact is sufficient to generate a sensor signal of an electronic characteristic. Alternatively, one of the contacts may be employed, such as contact <NUM> and the surface features may have an electrical conductive property, such as being coated with a metallic material, such that upon engagement between the contact and the surface feature the rotational sensor can generate a signal, as described herein.

<FIG> depict the proximal portion of the device, now referenced as <NUM>. The device <NUM> includes many of the same components operational for dose setting and dose dispensing as described with reference to the device <NUM> or <NUM>, including at least a portion of the electronic components in the electronics assembly for the dose detection system, and such components will have the same corresponding descriptions. Although the device <NUM> is shown as a device within an integrated sensing system, such sensing system may be incorporated in a module for removable attachment to a dose button. The device <NUM> may have the same device components as device <NUM>, such as, for example, device housing <NUM>, dose dial member <NUM>, flange <NUM>, and electronics assembly <NUM>, except with respect to a different rotational sensor configuration and a different dose setting member with the surface features used for sensing, as will be described. As shown, the rotational sensor and the controller are disposed within the cavity of the button.

Another example of the rotational sensor, referenced generally as <NUM>, of the dose detection sensor system <NUM> that can be used with any module and/or device described herein. For example, the rotational sensor <NUM> is a microswitch including a sensor body <NUM> and a movable element comprising a trigger arm <NUM>. With reference to the previous figures, the dose button housing is configured to include the axial aperture spaced radially from the axis AA toward the outer end in order for trigger arm <NUM> of the rotational sensor <NUM> to extend through for placement over the surface features <NUM> that are radially-spaced about the axis AA of rotation. The trigger arm <NUM> is biased by an internal spring into a natural state until being overcome by a force to urge the trigger arm <NUM> into a position away from the natural state position to an operational state. The sensor body <NUM> is mounted to the circuit board <NUM> and is operably coupled to the controller of electronics assembly, and is configured to transmit a sensor signal of an electronic characteristic (voltage, resistance, current signal) defined by the trigger arms movement to the controller. The trigger arm <NUM> may remain in the natural state until brought into engagement with the surface features <NUM>. After engagement between trigger arm <NUM> with the surface feature <NUM>, the trigger arm <NUM> may return to the natural state. According to <FIG>, the rotational sensor <NUM> is in the proximal position as the dose button <NUM> can be biased in its proximal position where the device <NUM> is in its first operating dose setting mode. The bias member (not shown) may be axially disposed between the dose button and the dose setting member, and the surface features <NUM> are disposed radially outside the bias member, such as shown in <FIG>. According <FIG>, the rotational sensor <NUM> is in the distal position as the dose button <NUM> is in its distal position where the device is in its second operating dose delivery mode.

<FIG> shows one example of a dose setting member having the surface features <NUM>. In one example, the axial surface <NUM> of the proximal end of the flange <NUM> may be integrally defined with the surface features, shown as projections <NUM> with intervening recesses <NUM>, such as a molded part or part made with additive manufacturing. In another example, a ring component with the surface features defined along one of its surfaces may be coupled to the axial surface of the flange. It will be appreciated that ring may be permanently or temporarily affixed to flange with an adhesives and/or fasteners. In another example, the surface features are formed or otherwise coupled to the dose dial member.

As shown in <FIG>, surface features <NUM> includes a series of projections <NUM> each having a ramp-like shape. Projections <NUM> may be formed with a surface which is ramped upward in the direction opposite to the direction of rotation, shown by arrow <NUM>, of the flange <NUM>. This further facilitates movement of the trigger arm <NUM> over the projections <NUM>. In another aspect, the opposite side of projections <NUM> may be ramped to allow for rotation of the dose setting member in the opposite direction. Further, the two sides of the projections <NUM> may be provided with different angles of inclination to allow the dose detection system to detect the direction of rotation. On the other hand, the opposite sides of the projections <NUM> may be angled more steeply to prevent rotation in the other direction.

The following embodiments illustrate different arrangements of the rotational sensor and surface features along a radial direction. <FIG> illustrates the proximal portion of the device, now referenced as <NUM>, depicting the rotational sensor of the dose detection system positioned radially outward relative to surface features that extend radially outward. The device <NUM> includes many of the same components operational for dose setting and dose dispensing as described with reference to the device <NUM>, <NUM>, or <NUM>, including at least a portion of the electronic components in the electronics assembly for the dose detection system, and such components will have the same corresponding descriptions. Although the device <NUM> is shown as a device within an integrated sensing system, such sensing system may be incorporated in a module for removable attachment to a dose button. Although the rotational sensor is shown as a microswitch that is similar to what is shown in <FIG>, the rotational sensor can be any of sensors described herein. The device <NUM> may have the same device components as device <NUM>, such as, for example, device housing <NUM>, dose dial member <NUM>, flange <NUM>, and electronics assembly <NUM>, except with respect to a different rotational sensor configuration and a different dose setting member with the surface features used for sensing, as will be described.

