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EP-4431135-B1 - DETERMINING A STATUS OF AN INJECTION

EP4431135B1EP 4431135 B1EP4431135 B1EP 4431135B1EP-4431135-B1

Inventors

  • HELMER, MICHAEL

Dates

Publication Date
20260513
Application Date
20181218

Claims (15)

  1. A drug delivery device (102) comprising: a housing (203); a first magnet (402a) and a second magnet (404a), wherein the first and second magnets are of opposite polarity and wherein the first and second magnets are incorporated into the housing of the drug delivery device; and a first Wiegand wire (224) comprising an inner core and an outer shell, the first Wiegand wire having a starting position proximate to the first magnet (402a) and a target position proximate to the second magnet (404a), wherein a magnetization polarity of the inner core of the first Wiegand wire (224) is configured to switch as the first Wiegand wire (224) moves to the target position proximate to the second magnet (404a) and this switch is configured to induce a first voltage pulse in a first coil (406a) of a first sensor assembly (304).
  2. The drug delivery device (102) of claim 1, wherein the drug delivery device comprises a pump.
  3. The drug delivery device (102) of claim 1 or claim 2, wherein the target position of the first Wiegand wire (224) corresponds to a holding position of the drug delivery device at an injection site.
  4. The drug delivery device (102) of any preceding claim, further comprising a needle shield (220) having an extended position, a retracted position and a further retracted position, and wherein the first Wiegand wire is provided on the needle shield (220).
  5. The drug delivery device (102) of claim 4, wherein when the needle shield (220) is in the extended position, the first Wiegand wire (224) is in the starting position proximate to the first magnet (402a) and when the needle shield is in the further retracted position, the first Wiegand wire (224) is in the target position proximate to the second magnet (404a).
  6. The drug delivery device (102) of claim 5, wherein a time at which the first voltage pulse is induced in the first coil (406A) is indicative of a start of a holding time of the injection.
  7. The drug delivery device (102) of any of claims 4 to 6, wherein a magnetization polarity of the outer shell of the first Wiegand wire (224) is configured to switch during movement of the needle shield (220) from the extended position to the retracted position, and this switch is configured to induce a further voltage pulse in the first coil (406a).
  8. The drug delivery device (102) of claim 7, wherein a time at which the further voltage pulse is induced in the first coil (406A) is indicative of the start time of the injection.
  9. The drug delivery device (102) of any preceding claim, wherein the first sensor assembly (304) is provided in an electronic device (104) comprising a processor (308) and a housing (302) for attachment to the drug delivery device (102) and wherein the first coil (406a) is configured to provide a signal to the processor in response to the induced first voltage pulse.
  10. The drug delivery device (102) of any of claims 1 to 9, comprising: a second Wiegand wire (226) comprising an inner core and an outer shell; and two magnets (402b, 404b) of opposite polarity, wherein the two magnets (402b, 404b) are incorporated into the housing (203) of the drug delivery device, wherein the magnetization polarity of the inner core of the second Wiegand wire (226) is configured to switch as the second Wiegand wire (226) moves from a first position proximate to one of the magnets (404b) to a second position toward the other magnet (402b) and this switch is configured to induce a second voltage pulse in a second coil (406b) of a second sensor assembly (306).
  11. The drug delivery device (102) of claim 10, wherein the second Wiegand wire is positioned on a piston (208) and wherein the piston is part of a drive mechanism (206) configured to cause medicament to be ejected from a cartridge, the drive mechanism having a retracted position and a substantially extended position.
  12. The drug delivery device (102) of claim 11, wherein when the drive mechanism (206) is in the retracted position, the second Wiegand wire (226) is in the first position proximate to one of the magnets (402a) and when the drive mechanism (206) is in the substantially extended position, the second Wiegand wire (226) is in the second position proximate to the other magnet (402b).
  13. The drug delivery device (102) of claim 12, wherein the second position of the second Wiegand wire (226) corresponds to an end time of an injection.
  14. The drug delivery device (102) of any of claims 10 to 13, wherein the second sensor assembly (306) is provided in an electronic device (104) comprising a processor (308) and a housing (302) for attachment to the drug delivery device (102) and wherein the second coil (406b) is configured to provide a signal to the processor in response to the induced second voltage pulse.
  15. The drug delivery device (102) of claim 14, wherein the processor (308) is configured to enter an enabled state from a sleep state after receiving the first voltage pulse from the first coil (406a).

