Injection Device Comprising An Optical Sensor

• US 20120215162A1
• Filed: 05/01/2012
• Published: 08/23/2012
• Est. Priority Date: 05/10/2005
• Status: Active Grant

• Current Assignee: Novo Nordisk A/S
• Original Assignee: Novo Nordisk A/S
• Inventors: NIELSEN, Preben Mikael, VON MUNCHOW, Bodo, PEDERSEN, Carsten Bitsch, PEDERSEN, Per Molgaard
• Granted Patent: US 8,771,238 B2
• Time in Patent Office: Days
• US Class Current: 604/65
• CPC Class Codes: A61M 2205/3306 Optical measuring means
• CPC Class Codes: A61M 2205/6063 Optical identification systems
• CPC Class Codes: A61M 5/31525 Dosing burettes, pipettes B01L3/02
• 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: A61M 5/31568 Means keeping track of the total dose administered, e.g. since the cartridge was inserted
• CPC Class Codes: G01D 5/3473 Circular or rotary encoders
• CPC Class Codes: G01D 5/34792 with only digital scales or both digital and incremental scales

Abstract

The present invention relates to an injection device comprising an optically-based sensor for determining the position or setting of a dose setting member arranged to set a dose to be injected from the injection device. In particular, the present invention relates to an injection device comprising a rotatably mounted member having a plurality of optically coded paths arranged on an outer surface thereof. The rotatably mounted member is operatively connected to the dose setting member and is adapted to rotate with the dose setting member.

Claims

1. A method for determining the position or setting of a dose setting member adapted to set a dose of a medicament to be injected from an injection device comprising a dose setting member, the dose setting member being operatively connected to a rotatably mounted member (1), the method comprising:

projecting a plurality of light beams onto a plurality of optically coded tracks provided on an outer surface of a rotatably mounted member, the optically coded tracks being arranged as parallel helically extending tracks on the rotatably mounted member, and

detecting light intensities of a plurality of light beams reflected from the optically coded tracks, and

determining the position or setting of the dose setting member from the detected intensities.

2. The method according to claim 1, wherein the number of light beams equals the number of optically coded tracks provided on the rotatably mounted member.

3. The method according to claim 1, wherein the intensity of the plurality of optical light beams varies in accordance with the position of the dose setting member in that the reflectivity or transparency of the outer surface of the rotatably mounted member varies along the optically coded tracks.

4. The method according to claim 1, wherein the number of light beams projected onto the outer surface of the rotatably mounted member and the number of light beams reflected thereof is equal to six.

5. The method according to claim 1, further comprising providing information concerning the detected light intensities to a control circuit, said control circuit being adapted to calculate the position or setting of the dose setting member.

6. An arrangement for determining the position of a dose setting member adapted to set a dose of a medicament to be injected from an injection device, the arrangement comprising:

a rotatably mounted member having a plurality of optically coded tracks arranged on an outer surface thereof,

a light generator for generating and guiding a plurality of light beams towards the rotatably mounted member, and

structure for guiding a plurality of light beams from the rotatably mounted member to a plurality of light sensitive elements or areas.

8. The arrangement according to claim 6, wherein the optically coded tracks are provided by varying the optical properties along said tracks.

9. The arrangement according to claim 8, wherein the optical properties along the tracks paths are varied by varying an optical reflectivity or transparency of the outer surface of the rotatably mounted member.

10. The arrangement according to any of claim 6, wherein six optically coded tracks paths are arranged on the outer surface of the rotatably mounted member.

11. The arrangement according to claim 6, further comprising structure for guiding a plurality of guided light beams, each light beam being guided so as to be incident on one optically coded track path.

12. The arrangement according to claim 11, wherein the number of guided light beams equals the number of optically coded tracks paths.

13. The arrangement according to claim 11, further comprising a light detector, the light detector comprising a plurality of light sensitive elements.

14. The arrangement according to claim 13, wherein the number of light sensitive elements equals the number of optically coded tracks.

15. The arrangement according to claim 13, further comprising structure for guiding a plurality of light beams reflected from the optically coded tracks-to the light sensitive elements.

16. The arrangement according to claim 11, wherein the light guiding structure arranged to provide light beams to and from the optically coded tracks-are arranged as through-going openings in a housing.

17. The arrangement according to claim 16, wherein the light guiding structure for guiding light to the optically coded tracks are arranged so that the light beams are incident onto the optically coded tracks-under an angle of 40-50 degrees.

18. The arrangement according to claim 16, wherein the light guiding structure for guiding light from the optically coded tracks-to the light sensitive elements are arranged so that the light beams leave the optically coded tracks-under an angle of 40-50 degrees.

19. The arrangement according to claim 6, wherein the rotatably mounted member is at least partly transparent.

20. The arrangement according to claim 19, further comprising a light emitter adapted to couple a beam of light into the rotatably mounted member.

21. The arrangement according to claim 20, further comprising light detecting structure having a plurality of light sensitive areas, the light detecting structure being arranged to detect light escaping the outer surface of the rotatably mounted member.