The rotational sensor <NUM> of the sensor system <NUM> is shown disposed along the annular wall portion <NUM> of the of the dose button <NUM>. The sensor body <NUM> of the rotational sensor <NUM> may be within an aperture <NUM> defined by the annular wall portion <NUM> or, in alternative embodiments, the sensor body <NUM> may be disposed along an interior surface of the wall portion <NUM>. The movable element comprises the trigger arm <NUM> that extends radially inward toward the longitudinal axis AA. Although not shown, the rotational sensor <NUM> is operably coupled to the controller of the electronics assembly, such as, via electrical conductors connected between the sensor <NUM> and the circuit board that extend along the interior surface of the dose button housing. The rotational sensor <NUM> is configured to transmit a sensor signal of an electronic characteristic (voltage, resistance, current signal) defined by movement of the trigger arm of the rotational sensor <NUM> to the controller.

<FIG> show the flange having the surface features. In one example, the outer radial surface <NUM> of a proximal annular end <NUM> of the flange <NUM> may be integrally defined with the surface features <NUM> that radially-spaced about the axis of rotation, shown as radial projections <NUM> with intervening recesses <NUM>, such as a molded part or part made with additive manufacturing. In another example, a ring component with the surface features <NUM> defined along the outer radial surfaces may be coupled to the axial surface of the flange. It will be appreciated that ring may be permanently or temporarily affixed to flange with an adhesives and/or fasteners. In another example, the surface features <NUM> are formed or otherwise coupled to the dose dial member. Surface features may include a series of ramp-like projections as described previously. The radial projections <NUM> may extend between a proximal end and a distal end to define axial ridges.

<FIG> illustrate the rotational sensor in the proximal position as the dose button <NUM> is in its proximal position where the device <NUM> is in its first operating dose setting mode. The dose button <NUM> is movable to its distal position (with reference to <FIG>) to place the rotational sensor in the distal position where the device is in its second operating dose delivery mode. In one example, the trigger arm <NUM> may enter through one of the recesses <NUM> from the proximal end when the dose button is being moved to its distal position so that the trigger arm is engageable with the surface features. Controller is capable of counting the number of times the trigger arm moves between a first trigger and last trigger and such data is used for determining a dose delivery.

<FIG> illustrates the proximal portion of the device, now referenced as <NUM>, depicting the rotational sensor positioned radially inward relative to surface features that extend radially inward. The device <NUM> includes many of the same components operational for dose setting and dose dispensing as described with reference to the device <NUM>, <NUM>, <NUM> or <NUM>, including at least a portion of the electronic components in the electronics assembly for the dose detection system <NUM>, and such components will have the same corresponding descriptions. Although the device <NUM> is shown as a device within an integrated sensing system, such sensing system may be incorporated in a module for removable attachment to a dose button. The device <NUM> may have the same device components as device <NUM>, such as, for example, device housing <NUM>, dose dial member <NUM>, flange <NUM>, dose button <NUM>, and electronics assembly <NUM>, except with respect to a different rotational sensor configuration and a different dose setting member with the surface features used for sensing, as will be described.

Like the arrangement of the rotational sensor <NUM>, the rotational sensor <NUM> is shown extending from the distal face of the circuit board through the axial aperture <NUM>. The sensor body of the rotational sensor <NUM> is mounted to the circuit board and is operably coupled to the controller of electronics assembly <NUM>, and is configured to transmit a sensor signal of an electronic characteristic (voltage, resistance, current signal) defined by movement of the movable element that is comprised of the trigger arm of the rotational sensor <NUM> to the controller. The mounting of the rotational sensor <NUM> is arranged to place its trigger arm within periphery of a proximal annular end <NUM> of the flange <NUM> and facing radially outward for engagement with the surface features <NUM>.

