Compact low noise efficient blower for cpap devices

(Cross-reference to application) The present application claims the benefit of Australian Provisional Patent Application No. 2006902781 filed May 24, 2006, which is incorporated herein by reference in its entirety.

The present invention relates to an efficient, low noise, compact blower. This blower can be used in a variety of devices, including medical, cleaning, automotive or computer devices. This blower can also be used as an extractor or suction device. In one embodiment, the blower can be used in non-invasive ventilation (NIVV) devices such as CPAP or ventilation devices.

OSA Nasal CPAP Treatment Treatment of obstructive sleep apnea syndrome (OSA) with continuous positive airway pressure (CPAP) was invented by Sullivan. Please refer to Patent Document 1. Devices that treat OSA typically include a blower that provides a supply of air or a gas suitable for breathing to a patient-side connecting device, such as a mask, by means of an air conduit. Typically, the patient sleeps while wearing the device, so it is desirable to have a system that is quiet and comfortable.

General blower / air pump Blowers are typically classified as centrifugal, axial or mixed flow. In general, a blower comprises two main components: a rotating component, an impeller and a shaft, and a fixed component that defines a fluid flow path, which is typically a chamber such as a vortex chamber. The rotation of the impeller gives kinetic energy to the air. The fixing component directs the air released from the impeller back into the enclosed outlet passage. During this redirection, resistance to flow occurs due to downstream resistance or pressure generated by the downstream pressure source. As the flow slows down against this resistance, some of the kinetic energy is converted into potential energy in the form of pressure.

In general, the faster the impeller is rotated, the higher the pressure will be. A less effective blower must rotate its impeller faster in order to generate the same pressure as a more effective blower. In general, operating a given blower at a lower speed makes the blower quieter and extends its life. Therefore, it is generally desired to make the blower more effective in generating a positive pressure air supply.

With reference to FIGS. 1 and 2, three directions are defined: radial R, tangential T, and axial A. The prior art centrifugal blower 10 includes an outlet 20, an inlet 30, an electric motor 40, an impeller 50, and a shaft 60. Arrow 70 indicates the approximate direction of the airflow. Air enters the blower at inlet 30 and is accelerated by a rotating impeller. The rotation given by the impeller generally directs the airflow in the tangential direction T. The vortex chamber then constrains the air flow, causing the vortex chamber to spiral. Next, the air flow exits the blower approximately in the tangential direction T through the outlet 20.

In some blowers, such as axially deployed vortex chamber blowers, the geometry of the vortex chamber causes the tangential spiral airflow to be slightly before leaving the blower approximately in the tangential direction T. Axial direction A.

Blower performance is often described using a fan curve that indicates air flow velocity vs. air outlet pressure. Many factors affect the curve of the fan, including the diameter of the impeller and the number and shape of the impeller blades. The design process is a complex balance between opposing properties such as desired pressure, flow velocity, size, reliability, manufacturability, and noise. Many combinations of component sizes, shapes and configurations can result in a flow of pressurized air, but such results can be far from optimal or impractical.

ResMed Axial Vortex Chamber Configuration Another form of known blower configuration is described in ResMed's Patent Document 2, whose contents are expressly incorporated herein by reference. As described in this patent application, the geometry of the vortex chamber develops approximately axially, but air exits the blower approximately tangentially.

Respironics ventilator Patent Document 3 of Respironics describes a medical ventilator preferably having a blower assembly comprising three rotating impellers and two stationary stators. In this device, a conventional vortex chamber configuration is used so that air exits the blower assembly approximately tangentially.

The disadvantage of this blower configuration is that it is susceptible to the emission of blade-passing noise.

Respironics REMstar Another known blower can be found in the Respironics REMstar series of CPAP devices. In this device, the air exits the blower approximately tangentially.

ResMed blower Patent Document 4, transferred to ResMed, provides continuous positive airway pressure (CPAP) ventilation for patients, including two impellers in a gas flow path that coordinately pressurize the gas to the desired pressure and flow properties. A double-ended continuously variable transmission blower for this purpose will be described. The contents of this patent are expressly incorporated herein by reference. In this device, the air exits the blower approximately tangentially.

Patent Document 5 and Patent Document 6 describe a multi-stage blower. The contents of both PCT applications are incorporated herein by reference.

