Micropump

• US 20090123309A1
• Filed: 12/08/2006
• Published: 05/14/2009
• Est. Priority Date: 12/28/2005
• Status: Active Grant

• Current Assignee: Sensile Medical AG (Gerresheimer AG)
• Original Assignee: Sensile Pat Ag
• Inventors: Hilber, Josef, Straessler, Sigfrid
• Granted Patent: US 8,282,366 B2
• Time in Patent Office: Days
• US Class Current: 417/417
• CPC Class Codes: A61M 2005/14252 with needle insertion means
• CPC Class Codes: A61M 2205/103 rotating
• CPC Class Codes: A61M 2205/8287 operated by an external magnetic or electromagnetic field
• CPC Class Codes: A61M 5/1413 Modular systems comprising interconnecting elements
• CPC Class Codes: A61M 5/14216 Reciprocating piston type
• CPC Class Codes: A61M 5/14236 Screw, impeller or centrifugal type pumps
• CPC Class Codes: A61M 5/14244 adapted to be carried by the patient, e.g. portable on the body
• CPC Class Codes: A61M 5/14248 of the skin patch type
• CPC Class Codes: F04B 19/006 Micropumps F04B43/043 and F04B43/095 take precedence
• CPC Class Codes: F04B 51/00 Testing machines, pumps, or pumping installations
• CPC Class Codes: F04B 7/06 the pistons and cylinders being relatively reciprocated and rotated
• CPC Class Codes: F04B 9/042 the means being cams

Abstract

A pump including a stator, a rotor comprising an axial extension slidably and rotatably mounted at least partially in a rotor chamber of the stator, and at least first and second valves between an inlet and the rotor chamber, respectively between the rotor chamber and an outlet, that open and close as, a function of at least the angular displacement of the rotor. The pump comprises interacting cam elements on the rotor and stator and biasing means acting on the rotor for applying a force on the rotor in the axial direction of the stator cam element.

Claims

1-21. -21. (canceled)

22. A pump including a stator, a rotor comprising an axial extension slidably and rotatably mounted at least partially in a rotor chamber of the stator, and at least first and second valves between an inlet and the rotor chamber, respectively between the rotor chamber and an outlet, that open and close as a function of at least the angular displacement of the rotor, the pump further comprising interacting cam elements on the rotor and stator and biasing means acting on the rotor for applying a force on the rotor in the axial direction of the stator cam element, the cam elements being configured such that they are separated by a certain axial distance h at a specified angular position when both valves are closed.

23. The pump according to claim 22, wherein the rotor comprises at least first and second axial extensions having different diameters, and first and second seals mounted around the first and second axial extensions, the axial extensions being provided with liquid supply channels cooperating with the respective first and second seals to create first and second valves that open and close liquid communication across the respective seal as a function of at least the angular displacement of the rotor.

24. The pump according to claim 23, wherein the cam elements comprise abutment shoulders engageable upon reverse rotation of the rotor in order to define an angular reference position of the rotor relative to the stator.

25. The pump according to claim 22, wherein the cam element provided around the stator is in the form of a protrusion and the cam element on the rotor is provided on a motor portion from which the axial extensions extend, the rotor cam element comprising a camming surface extending along an arc and of varying axial height as a function of the angular position.

26. The pump according to claim 22, wherein the biasing means comprises a spring attached to the stator, pressing on the rotor.

27. The pump according to claim 22, wherein the inlet of the pump is situated at an end of the first axial rotor extension.

28. The pump according to claim 27, wherein a housing portion defining the pump inlet is integrally formed with a reservoir for containing the liquid to be pumped.

29. The pump according to claim 23, wherein the first and second seals are formed as a single integral sealing element.

30. The pump according to claim 23, further comprising a third seal mounted around the second axial extension proximate the motor portion of the rotor, delimiting an outlet portion of the rotor chamber.

31. The pump according to claim 23, wherein the seals are injection molded with at least a part of the stator housing.

41. A patch pump device comprising a disposable unit including a reservoir and a pump according to claim 22 mounted to the reservoir.

42. The patch pump device according to claim 41, further comprising an adhesive base adapted for adhesive mounting of the patch pump on a patient'"'"'s skin.

43. The patch pump device according to claim 41, further comprising a catheter in communication with an outlet of the pump and adapted for subcutaneous drug administration.