<FIG> show the flange <NUM> having the surface features. In one example, the inner radial surface <NUM> of the proximal annular end <NUM> of the flange <NUM> may be integrally defined with the surface features <NUM> that are radially-spaced about the axis of rotation, shown as projections <NUM> with intervening recesses <NUM>, such as a molded part or part made with additive manufacturing. In another example, a ring component with the surface features defined along the outer radial surfaces may be coupled to the axial surface of the flange. It will be appreciated that ring may be permanently or temporarily affixed to flange with an adhesives and/or fasteners. In another example, the surface features <NUM> are formed or otherwise coupled to the dose dial member. Surface features <NUM> may include a series of ramp-like projections. The surface features may extend between a proximal end and a distal end to define an axial ridge.

<FIG> illustrates a rotational sensor as a piezoelectric sensor <NUM>. The piezoelectric sensor <NUM> may be oriented similarly to the rotational sensors described above, such as axial, radially outward or radially inward. In one example, the trigger arm <NUM> of the piezoelectric sensor <NUM> is defined as a film of piezoelectric material that is bendable. The film extends from the sensor body <NUM>, and the sensor body <NUM> includes a first electrode <NUM> and a second electrode <NUM>. The sensor body may include a polymer cast housing, such as, for example, fluoropolymer (e.g., polyvinylidene fluoride) or polyurethane. Piezoelectric sensor <NUM> is a transducer that converts mechanical energy to electrical energy. More specifically, piezoelectric sensor <NUM> converts mechanical deformation of the trigger arm <NUM> to a proportional electrical signal (charge or voltage). Thus, when the trigger arm <NUM> of piezoelectric sensor is subjected to a mechanical force and undergoes deformation or strain, piezoelectric sensor <NUM> is configured to generate a proportional electrical signal between first electrode <NUM> and second electrode <NUM> for detection by an analog voltage detector of the electronics assembly. The mechanical deformation of trigger arm <NUM> of piezoelectric sensor <NUM> may be resilient, such that trigger arm <NUM> is able to return to its original, natural shape when the force is removed.

Controller of the electronics assembly may be configured to receive an analog piezoelectric signal from the voltage detector of each piezoelectric sensor <NUM>, which may be a substantially ring-shaped signal. Controller of the electronics assembly may be programmed to convert the analog piezoelectric signal to a digital signal, such as, for example, an intermediate digital signal, which may be a high-frequency signal that represents the time of the "click" or deformation event. Controller of the electronics assembly may be further programmed to convert the intermediate digital signal to a conditioned digital signal, which may be a single step/square wave with a predetermined width W representing a predetermined time, as described further below.

A signal processing logic for use by control system. Logic subject the analog piezoelectric signal to a direct current (DC) voltage offset step using resistors, followed by an amplification step using amplifier, and followed by an analog-to-digital conversion step using comparator to generate the intermediate digital signal. The signal may be generated when the incoming voltage is at or above a predetermined voltage (e.g., <NUM> V). Alternatively, the signal may be ignored when the incoming voltage is less than the predetermined voltage. The intermediate digital signal may be converted to the conditioned digital signal by turning the signal "on" when initiating a timer at a timer initiation step and turning the signal "off" when the timer expires after a predetermined time at a timer expiration step. The timing steps may be performed using a resistance-capacitance (RC) timing loop. The predetermined time associated with the timing steps may control the width W of the conditioned digital signal and may be adjusted to match the time of each rotation and deformation event to minimize errors. Logic may output a number corresponding to the number of digital signals counted over a period of time.

The devices described herein, such as, for example, devices <NUM>, <NUM>, <NUM> or <NUM>, may include the dose detection system involving detecting relative rotational movement between two members. With the extent of rotation having a known relationship to the amount of a delivered dose, the sensor system in any of the embodiments described herein operates to detect the amount of angular movement from the start of a dose injection to the end of the dose injection. The angular displacement is determined by counting increments of dose amounts as the injection proceeds. For example, a sensing system may use a repeating pattern of a sensed element, such that each repetition is an indication of a predetermined degree of angular rotation. Conveniently, the pattern may be established such that each repetition corresponds to the minimum increment of dose that can be set with the medication delivery device. Controller is configured to count the number of generated signals. The count may be transmitted electronically to an external device. External device described herein may refer to a server, mobile phone, or other known computer systems. The count may be correlated to an absolute rotational angle, which is then used by a processor of the external device to determine the amount of dose delivered. The signal generated by the initial contact of the contacts may be operable to wake-up or activate the controller, as previously described.