22. The arrangement according to claim 21, wherein the number of light sensitive areas equals the number of optically coded tracks.

7. An arrangement for determining an amount of a medicament injected from an injection device, the arrangement comprising:

a rotatably mounted member having a plurality of optically coded tracks arranged on an outer surface thereof,

a light generator for generating and guiding a plurality of light beams towards the rotatably mounted member, and

structure for guiding a plurality of light beams from the rotatably mounted member to a plurality of light sensitive elements or areas.

23. The arrangement according to claim 7, wherein the optically coded tracks paths are provided by varying the optical properties along said tracks.

24. The arrangement according to claim 23, wherein the optical properties along the tracks-are varied by varying an optical reflectivity or transparency of the outer surface of the rotatably mounted member.

25. The arrangement according to any of claim 7, wherein six optically coded tracks-are arranged on the outer surface of the rotatably mounted member.

26. The arrangement according to claim 7, further comprising structure for guiding a plurality of guided light beams, each light beam being guided so as to be incident on one optically coded path.

27. The arrangement according to claim 26, wherein the number of guided light beams equals the number of optically coded tracks.

28. The arrangement according to claim 26, further comprising a light detector, the light detector comprising a plurality of light sensitive elements.

29. The arrangement according to claim 28, wherein the number of light sensitive elements equals the number of optically coded tracks.

30. The arrangement according to claim 28, further comprising structure for guiding a plurality of light beams reflected from the optically coded tracks-to the light sensitive elements.

31. The arrangement according to claim 26, wherein the light guiding structure arranged to provide light beams to and from the optically coded tracks-are arranged as through-going openings in a housing.

32. The arrangement according to claim 31, wherein the light guiding structure for guiding light to the optically coded tracks-are arranged so that the light beams are incident onto the optically coded tracks-under an angle of 40-50 degrees.

33. The arrangement according to claim 31, wherein the light guiding structure for guiding light from the optically coded tracks-to the light sensitive elements are arranged so that the light beams leave the optically coded tracks-under an angle of 40-50 degrees.

34. The arrangement according to claim 7, wherein the rotatably mounted member is at least partly transparent.

35. The arrangement according to claim 34, further comprising a light emitter adapted to couple a beam of light into the rotatably mounted member.

36. The arrangement according to claim 35, further comprising light detecting structure having a plurality of light sensitive areas, the light detecting structure being arranged to detect light escaping the outer surface of the rotatably mounted member.

37. The arrangement according to claim 36, wherein the number of light sensitive areas equals the number of optically coded tracks.

38. An injection device comprising:

a dose setting member adapted to set a dose of a medicament to be injected from the injection device,

a position determining arrangement for determining the amount of a set dose or the amount of an injected dose, the position determining arrangement comprising a rotatably mounted member having a plurality of parallel optically coded tracks arranged on an outer surface thereof,

an optic sensor arrangement adapted to sense the optically coded tracks, and

a control circuit coupled to the optic sensor arrangement to determine the position of the rotatably mounted member relative to the optic sensor arrangement,

wherein the optically coded tracks are arranged as helically extending tracks on the rotatably mounted member.

39. An injection device according to claim 38, wherein the optically coded tracks are provided by varying the optical properties along said tracks.

40. An injection device according to claim 39, wherein the optical properties along the tracks are varied by varying the optical reflectivity or transparency of the outer surface of the rotatably mounted member.

41. An injection device according to claim 38, wherein six optically coded tracks are arranged on the outer surface of the rotatably mounted member.

42. An injection device according to claim 38, further comprising means for guiding a plurality of guided light beams, each light beam being guided so as to be incident on one optically coded track.

43. An injection device according to claim 42, wherein the number of guided light beams equals the number of optically coded tracks.

44. An injection device according to claim 42, wherein the optic sensor arrangement comprise a plurality of light sensitive elements.

45. An injection device according to claim 44, wherein the number of light sensitive elements equals the number of optically coded tracks.

46. An injection device according to claim 44, further comprising means for guiding a plurality of light beams reflected from the optically coded tracks to the light sensitive elements.

47. An injection device according to any of claims 42, wherein the light guiding means arranged to provide light beams to and from the optically coded tracks are arranged as through-going openings in a housing.

48. An injection device according to claim 47, wherein the light guiding means for guiding light to the optically coded tracks are arranged so that the light beams are incident onto the optically coded tracks under an angle of 40-50 degrees.

49. An injection device according to claim 47, wherein the light guiding means for guiding light from the optically coded tracks to the light sensitive elements are arranged so that the light beams leave the optically coded tracks under an angle of 40-50 degrees.

50. An injection device according to any of claims 38, wherein the rotatably mounted member is at least partly transparent.

51. An injection device according to claim 50, further comprising light emitting means adapted to emit a beam of light into the rotatably mounted member.

52. An injection device according to claim 51, further comprising light detecting means having a plurality of light sensitive areas, the light detecting means being arranged to detect light escaping the outer surface of the rotatably mounted member.

53. An injection device according to claim 52, wherein the number of light sensitive areas equals the number of optically coded tracks.