DRIVE UNIT FOR MEDICAL DEVICES

• US 20080007141A1
• Filed: 08/01/2007
• Published: 01/10/2008
• Est. Priority Date: 02/01/2005
• Status: Active Grant

• Current Assignee: Roche Diabetes Care Inc. (Roche Holding AG)
• Original Assignee: Roche Diagnostics Operations Incorporated (Roche Holding AG)
• Inventors: Deck, Frank
• Granted Patent: US 7,456,550 B2
• Time in Patent Office: Days
• US Class Current: 310/328
• CPC Class Codes: A61B 5/150022 for capillary blood or interstitial fluid
• CPC Class Codes: A61B 5/150358 Strips for collecting blood, e.g. absorbent optical reagent test strips G01N21/8483; chemical reagent test strips G01N33/4875, G01N33/52
• CPC Class Codes: A61B 5/15107 Piercing being assisted by a triggering mechanism
• CPC Class Codes: A61B 5/15117 comprising biased elements, resilient elements or a spring, e.g. a helical spring, leaf spring, or elastic strap
• CPC Class Codes: A61B 5/15146 Devices loaded with multiple lancets simultaneously, e.g. for serial firing without reloading, for example by use of stocking means. multiple simultaneous cutting or piercing A61B5/150977
• CPC Class Codes: H02N 2/043 Mechanical transmission means, e.g. for stroke amplification
• CPC Class Codes: H02N 2/10 producing rotary motion, e.g. rotary motors

Abstract

The invention relates to a drive unit for a medical device such as an insulin pump, lancing device, or test strip magazine. The drive unit comprises an actuator for charging a mechanical energy storage element. The actuator oscillates and executes travel strokes which are transmitted by means of a step-up element to a nonreturn rotor or traveler for prestressing the mechanical energy storage element and driving a movement element.

Claims

1. A drive unit for a medical device, comprising:

a mechanical energy store;

an actuator which oscillates;

a nonreturn rotor or traveler for prestressing the mechanical energy store; and

a step-up element configured to transmit travel strokes of the actuator to the nonreturn rotor or traveler.

2. The drive unit of claim 1 further comprising an output shaft operably connected to the mechanical energy store.

3. The drive unit of claim 1 further comprising a plunger configured for pushing a medical commodity from a magazine, the plunger being operably connected to the mechanical energy store.

4. The drive unit of claim 1 further comprising a pump which administers a medically active substance, the pump being operably connected to the mechanical energy store.

5. The drive unit of claim 1, wherein the step-up element amplifies the stroke of the actuator in a ratio of at least 1:

25 and transmits the amplified stroke to the nonreturn rotor or traveler.

6. The drive unit of claim 5, wherein the step-up element further comprises a restoring spring.

7. The drive unit of claim 6, wherein the nonreturn rotor comprises a ratchet wheel having teeth on its outer circumference.

8. The drive unit of claim 1, wherein the mechanical energy storage element comprises a spring element.

9. The drive unit of claim 1, wherein the step-up element comprises a first and a second lever arm having different lengths.

10. The drive unit of claim 9, wherein the actuator actuates one of the lever arms and the other of the lever arms actuates the nonreturn rotor or traveler.

11. The drive unit of claim 1, wherein the step-up element comprises a rocker in a device housing having a first and a second lever arm, the second lever arm configured to actuate a pivoting cam which rotates an output shaft.

12. The drive unit of claim 11, wherein the output shaft comprises a first clamping roller freewheel coupled to the pivoting cam and a second clamping roller freewheel coupled to the device housing.

13. The drive unit of claim 11, wherein the step-up element further comprises a spring-loaded pressure piece having a spherical head.

14. The drive unit of claim 1, further comprising a nonreturn element which counteracts a backward movement of the nonreturn rotor when the stroke movement of the actuator is reversed.

15. The drive unit of claim 14, wherein the nonreturn rotor comprises a ratchet wheel or a linear traveler having teeth.

16. The drive unit of claim 15, wherein the nonreturn element comprises a pawl configured to engage teeth of the ratchet wheel or the linear traveler.

17. The drive unit of claim 14, wherein the nonreturn element comprises a clamping body freewheel.

18. The drive unit of claim 1, wherein the nonreturn rotor or traveler comprises a nonreturn traveler having a first traveler side, a second traveler side, and a linear guide, the linear guide configured to receive the nonreturn traveler.

19. The drive unit of claim 18, wherein one of the two traveler sides comprises a comb-shaped rib structure that prevents a return movement of the nonreturn traveler.

20. The drive unit of claim 1, further comprising a lever pincer which is actuated by the actuator, the lever pincer having first and second pincer legs articulated by a joint.

21. The drive unit of claim 20, wherein the pincer legs comprise extension surfaces having drive cams that actuate a drive bell.

