Multiple stage blowers and volutes therefor
AssigneeResMed Limited
InventorsGeoffrey Daniel Daly, Alexander Virr, Stephen Anthony Lea, Dion Charles Chewe Martin, Nicholas Jerome Reed, Larry Puckeridge, Timothy Tsun-Fai Fu
Life of this patent
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Abstract
A multiple stage 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 multiple stage 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.
Claims39
A blower comprising:
- a motor having opposed ends,
- a first conduit adapted to transport air from an external inlet to an internal inlet, said first conduit having a spiral shape, the internal inlet being positioned on one end of the motor and the external inlet being positioned on the opposite end of the motor,
- stationary flow guidance vanes positioned between the first conduit and the internal inlet, said stationary flow guidance vanes being adapted to change direction of gas arriving at the vanes from primarily tangential to primarily radial,
- a second conduit adapted to transport air from said internal inlet to an external outlet.
An enclosure for a blower used in the administration of positive pressure ventilation of a patient, the enclosure including:
- an enclosure base defining a blower chamber for the blower and a primary muffling chamber upstream of the blower chamber;
- an enclosure lid provided to sealingly engage the enclosure base;
- and
- a flow meter provided upstream of the blower chamber and the primary muffling chamber.
An enclosure for a blower used in the administration of positive pressure ventilation of a patient, the enclosure including:
- an enclosure base defining a blower chamber for the blower;
- an enclosure lid provided to sealingly engage the enclosure base;
- a flow meter provided upstream of the blower chamber;
- and
- an inlet connector provided to an inlet side of the flow meter,
- wherein the inlet connector includes an upwardly sloping portion positioned below the inlet side of the flow meter.
A blower comprising:
- a motor provided with opposed first and second shafts;
- first and second stage impellers associated with respective first and second intakes, provided to the first and second shafts, respectively, wherein the second intake of the second stage impeller is positioned between the first and second stage impellers;
- an inner casing to support the motor;
- an outer casing to support the inner casing;
- a substantially annular channel is provided between the inner and outer casings, wherein, in operation, gas is directed from the first stage impeller towards the second stage impeller via the substantially annular channel.
Dependencies are inferred from the claim text.