44. The patch pump device according to claim 41, further comprising a reusable base unit comprising a drive for driving the pump rotor, the base unit being removably mounted to the disposable unit.

32. A pump including a rotor comprising a motor portion, first and second axial extensions having different diameters extending therefrom, a stator comprising a stator housing having a rotor chamber for receiving at least the axial extensions therein, and first and second seals mounted around the first and second axial extensions, the axial extensions being provided with liquid supply channels cooperating with the respective first and second seals to create first and second valves that open and close liquid communication across the respective seal as a function of at least the angular displacement of the rotor, wherein the pump comprises a third seal mounted around the second axial extension proximate the motor portion of the rotor, delimiting an outlet portion of the rotor chamber.

33. The pump according to claim 32, comprising interacting cam elements on the rotor and stator and biasing means acting on the rotor for applying a force on the rotor in the axial direction of the stator cam element, the cam elements being configured such that they are separated by a certain axial distance h at a specified angular position when both valves are closed.

34. The pump according to claim 33, wherein the cam elements comprise abutment shoulders engageable upon reverse rotation of the rotor in order to define an angular reference position of the rotor relative to the stator.

35. The pump according to claim 33, wherein the cam element provided around the stator is in the form of a protrusion and the cam element on the rotor is provided on a motor portion from which the axial extensions extend, the rotor cam element comprising a camming surface extending along an arc and of varying axial height as a function of the angular position.

36. The pump according to claim 33, wherein the biasing means comprises a spring attached to the stator, pressing on the rotor.

37. The pump according to claim 32, wherein an inlet of the pump is situated at an end of the first axial extension of the rotor.

39. The pump according to claim 32, wherein the first and second seals are formed as a single integral sealing element.

40. The pump according to claim 32, wherein the seals are injection molded with at least a part of the stator housing.

45. A patch pump device comprising a disposable unit including a reservoir and a pump according to claim 32 mounted to the reservoir.

46. The patch pump device according to claim 45, further comprising an adhesive base adapted for adhesive mounting of the patch pump on a patient'"'"'s skin.

47. The patch pump device according to claim 45, further comprising a catheter in communication with an outlet of the pump and adapted for subcutaneous drug administration.

48. The patch pump device according to claim 45, further comprising a reusable base unit comprising a drive for driving the pump rotor, the base unit being removably mounted to the disposable unit.

38. The pump according to c aim 37, wherein a housing portion defining a pump inlet is integrally formed with a reservoir for containing the liquid to be pumped.

49. A method of operating a pump including a stator, a rotor comprising an axial extension slidably and rotatably mounted at least partially in a rotor chamber of the stator, and at least first and second valves between an inlet and the rotor chamber, respectively between the rotor chamber and an outlet, that open and close as a function of at least the angular position of the rotor, the method including:

detecting axial displacement of the rotor as a function of the angular position of the rotor; and

comparing the axial displacement detected with an expected displacement value in order to determine if there is a malfunction due to blockage downstream, leakage of a valve, or air in the rotor chamber.

50. The method according to claim 49, to test a malfunction due to the presence of air in the rotor chamber or leakage of either valve, further including:

turning the rotor to a test position where the first and second valves are closed; and

applying a force on the rotor in an axial direction.

51. The method according to claim 50, for operating a pump further comprising interacting cam elements on the rotor and stator and biasing means acting on the rotor for applying a force on the rotor in the axial direction of the stator cam element, the method including:

selecting as the test position a position where the cam elements are separated by a certain axial distance h and both valves are closed.

52. The method according to claim 49, including a step of defining a reference angular position of the rotor relative to the stator by:

turning the rotor one or more cycles in a pumping direction; and

subsequently reversing the rotor rotation until shoulders of the rotor and stator cam elements abut.

53. A method of operating a pump including a stator, a rotor comprising an axial extension slidably and rotatably mounted at least partially in a rotor chamber of the stator, and at least first and second valves between an inlet and the rotor chamber, respectively between the rotor chamber and an outlet, that open and close as a function of at least the angular displacement of the rotor, the pump further comprising interacting cam elements on the rotor and stator and biasing means acting on the rotor for applying a force on the rotor in the axial direction of the stator cam element, the method including:

turning the rotor one or more cycles in a pumping direction; and

subsequently reversing the rotor rotation until shoulders of the rotor and stator cam elements abut in order to define a reference angular position of the rotor relative to the stator.