22. The drive unit of claim 21, wherein the drive bell surrounds a freewheel.

23. The drive unit of claim 22, wherein the freewheel is rotationally fixed on an output shaft.

24. The drive unit of claim 1, wherein the actuator comprises a piezoactuator, the stroke travel of the actuator being transmitted to the step-up element when a voltage is applied to the piezoactuator.

25. The drive unit of claim 1, wherein the actuator comprises a diaphragm configured to deflect when a cavity thereof is acted upon by pressure, thereby generating the travel strokes.

26. The drive unit of claim 1, wherein the actuator comprises a micromotor having an output shaft coupled to a cam that deflects the step-up element.

27. The drive unit of claim 26, wherein the cam is configured to deflect the step-up element at least once during a full rotation of the output shaft.

28. A drive unit for a medical device, comprising:

a mechanical energy storage element;

an actuator; and

a transmission element;

wherein the actuator produces oscillating travel strokes which oscillate the transmission element, the oscillations of the transmission element being at least partially transferred to the mechanical energy storage element as stored mechanical energy.

29. The drive unit of claim 28, further comprising a rotor or traveler configured to be advanced by the transmission element, the rotor or traveler thereby charging the mechanical energy storage element.

30. The drive unit of claim 29, further comprising a nonreturn element which prevents the rotor or traveler from moving in a reverse direction.

31. The drive unit of claim 30, wherein the nonreturn element comprises a ratchet.

32. The drive unit of claim 28, wherein the transmission element comprises a pivotable lever that is engageable by the actuator.

33. The drive unit of claim 32, further comprising a rotor or traveler disposed between the pivotable lever and the mechanical energy storage element, the pivotable lever advancing the rotor or traveler as the pivotable lever oscillates.

34. The drive unit of claim 33, wherein the pivotable lever comprises first and second level arms, the first lever arm being engaged by the actuator and the second level arm engaging the rotor or traveler, the second lever arm being longer than the first lever arm, whereby the pivotable lever amplifies the travel strokes from the actuator.

35. The drive unit of claim 28, wherein the mechanical energy storage element comprises a spring.

36. The drive unit of claim 28, further comprising a movement element that is driven by the mechanical energy storage element.

37. The drive unit of claim 36, wherein the movement element comprises an output shaft.

38. The drive unit of claim 36, wherein the movement element comprises a plunger configured for pushing a medical consumable from a magazine.

39. The drive unit of claim 36, wherein the movement element comprises a pump for pumping a medically active substance.

40. A drive unit for a medical device, comprising:

an actuator;

a mechanical energy storage element;

a rotor or traveler operably connected to the mechanical energy storage element,

a nonreturn element that prevents a reverse movement of the rotor or traveler; and

a pivotable lever disposed between the actuator and the rotor or traveler, the pivotable lever being configured to transmit movement of the actuator into an advancing movement of the rotor or traveler which thereby charges the mechanical energy storage element.

41. The drive unit of claim 40, wherein the actuator oscillates the pivotable lever.

42. The drive unit of claim 41, wherein the pivotable lever comprises a first lever arm that is engageable by the actuator and a second lever arm that engages the rotor or traveler.

43. The drive unit of claim 42, wherein the second lever arm is longer than the first lever arm, whereby the pivotable lever amplifies the oscillations.

44. The drive unit of claim 40, wherein the nonreturn element comprises a ratchet.

45. The drive unit of claim 40, wherein the mechanical energy storage element comprises a spring.

46. The drive unit of claim 40, further comprising a movement element that is driven by the mechanical energy storage element.

47. The drive unit of claim 46, wherein the movement element comprises an output shaft.

48. The drive unit of claim 46, wherein the movement element comprises a plunger configured for pushing a medical consumable from a magazine.

49. The drive unit of claim 46, wherein the movement element comprises a pump for pumping a medically active substance.

50. A method of actuating a drive unit in a medical device, comprising:

oscillating a step-up element with an actuator;

converting the oscillation of the step-up element into an advancing movement of a rotor or traveler while preventing reverse movement of the rotor or traveler;

converting at least a portion of the advancing movement of the rotor or traveler into energy stored by a mechanical energy storage element; and

releasing the energy in the mechanical energy storage element to actuate the medical device.

51. The method of claim 50, wherein the medical device comprises a lancet system and the releasing of the energy in the mechanical energy storage element comprises driving a lancet of the lancet system in a puncturing direction.

52. The method of claim 50, wherein the releasing of the energy in the mechanical energy storage element comprises transporting medical consumables.

53. The method of claim 50, wherein the releasing of the energy in the mechanical energy storage element comprises driving a pump to convey a medical substance from a container.

54. The method of claim 50, wherein the releasing of the energy in the mechanical energy storage element comprises driving an insulin pump for conveying insulin from an exchangeable ampoule.

56. The method of claim 50, wherein the mechanical energy storage element comprises a spring and the step of releasing the energy in the mechanical energy storage element comprises discharging the spring.

57. The method of claim 56, wherein the medical device comprises a lancet system and the discharging of the spring comprises driving a lancet of the lancet system in a puncturing direction.