In the manner previously described, any of the rotational sensors described herein, such as rotational sensors <NUM>, <NUM>, <NUM>, <NUM>, detects angular movement of the dose setting member by counting the number of surface features that trigger activation of trigger arm during dose delivery. Each of rotational sensors generates signals indicating this angular movement and those generated signals are used by the controller of electronics assembly to determine the total number of counts or units. Such total number of counts have a corresponding total rotation of the dose setting member during dose delivery, and thereby the amount of the dose delivery. In one example, each of the rotational sensors generates signals indicative of a count number and the controller receives the generated signal. Controller may store the number of counts on-board in internal memory and/or transmit the number of counts to an external device. Controller may compare the number of counts to an on-board database that correlates number of counts to a total angular movement. The determined angular movement may be displayed on a local display and/or transmitted to an external device.

The devices described herein, such as, for example, devices <NUM>, <NUM>, <NUM> or <NUM>, may include the wake-up feature described herein, where the depression of the dose button to its distal position during initial dose delivery can activate the controller. For example, upon the sensing of the initial one of surface features, the controller of electronics assembly is configured to allow wake-up or activate the electronics assembly to a full power state. Triggering of wake-up feature is configured to allow power transmission from the power source (shown as battery) for powering up the electronic components for dose sensing in order to minimize inadvertent power loss or usage when a dose dispensing event is not occurring. In other embodiments, a separate wake-up switch may be provided and arranged within the dose button housing of any one of the devices described herein and triggered when the dose button is in its distal position. In this instance, the wake-up switch may be located, for example, along the upper end of the flange.

In some embodiments, a single sensing system may be employed for both dose detection sensing and wake-up activation. For example, the devices described herein, such as, for example, devices <NUM>, <NUM>, <NUM> or <NUM>, may have a controller configured to, upon the sensing of the initial first surface feature, allow wake-up or activation of the electronics assembly to a full power state. Subsequently, the controller is configured to, upon the sensing of the first surface feature (or second in order) after the initial first surface feature, count the total number of surface features until rotation of the dose setting member is stopped upon completion of the dose dispensing phase. One of the advantages of a single system with this abundant functionality is that may reduce the number of electronic components in the device as well as the manufacturing complexity with additional sensors.

The shown device is a reusable pen-shaped medication injection device, generally designated, which is manually handled by a user to selectively set a dose and then to inject that set dose. Injection devices of this type are well known, and the description of device is merely illustrative as the sensing system can be adapted for use in variously configured medication delivery devices, including differently constructed pen-shaped medication injection devices, differently shaped injection devices, and infusion pump devices. The medication may be any of a type that may be delivered by such a medication delivery device. Device is intended to be illustrative and not limiting as the sensing system described further below may be used in other differently configured devices.

To clarify the use of and to hereby provide notice to the public, the phrases "at least one of <A>, <B>,. and <N>" or "at least one of <A>, <B>,. <N>, or combinations thereof" or "<A>, <B>,. and/or <N>" are defined by the Applicant in the broadest sense, superseding any other implied definitions hereinbefore or hereinafter unless expressly asserted by the Applicant to the contrary, to mean one or more elements selected from the group comprising A, B,. In other words, the phrases mean any combination of one or more of the elements A, B,. or N including any one element alone or the one element in combination with one or more of the other elements which may also include, in combination, additional elements not listed.

Claim 1:
A medication delivery device (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) comprising:
a device body (<NUM>);
a dose setting member (<NUM>, <NUM>) attached to said device body and rotatable relative to said device body about an axis of rotation (AA) during dose delivery; and
an actuator (<NUM>, <NUM>) attached to said device body;
characterized in that the medication delivery device further comprises:
a sensed element (<NUM>) attached to and rotationally fixed with said dose setting member, said sensed element including axially extending surface features (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) radially-spaced from one another about the axis of rotation of said dose setting member, wherein said sensed element is rotatable relative to said actuator during dose delivery in relation to the amount of dose delivered;
a rotational sensor (<NUM>, <NUM>, <NUM>, <NUM>, <NUM>) attached to said actuator, wherein said rotational sensor comprises a switch, said rotational sensor including a movable element (<NUM>, <NUM>. <NUM>, <NUM>) positionable to slidably contact the axially extending surface features during rotation of said sensed element relative to said actuator during dose delivery, said rotational sensor configured to generate a signal in response to a triggering of the movable element over the axially extending surface features during the rotation of said dose setting member, wherein the movable element alternately engaging or disengaging the axially extending surface features is operable to trigger the switch and generate said signal; and
a controller (<NUM>) operatively coupled to the rotational sensor, wherein, in response to receiving the generated signal from said rotational sensor, the controller is configured to determine a number of the axially extending surface features passing the movable element of the rotational sensor during dose delivery.