As mentioned above, known CPAP and VPAP blowers use a more or less conventional vortex chamber configuration, that is, one in which air exits the vortex chamber tangentially. These configurations have the disadvantage that the asymmetric shape of the vortex chamber leads to an asymmetric flow pattern in the vortex chamber and impeller. This problem is particularly significant at flow velocities that deviate from the ideal "design" flow velocities for vortex chambers. Unfortunately, CPAPs and VPAPs are used under non-ideal flow conditions for a significant portion of their operating time as a result of very large fluctuations in flow requirements. This means that the flow patterns in the vortex chamber and, as a result, in the impeller are very asymmetric, non-uniform and even unstable. This leads to pressurization of the pulse and turbulence. As a result, audible blade passing noise and turbulent noise are generated.

<p num="0016"><patcit num="1"><text>U.S. Pat. No. 4,944,310</text></patcit><patcit num="2"><text>International Publication No. 99/64747 Pamphlet</text></patcit><patcit num="3"><text>International Publication No. 99/13932 Pamphlet</text></patcit><patcit num="4"><text>U.S. Pat. No. 6,910,483</text></patcit><patcit num="5"><text>PCT / AU2006 / 001617</text></patcit><patcit num="6"><text>PCT / AU2006 / 001616</text></patcit><patcit num="7"><text>US Provisional Patent Application No. 60 / 853,778</text></patcit></p>

<p num="0017"> A first aspect of the present invention relates to a breathing apparatus that quietly and effectively provides air supply at positive pressure. Another aspect of the invention is to provide a blower for NIVV devices used in the treatment of various respiratory diseases. Another aspect of the invention is to achieve high pressure delivery for a given motor speed. Another aspect of the invention is a blower capable of supplying a given pressure at relatively low motor speeds and fast response times. Another aspect of the present invention is a blower having a low vane-passing noise emission and / or a turbulent noise emission.</p><p num="0018"> In one embodiment of the invention suitable for a breathing apparatus, the blower is 2 cmH.₂O to 100 cmH₂It is configured to provide pressurized air in the range of O. In another form suitable for the treatment of sleep apnea, the blower is 2 cmH₂30 cmH from O₂It is configured to give pressure in the range of O.</p><p num="0019"> In one form, the blower is configured to provide air at a flow rate of up to 200 L / min. In one form, the blower is configured to provide air at a flow rate ranging from -50 L / min to + 200 L / min.</p><p num="0020"> In one embodiment of the invention suitable for a breathing apparatus, the blower comprises at least one impeller that is relatively small, eg, having a diameter in the range of 20 mm to 200 mm. In one embodiment, the impeller comprises two different sized enclosures to provide a rigid impeller with relatively low inertia. The impeller may be injection molded from a plastic such as polycarbonate or polypropylene.</p><p num="0021"> Aspect of the present invention is that the fixed portion of the blower defines an air flow path that is quiet and efficient. In one embodiment, the fixed portion defines a substantially axially symmetrical air flow path.</p><p num="0022"> One aspect of the invention has a fixed portion or vortex chamber configuration that is substantially axially symmetrical at all stages. Therefore, regardless of the flow velocity, the pattern of air supply by the passage of the impeller blades and in the vortex chamber remains symmetrical and stable. This leads to weaker pressure pulses and less turbulence, which also lowers the level of sonic vane-passing noise and lowers the level of turbulent noise.</p><p num="0023"> In one form, the blower has one stage. In another aspect of the invention, the blower has two or more stages. In the embodiment of the invention in which multiple stages are used along the axis, the motor may be centrally located and a similar number of impellers may be located on either side of the motor along the axis.</p><p num="0024"> In one embodiment, the fixed component of the blower comprises a wing structure that receives airflow from the impeller and directs the airflow in the radial direction. In one embodiment, the blower has a shield placed between the impeller and the wing structure to direct the airflow towards the inlet vane in a direction that is favorable to minimize loss and turbulence. Including. In one embodiment, the airflow is directed axially between the impeller and the wing structure. In one embodiment, the shield also provides a barrier between the impeller blade and the front edge of the blade so that the pressure pulse on the impeller blade is substantially isolated from the blade.</p><p num="0025"> Another aspect of the invention is a step of providing air to the blower through an inlet aligned axially with the axis of the blower, a step of directing air through one or more stages of the blower, and an inlet. It relates to a method of supplying positive pressure air to a patient for treatment, comprising supplying positive pressure air through axially aligned outlets.</p><p num="0026"> Another aspect of the invention is a blower that supplies air at positive pressure, including a fixed portion including an inlet and an outlet, a rotating portion provided on the fixed portion, and a motor configured to drive the rotating portion. Regarding. The fixed portion includes a shield that insulates the stationary blade of the fixed portion from the blades of the impeller of the rotating portion. The shield includes a tubular portion having an inner surface and an outer surface. The inner surface is configured to support the bearing of the rotating part and the outer surface is configured to support the stator assembly of the motor.</p><p num="0027"> Other aspects, features and advantages of the invention are part of this disclosure and will become apparent from the following detailed description, when taken up as an example in conjunction with the accompanying drawings showing the principles of the invention. Let's go.</p><p num="0028"> The accompanying drawings facilitate understanding of various embodiments of the present invention.</p>

