Double-ended blower and volutes therefor

• US 20070134085A1
• Filed: 02/09/2007
• Published: 06/14/2007
• Est. Priority Date: 12/10/2001
• Status: Active Grant

• Current Assignee: ResMed Pty Ltd. (ResMed Incorporated)
• Original Assignee: Resmed Limited (ResMed Incorporated)
• Inventors: Virr, Alexander, Puckeridge, Larry, Daly, Geoffrey, Lea, Stephen, Martin, Dion Charles, Reed, Nicholas, Fu, Timothy
• Granted Patent: US 8,225,786 B2
• Time in Patent Office: Days
• US Class Current: 415/198.100
• CPC Class Codes: A61M 16/0057 Pumps therefor
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/0816 Joints or connectors
• CPC Class Codes: A61M 16/0875 Connecting tubes
• CPC Class Codes: F04D 1/00 Radial-flow pumps, e.g. centrifugal pumps; Helico-centrifugal pumps adapted for pumping specific fluids F04D7/00; priming or boosting F04D9/00
• CPC Class Codes: F04D 17/12 Multi-stage pumps
• CPC Class Codes: F04D 17/122 the individual rotor discs being, one for each stage, on a common shaft and axially spaced, e.g. conventional centrifugal multi- stage compressors
• CPC Class Codes: F04D 17/164 Multi-stage fans, e.g. for vacuum cleaners
• CPC Class Codes: F04D 25/166 using fans
• CPC Class Codes: F04D 27/004 by varying driving speed
• CPC Class Codes: F04D 29/582 specially adapted for elastic fluid pumps
• CPC Class Codes: Y02B 30/70 Efficient control or regulation technologies, e.g. for control of refrigerant flow, motor or heating

Abstract

A variable speed blower for Continuous Positive Airway Pressure (CPAP) ventilation of patients includes two impellers in the gas flow path that cooperatively pressurize gas to desired pressure and flow characteristics. Thus, the blower can provide faster pressure response and desired flow characteristics over a narrower range of motor speeds, resulting in greater reliability and less acoustic noise.

Claims

1. A CPAP/NIPPV apparatus for treatment of a patient with a sleeping disorder, the apparatus including a blower comprising:

a gas flow path between a gas inlet and a gas outlet;

a motor;

a shaft in communication with the motor, the shaft including first and second shaft portions defining a rotational axis;

a first impeller coupled to the first shaft portion, the first impeller including a first gas intake; and

a second impeller coupled to the second shaft portion, the second impeller including a second gas intake, said impellers being disposed between the gas inlet and the gas outlet to cooperatively pressurize gas flowing from said gas inlet to said gas outlet.

2. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the second gas intake surrounds the second shaft portion and is positioned along said axis between the first and second impellers.

3. A CPAP/NIPPV apparatus as claimed in claim 1, further comprising a housing to support the motor and to at least partially define the gas path adjacent to the motor to guide gas from the first impeller to the second impeller.

4. A CPAP/NIPPV apparatus as claimed in claim 3, wherein the housing comprises first and second casing halves that are fastened to one another.

5. A CPAP/NIPPV apparatus as claimed in claim 3, wherein an internal surface of the housing at least partially defines the gas path.

6. A CPAP/NIPPV apparatus as claimed in claim 5, wherein the internal surface of the housing is formed adjacent a motor stator of the motor so as to define the gas path between the motor stator and the internal surface.

7. A CPAP/NIPPV apparatus as claimed in claim 1, further comprising a damping sleeve.

8. A CPAP/NIPPV apparatus as claimed in claim 7, wherein the damping sleeve comprises first and second halves.

9. A CPAP/NIPPV apparatus as claimed in claim 7, wherein the damping sleeve is made of silicone, foam, rubber and/or polyurethane.

10. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the gas path is defined in part by a spiral path from the first impeller to the second impeller.

11. A CPAP/NIPPV apparatus as claimed in claim 1, wherein each impeller comprises scalloped edges.

12. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the first impeller is configured for rotation within a first volute defined adjacent a first end of the housing.

13. A CPAP/NIPPV apparatus as claimed in claim 1, further comprising a first endcap adjacent the first impeller and a second endcap adjacent the second impeller, wherein said gas path is at least partially defined between the first and second endcaps.

14. A CPAP/NIPPV apparatus as claimed in claim 13, wherein the first endcap includes the first gas intake in the form of a central inlet aperture leading to the first impeller.

15. A CPAP/NIPPV apparatus as claimed in claim 3, wherein the housing comprises the outlet to direct the gas along a path that is substantially tangential to the second impeller.

16. A CPAP/NIPPV apparatus as claimed in claim 13, wherein the first endcap and a portion of a motor stator of the motor define the first volute.

17. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the second impeller is configured for rotation within a second volute.

18. A CPAP/NIPPV apparatus as claimed in claim 17, wherein the second volute is defined between a contoured plate provided to the motor stator and an inside surface of the second endcap.

19. A CPAP/NIPPV apparatus as claimed in claim 3, wherein the housing is made of aluminum.

20. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the first and second impellers are configured for rotation in the same direction.

21. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the first and second impellers are configured for rotation in opposite directions.

22. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the first and second impellers comprise blades configured to direct the gas in a common direction.

23. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the first and second impellers comprise blades configured to direct the gas in opposite directions.

24. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the motor is driven to achieve the desired IPAP (inspiratory positive airway pressure) and EPAP (expiratory positive airway pressure) pressures.

25. A CPAP/NIPPV apparatus as claimed in claim 1, further comprising a patient interface including a mask.

26. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the CPAP/NIPPV apparatus is pre-set to deliver inspiratory positive airway pressure (IPAP) during the inspiratory phase of the patient'"'"'s breathing cycle, and to deliver expiratory positive airway pressure (EPAP) during the expiration of the patient'"'"'s respiratory cycle.

27. A CPAP/NIPPV apparatus as claimed in claim 26, wherein the IPAP is greater than the EPAP.

28. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the blower is configured to generate pressures in the range of about 4 cm H₂O to 28 cm H₂O at flow rates of up to of about 180 L/min as measured at a patient interface.

29. A CPAP/NIPPV apparatus as claimed in claim 1, wherein the first and second shaft portions extend from opposed sides of the motor.