Description

TECHNICAL FIELD This disclosure relates to determining a status of an injection, and more particularly, to determining a status of an injection of medicament administered by an injection device. BACKGROUND A variety of diseases can be treated by injection of a medicament. Such injection can be performed using injection devices, which are applied either by medical personnel or by patients themselves. As an example, type-1 and type-2 diabetes can be treated by patients themselves by injection of insulin doses, for example once or several times per day. For instance, a pre-filled disposable insulin pen or autoinjector can be used as an injection device. Alternatively, a re-usable pen or autoinjector may be used. A disposable or re-usable pen or autoinjector allows replacement of an empty medicament cartridge by a new one. Either type of pen or autoinjector may come with a set of one-way needles that are replaced before each use. DE 10 2008 031795 A1 discloses a device for administering or dispensing a substance, in particular an injection device or a pen or an infusion device, which has a metering element for the dosed administration of an injectable product which can interact with an electronic control. A pulse wire sensor and, in particular, a Wiegand sensor, with which magnetic fields can be detected, can be used as a generator sensor. For example, one or more permanent magnets can be connected to at least one of the movable parts of the administering device. SUMMARY A first aspect provides a drug delivery device (102) comprising: a housing (203); a first magnet (402a) and a second magnet (404a), wherein the first and second magnets are of opposite polarity and wherein the first and second magnets are incorporated into the housing of the drug delivery device; and a first Wiegand wire (224) comprising an inner core and an outer shell, the first Wiegand wire having a starting position proximate to the first magnet (402a) and a target position proximate to the second magnet (404a), wherein a magnetization polarity of the inner core of the first Wiegand wire (224) is configured to switch as the first Wiegand wire (224) moves to the target position proximate to the second magnet (404a) and this switch is configured to induce a first voltage pulse in a first coil (406a) of a first sensor assembly (304). The drug delivery device may comprises a pump. The target position of the first Wiegand wire (224) may correspond to a holding position of the drug delivery device at an injection site. The drug delivery device may further comprise a needle shield (220) having an extended position, a retracted position and a further retracted position, and wherein the first Wiegand wire may be provided on the needle shield (220). When the needle shield (220) is in the extended position, the first Wiegand wire (224) may be in the starting position proximate to the first magnet (402a) and when the needle shield is in the further retracted position, the first Wiegand wire (224) may be in the target position proximate to the second magnet (404a). A time at which the first voltage pulse is induced in the first coil (406A) may be indicative of a start of a holding time of the injection. A magnetization polarity of the outer shell of the first Wiegand wire (224) may be configured to switch during movement of the needle shield (220) from the extended position to the retracted position, and this switch may be configured to induce a further voltage pulse in the first coil (406a). A time at which the further voltage pulse is induced in the first coil (406A) may be indicative of the start time of the injection. The first sensor assembly (304) may be provided in an electronic device (104) comprising a processor (308) and a housing (302) for attachment to the drug delivery device (102) and wherein the first coil (406a) may be configured to provide a signal to the processor in response to the induced first voltage pulse. The drug delivery device (102) may further comprise: a second Wiegand wire (226) comprising an inner core and an outer shell; and two magnets (402b, 404b) of opposite polarity, wherein the two magnets (402b, 404b) are incorporated into the housing (203) of the drug delivery device, wherein the magnetization polarity of the inner core of the second Wiegand wire (226) is configured to switch as the second Wiegand wire (226) moves from a first position proximate to one of the magnets (404b) to a second position toward the other magnet (402b) and this switch is configured to induce a second voltage pulse in a second coil (406b) of a second sensor assembly (306). The second Wiegand wire may be positioned on a piston (208) and wherein the piston is part of a drive mechanism (206) configured to cause medicament to be ejected from a cartridge, the drive mechanism having a retracted position and a substantially extended position. When the drive mechanism (206) is in the retracted position, the second Wiegand wire (226) may be in the firs