Flow diverter for controlling the pressure and flow rate in a CPAP device

• US 6,895,964 B2
• Filed: 04/27/2004
• Issued: 05/24/2005
• Est. Priority Date: 01/08/2002
• Status: Active Grant

• Current Assignee: ResMed Pty Ltd. (ResMed Incorporated)
• Original Assignee: Resmed Limited (ResMed Incorporated)
• Inventors: McAuliffe, Patrick J., Bullock, Denis L.
• Primary Examiner(s): Bennett, Henry
• Assistant Examiner(s): MITCHELL, TEENA KAY
• Application Number:
  US10/832,259
• Publication Number:
  US 20040194783A1
• Time in Patent Office: 392 Days
• Field of Search: 128/200.24, 128/204.18, 128/204.22, 128/204.21, 128/204.23, 128/204.24, 128/204.25, 128/204.26, 128/205.25, 128/201.28, 137/162, 137/625, 137/625.12, 137/625.14, 137/487.5
• US Class Current: 128/205.24
• CPC Class Codes: A61M 16/0066 Blowers or centrifugal pumps
• CPC Class Codes: A61M 16/0069 the speed thereof being controlled by respiratory parameters, e.g. by inhalation
• CPC Class Codes: A61M 16/024 including calculation means, e.g. using a processor
• CPC Class Codes: A61M 16/06 Respiratory or anaesthetic masks
• CPC Class Codes: A61M 16/0866 Passive resistors therefor
• CPC Class Codes: A61M 16/20 Valves specially adapted to medical respiratory devices
• CPC Class Codes: A61M 16/202 electrically actuated
• CPC Class Codes: A61M 2016/0039 in the inspiratory circuit
• CPC Class Codes: A61M 2205/42 Reducing noise
• CPC Class Codes: F16K 11/0525 the closure members being pivoted around an essentially central axis
• CPC Class Codes: Y10T 137/86525 Flow combining with flow dividing

Abstract

A flow diverter valve is used in controlling the pressure and/or flow rate of a breathable gas supplied to the airways of a patient by a breathable gas flow generator supply apparatus during, for example, ventilatory assistance treatments such as non-invasive positive pressure ventilation and nasal Continuous Positive Airway Pressure (CPAP) treatment of Obstructive Sleep Apnea. The flow diverter valve includes a vane and a housing. The housing has an inlet port, an outlet port, and an exhaust port. The exhaust port opens to atmosphere, and the inlet port is in fluid communication with the flow generator. The outlet port is in fluid communication with a patient mask via a conduit. The vane is configured with respect to the housing such that a blower associated with the CPAP apparatus remains substantially unchoked, regardless of whether the vane is in the open or closed position.

Claims

1. A valve assembly for use in a ventilator, the valve assembly comprising a housing and a rotatable vane for directing the flow of air within the housing,

the housing having an inlet port for receiving a flow of pressurized air from a blower, an outlet port for delivering air to a patient interface and an exhaust port,

the vane being rotatable between a first angular position and a second angular position without choking the blower, wherein:

(i) in the first angular position substantially all of the flow of air received at the inlet port is directed by the vane to the exhaust port,

(ii) in the second angular position substantially all of the flow of air received at the inlet port is directed by the vane to the outlet port, and

(iii) in angular positions intermediate of the first and second angular positions, a fraction of the flow of air received at the inlet port is directed by the vane to the exhaust port and the complementary fraction of the flow of air received at the inlet port is directed by the vane to the outlet port.

2. The valve assembly of claim 1, wherein the vane forms a portion of a passageway between the inlet port and the outlet port when in the second angular position.

3. The valve assembly of claim 1, wherein the vane can selectively direct undiverted flow from the inlet port to at least one of the exhaust port and the outlet port when the vane is between the first angular position and the second angular position.

4. A ventilatory assistance apparatus, comprising:

a flow generator; and

a flow diverter valve in communication with the flow generator, the flow diverter valve including a housing defining an inlet port, an outlet port and an exhaust port positioned between the inlet port and the outlet port and configured to exhaust at least one of flow from the inlet port and back flow from the outlet port, and a vane moveable between an open position and a closed position, wherein;

the vane can selectively protrude into the flow from the inlet port and thereby variably divert the flow from the inlet port to at least one of the exhaust port and the outlet port, and the vane forms a portion of a passage leading to the outlet port when in the closed position.

5. The apparatus of claim 4, further comprising an apparatus body including a side wall with an opening aligned with the exhaust port.

6. The apparatus of claim 4, wherein the flow generator includes a blower that remains substantially unchoked as the vane moves between the open position and the closed position.

7. A flow diverter valve, comprising:

a housing defining an inlet port and an outlet port;

an exhaust port positioned between the inlet and outlet ports; and

a vane moveable between an open position and a closed position, wherein;

the vane can selectively protrude into the flow from the inlet port and thereby variably divert the flow from the inlet port to at least one of the exhaust port and the outlet port, and

the vane forms a portion of a passage leading to the outlet port when in the closed position.

8. The flow diverter valve of claim 7, wherein the housing includes a straight inlet port flow path from the inlet port to the exhaust port directing a majority of undiverted flow from the inlet port to the exhaust port.

9. A CPAP apparatus, comprising:

a flow generator; and

a flow diverter valve in communication with the flow generator, the flow diverter valve including a housing defining an inlet port, an outlet port and an exhaust port positioned between the inlet port and the outlet port and configured to exhaust at least one of flow from the inlet port and back flow from the outlet port, and a vane moveable between an open position and a closed position, wherein the vane can selectively admit undiverted flow from the inlet port to at least one of the exhaust port and the outlet port when the vane is in the open position.

10. The apparatus of claim 9, wherein the flow generator includes a blower that remains substantially unchoked as the vane moves between the open position and the closed position.

11. A flow diverter valve, comprising:

a housing defining an inlet port and an outlet port;

an exhaust port positioned between the inlet and outlet ports; and

a vane moveable between an open position and a closed position, wherein the vane can selectively admit undiverted flow from the inlet port to at least one of the exhaust port and the outlet port when the vane is in the open position.

12. The flow diverter valve of claim 11, wherein flow capacity of the housing downstream of the vane is at least substantially equal to flow capacity upstream of the vane, regardless of whether the vane is in the open position or the closed position.