<figref num="1">It is a top view of the blower assembly of a general prior art.</figref><figref num="2">It is an elevation view of the general prior art blower assembly shown in FIG.</figref><figref num="3a">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="3b">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="3c">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="3d">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="3e">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="3f">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="3g">It is a figure of the blower by one Embodiment of this invention.</figref><figref num="4a">It is an exploded view of the blower shown in FIGS. 3a-3g.</figref><figref num="4b">It is an exploded view of the blower shown in FIGS. 3a-3g.</figref><figref num="4c">It is an exploded view of the blower shown in FIGS. 3a-3g.</figref><figref num="5a">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="5b">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="5c">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="5d">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="5e">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="5f">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="5g">It is a figure of the blower shown in FIGS. 3a-3g.</figref><figref num="6a">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="6b">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="6c">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="6d">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="6e">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="6f">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="6g">It is a figure of the impeller by one Embodiment of this invention.</figref><figref num="7a">It is a figure of the stator component by one Embodiment of this invention.</figref><figref num="7b">It is a figure of the stator component by one Embodiment of this invention.</figref><figref num="7c">It is a figure of the stator component by one Embodiment of this invention.</figref><figref num="7d">It is a figure of the stator component by one Embodiment of this invention.</figref><figref num="8a">It is a figure of the shielding part by one Embodiment of this invention.</figref><figref num="8b">It is a figure of the shielding part by one Embodiment of this invention.</figref><figref num="8c">It is a figure of the shielding part by one Embodiment of this invention.</figref><figref num="9">It is a figure of the impeller with two enclosures according to the alternative embodiment of this invention.</figref><figref num="10a">It is a figure of the alternative stator component by the alternative embodiment of this invention.</figref><figref num="10b">It is a figure of the alternative stator component by the alternative embodiment of this invention.</figref><figref num="11">It is a figure of the blower by another embodiment of this invention.</figref><figref num="12">It is a figure of the blower by another embodiment of this invention.</figref><figref num="13">It is a figure of the blower by another embodiment of this invention.</figref><figref num="14">It is a figure of the blower by another embodiment of this invention.</figref><figref num="15">It is an exploded view of the blower shown in FIGS. 11-14.</figref><figref num="16">It is sectional drawing of the blower shown in FIGS. 11-14.</figref><figref num="17">It is sectional drawing which shows the support system for a blower by one Embodiment of this invention.</figref><figref num="18">It is sectional drawing of the blower by another embodiment of this invention.</figref><figref num="19">It is sectional drawing of the blower by another embodiment of this invention.</figref>

Hereinafter, embodiments of the present invention will be described in detail.

Aspects of the invention are described herein in applications for non-invasive ventilation (NIVV) treatment devices such as CPAP, mechanical ventilation and assisted breathing (eg, airway positive pressure (PAP) devices or flow generators). However, a feature of the present invention is that it has applications for other applications in which blowers are used, such as vacuum cleaners, computer cooling devices, and HVAC devices such as those found in buildings and vehicles. I want to be understood.

As used herein, the terms "air pump" and "blower" may be used interchangeably. In the present specification, the phrase "fixed part" is construed to include "vortex chamber". The term "air" is construed to include a gas suitable for breathing (eg, air with additional oxygen). It is also acknowledged that the blowers described herein can be configured to deliver fluids other than air.

As used herein, the word "comprising" should be understood to mean its "open", that is, "including", and therefore its "closed". It should be understood that it is not limited to the meaning of "consisting only of". The corresponding meanings are attributed to the corresponding words "comprise", "comprised", and "comprises" at the position where the word appears.

Although specific embodiments of the invention have been described, it will be apparent to those skilled in the art that the invention can be embodied in other specific embodiments without departing from the essential features of the invention. There will be. Therefore, embodiments and examples of the invention should be considered exemplary and not limiting in all respects, and the scope of the invention is attached rather than the examples or description described above. The meaning of the claims and all modifications within the scope of the claims are therefore intended to be incorporated into the present invention. All references herein to known prior art do not acknowledge that such prior art is generally known to those skilled in the art to which aspects of the invention are involved, unless otherwise indicated. I want you to understand that further.

