Absolute Position Determination of Movably Mounted Member in Medication Delivery Device

• US 20110181301A1
• Filed: 04/12/2007
• Published: 07/28/2011
• Est. Priority Date: 04/12/2006
• Status: Active Grant

• Current Assignee: Novo Nordisk A/S
• Original Assignee: Novo Nordisk A/S
• Inventors: Nielsen, Preben, von Münchow, Bodo, Sørensen, Peter Grønning
• Granted Patent: US 8,994,382 B2
• Time in Patent Office: Days
• US Class Current: 324/649
• CPC Class Codes: A61M 2205/3317 Electromagnetic, inductive or dielectric measuring means
• CPC Class Codes: A61M 5/31525 Dosing burettes, pipettes B01L3/02
• CPC Class Codes: A61M 5/31533 Dosing mechanisms, i.e. setting a dose administrating mechanisms A61M5/31565
• CPC Class Codes: A61M 5/3155 by rotational movement of dose setting member, e.g. during setting or filling of a syringe
• CPC Class Codes: A61M 5/31556 Accuracy improving means
• CPC Class Codes: G01D 5/1655 more than one point of contact or actuation on one or more tracks

Abstract

The present invention relates to a medication delivery device for expelling set doses of medicament, the medication delivery device comprising a position determining arrangement for detecting absolute positions of a movably mounted member, such as a dose indicator barrel, relative to a housing of the medication delivery device. The position determining arrangement comprises a plurality of electrically conducting electrodes arranged on an outer surface of the movably mounted member, and a plurality of contacts members fixedly arranged relative to the housing of the medication delivery device. A first and a second contact member are arranged to follow a first path across the electrically conducting electrodes upon movement of the movably mounted member relative to the housing, whereas a third and a fourth contact member are arranged to follow a second path across the electrically conducting electrodes upon movement of the movably mounted member relative to the housing.

Claims

1. A medication delivery device comprising a position determining assembly for determining absolute positions of a first member relative to a second member of the medication delivery device, the position determining assembly comprising:

first and second electrically conducting electrodes arranged on the first member, wherein the first and second electrically conducting electrodes are electrically connected through an electronic device having a measurable electronic value, and wherein the first and second electrically conducting electrodes form part of a first group of electrodes,

first and second contact members being adapted to establish galvanic electrical connections to the first and second electrically conducting electrodes, said first and second contact members further being adapted to be slid across the first and second electrically conducting electrodes when the first member is moved relative the second member, and

an electronic control circuit electrically coupled to the first and second contact members, the electronic control circuit being adapted to determine the measurable electronic value of the electronic device, the electronic control circuit further being adapted to compare a determined measurable electronic value with a set of predetermined values.

2. A medication delivery device according to claim 1, wherein the first and second electrically conducting electrodes are arranged on an outer surface part of the first member.

3. A medication delivery device according to claim 1, wherein the first member forms part of a movably mounted member arranged within a housing of a medication delivery device.

4. A medication delivery device according claim 1, wherein the second member forms part of a housing of a medication delivery device.

5. A medication delivery device according to claim 1, wherein the first group of electrodes comprises additional electrically conducting electrodes being connected through respective electronic devices each having a measurable electronic value.

6. A medication delivery device according to claim 1, further comprising a second group of electrically conducting electrodes being connected through respective electronic devices each having a measurable electronic value.

7. A medication delivery device according to claim 6, further comprising third and fourth contact members being adapted to establish galvanic electrical connections to electrically conducting electrodes of the second group, said third and fourth contact members further being adapted to be slid across electrically conducting electrodes of the second group when the first member is moved relative to the second member.

8. A medication delivery device according to claim 7, wherein the electrically conducting electrodes of each of the first and second groups of electrodes are arranged in a periodic structure along a predetermined direction.

9. A medication delivery device according to claim 1, wherein the first member is adapted to perform a translational movement relative to the second member.

10. A medication delivery device according to claim 1, wherein the first member is adapted to perform a rotational movement relative to the second member.

11. A medication delivery device according to claim 1, wherein the first member is adapted to perform a combined rotational and translational movement relative to the second member.

12. A medication delivery device according to claim 1, wherein the electronic devices connecting the electrically conducting electrodes comprise a number of resistors.

13. A medication delivery device according to claim 1, wherein the electronic devices connecting the electrically conducting electrodes comprise a number of capacitors.

14. A medication delivery device according to claim 1, wherein the electronic devices connecting the electrically conducting electrodes comprise a number of inductors.

15. A medication delivery device according to claim 1, wherein the contact members are mechanically biased towards the first member.

16. A medication delivery device according to claim 1, wherein the contact members are arranged in a fixed relationship with a housing of the medication delivery device.

17. A medication delivery device according to claim 1, wherein the first member forms part of a rotatably mounted dose indicator barrel.

18. A method for determining absolute positions of a first member relative to a second member of a medication delivery device, the method comprising:

providing first and second electrically conducting electrodes arranged on the first member, wherein the first and second electrically conducting electrodes are electrically connected through an electronic device having a measurable electronic value, and wherein the first and second electrically conducting electrodes form part of a first group of electrodes,

providing first and second contact members being adapted to establish galvanic electrical connections to the first and second electrically conducting electrodes, said first and second contact members further being adapted to be slided across the first and second electrically conducting electrodes when the first member is moved relative to the second member, and

determining the measurable electronic value of the electronic device, and comparing the determined measurable electronic value with a set of predetermined values.

19. A method according to claim 18, wherein the determining of the measurable electronic value, and the comparison of the determined measurable electronic value with a set of predetermined values is performed by an electronic control circuit integrated in the medication delivery device,

20. A method according to claim 18, wherein the first and second electrically conducting electrodes are arranged on an outer surface part of the first member.

21. A method according to claim 18, further comprising of determining additional measurable electronic values of respective ones of additional electronic devices connecting additional electrically conducing electrodes of the first group, and comparing the determined additional measurable electronic values with the set of predetermined values.

22. A method according to claim 21, further comprising providing third and fourth contact members being adapted to establish galvanic electrical connections to electrically conducting electrodes of a second group, said third and fourth contact members further being adapted to be slid across electrically conducting electrodes of the second group when the first member is moved relative to the second member.

23. A method according to claim 22, further comprising:

determining measurable electronic values of respective ones of electronic devices connecting electrically conducing electrodes of the second group of electrodes, and comparing the determined measurable electronic values with a set of predetermined values.

24. A method according to claim 18 any of claims 18-23, wherein the predetermined values are arranged in a look-up table.

25. A method according to claim 18, wherein the determined measurable electronic values comprise a resistance.

26. A method according to claim 18, wherein the determined measurable electronic values comprise a capacitance.

27. A method according to claim 18, wherein the determined measurable electronic values comprise an inductance.

28. A method according to claim 18, wherein the first member is adapted to perform a translational movement relative to the second member.

29. A method according to claim 18, wherein the first member is adapted to perform a rotational movement relative to the second member.

30. A method according to claim 18, wherein the first member is adapted to perform a combined rotational and translational movement relative to the second member.

31. A method according to claim 18, wherein the contact members are mechanically biased towards the first member.

32. A method according to claim 18, wherein the contact members are arranged in a fixed relationship with the second member.

33. A method according to claim 18, wherein the first member forms part of a rotatably mounted dose indicator barrel.

34. A method according to claim 18, wherein the second member forms part of a housing of the medication delivery device.