1. Overall description The blower 100 according to an embodiment of the present invention may be in the form of a centrifugal air pump including a fixed portion, a rotating portion, and an electric motor.

In the exemplary embodiment shown in FIGS. 3a-5g, the fixtures are the outer enclosure 170 of the two parts 172, 174 and the three sets of stator components 180, 182, 184 and the two shields 190, 192. Includes an assembly of internal flow guidance components including. The rotating part comprises three impellers 150, 152, 154 and a shaft 160 configured to be driven by an electric motor 140. In one embodiment, the electric motor 140 may be a brushless DC motor. In the illustrated embodiment, the blower has three stages, each with a corresponding impeller and a set of vanes and shields. As shown in FIGS. 3a-3g and 4a, the blower 100 is generally cylindrical and has an inlet 130 at one end and an outlet 120 at the other end.

In the illustrated embodiment, all components of the blower are aligned along the shaft of the motor, defining an axis in which all components form a substantially symmetrical shape about it. In one embodiment, the blower may be self-similar in a fan shape around its axis. This axial symmetry may be applied to all stages.

An advantage of the blower according to one embodiment of the present invention is that the blower promotes a symmetrical and stable flow pattern in the vortex chamber over the range of pressure and flow velocity encountered during use. In this way, the emission of blade passing noise and turbulent noise is reduced.

The advantage of the illustrated embodiment is the ease of manufacture and assembly provided by the geometry of the components, especially when injection molded, and by the stacked nature of the assembly.

2. Fluid flow path 2.1 First stage The first stage of the blower is described here. As best shown in Figures 4a-4c and 5a-5g, air enters the blower 100 at inlet 130 and passes through the first rotating impeller 150, where the air is tangentially accelerated and radially outward. Be directed. The air then passes around the sides of the motor 140 and has a large tangential velocity component and also an axial component towards the first set of stationary blades 185 of the stator component 180. , Flows in a spiral. In the present embodiment, since the shielding function is provided by the motor case, the shielding portion is not provided in the first stage. In the first set of stationary blades 185, air is directed radially inward towards hole 181 and then to the second stage.

2.2 Second stage In the second stage, as shown in FIGS. 4a-4c and 5a-5g, the air is first accelerated tangentially by the second rotating impeller 152 and also flows radially outward. The air then has a large tangential velocity component and an axial component that passes through the gap 164 defined by the outer edge of the circular disk 190 and the inner surface of the stator component 182. It flows in a spiral. Air then enters a second set of vanes 187 formed within the stator component 182, directed radially inward towards hole 183, and then directed to the third stage.

2.3 3rd stage The fluid flow path of the third stage is the same as that of the fluid flow path of the second stage. As shown in FIGS. 4a-4c and 5a-5g, air enters this stage through the hole 183, is tangentially accelerated by the third rotating impeller 154, and is also directed radially outward. The air then flows spirally with a component of high tangential velocity and an axial component passing through the gap 166 defined by the outer edge of the circular disk 192 and the inner edge of the housing 174. .. The air is then directed towards the outlet 120 by the vanes 184 formed within the housing 174.

3. Fixed part 3.1 Overall The blower fixture includes any external housing components 172, 174, internal flow guide stator components 180, 182, 184, and two shields 190, 192, and is dimensionally stable. It may be made from a material of suitable rigidity or semi-rigidity. In one embodiment, the stator component has one or more properties of good thermal conductivity, relatively low cost, low density, sound buffering properties, and ease of molding that reduces subsequent machining. May be made from a material that results in. The use of thermally conductive materials can also help keep the motor cool and warm the air. The ability to heat air may provide additional benefits to the blowers used in NIVV equipment.

In one embodiment, at least some of the components of the fixed portion may be made from aluminum or an alloy thereof, such as an aluminum die-cast product. In another embodiment, at least some of the components of the fixation may be made from magnesium or an alloy thereof. In yet another embodiment, at least some of the components of the fixed portion may be made from a plastic material.

3.2 Entrance The air inlet 130 is configured to provide sufficient airflow into the blower to ensure that the desired flow requirements are met while preventing excessive noise from being emitted back from the air inlet 130. Also, the dimensions of the air inlet 130 depend on the desired level of flow required by the blower and the particular application. In the NIVV embodiment, the air inlet 130 may have a diameter between 2 mm and 100 mm, for example between 15 mm and 20 mm.

3.3 Stator components Stator components, including the vanes, are constructed to facilitate smooth transitions in the direction of flow. In one embodiment, the two stator components 180, 182 are injection molded from plastic (see, eg, FIGS. 7a-7d). The third stator component includes a vane 184 molded into a bottom casing 174. In another embodiment, the vane may be made using a thermally conductive material such as metal.

3.3.1 Radial flow direction In the NIVV embodiment of the present invention, the vane directs the flow approximately in the radial direction. The blades have a height in the range of 1 mm to 100 mm, for example 3 mm to 5 mm. This configuration helps maintain a small configuration of the blower as a whole when compared to a wing or step-to-step passage that takes the flow approximately at right angles and contains significant axial components.

3.3.2 Shape Each stage has multiple vanes for directing airflow, eg 2 to 100 vanes. In one embodiment, each stage has seven vanes. Each wing is substantially identical and has a generally spiral shape with a radius of curvature at the inner end of the wing that is smaller than the outer end of the wing so that the air is decelerated before it becomes too violent. Has.

In other applications, such as applications where very high flow rates are required and noise is not a major consideration, the air does not have to be decelerated by the vanes.

3.3.3 Direction of mixed axial / radial flow In an alternative embodiment of the invention, the blades may direct the flow to a plane that is perpendicular to the axis, or at least one set of stationary blades directs the flow both radially and axially. , There may be an axial component for the directed flow. In this embodiment, the final stage vane may be placed on an inclined surface or not at a constant height, but deploys axially as well as radially, thereby allowing the air to be more graduated. Can be bent in the direction. For example, FIGS. 10a and 10b show an impeller 250 mounted on a motor shaft 260, a shield 290, and a stator 280 including a vane 285 constructed to direct flow both in the radial and axial directions. Shown. Thus, the wing begins tangentially (as in the embodiment above), but eventually directs the flow axially (rather than radially as in the embodiment above). This configuration occupies a little more space, but can improve the generation of pressure. This configuration means that air does not pass at right angles.

3.4 Shield that insulates the stationary wing Another aspect of the invention relates to a shield (see, eg, FIGS. 8a-8c) located between the vane and the blades of the impeller. In one embodiment, the shield is formed from injection molded plastic, but other suitable materials (such as metal) may be used. In the illustrated embodiment, the shield extends radially beyond the outer edge of the vane. This means that there is no "line of sight" path between the vanes and the impeller blades, resulting in a reliable and uniform circulation of airflow that collides with the vanes. Work for.

As best shown in Figures 5b, 5d and 5e, the shields 190 and 192 direct the flow through the annular openings 164 and 166, respectively. Peripheral openings may also be used. In one form, the shield leaves only a narrow annular gap between its outer edge and the wall of the fixed portion. This gap is sufficient to provide sufficient airflow to the next stage without resulting in excessive pressure drop. In one embodiment of the blower used in the NIVV device, the clearance may be between 0.5 mm and 100 mm, for example between 1 mm and 2 mm. The shield also provides a sound barrier by insulating the pressure pulses of the impeller blades from the vanes.

In one form, the shield is a circular disc, which in NIVV devices may be welded to a vane.

In an alternative embodiment, the shield may rotate. Such a rotating shield may be integrated into the impeller so that the lower enclosure acts as a rotating shield between the impeller blades and the vanes. For example, FIG. 9 shows an impeller 350 mounted on a motor shaft 360. The impeller 350 includes upper and lower enclosures 352, 354 in which the lower enclosure 354 acts as a rotating enclosure between the impeller blades 355 and the vanes 385 of the stator 380.

3.5 exit In contrast to known prior art centrifugal blowers that direct the air exiting the blower approximately tangentially, the centrifugal blower according to one embodiment of the invention directs air approximately axially. This axial symmetry is effective in reducing airflow turbulence and reducing blade-passing noise because the impellers and blades encounter symmetrical flow patterns at all device flow velocities.

3.6 housing The housing includes chamfers on the outer housing that help attach the separate components of the housing together. This configuration allows for smaller packages overall.

The gap between the inner wall of the outer housing and the outer wall of the motor allows air to pass down around the sides of the motor. In one embodiment, the size of the gap is sufficient to prevent significant friction loss, but is not large enough to overstate the overall size of the device. In one embodiment of the blower used in the NIVV device, the size of the gap may be between 0.1 mm and 100 mm, for example about 4 mm.

The ability of air to flow around the motor can help keep the motor cold. Its ability can also help heat the patient's air in the NIVV device.

Four. Rotating part 4.1 Impeller In the NIVV embodiment, the blower comprises a plurality of impellers 150, 152, 154, as shown in FIGS. 4a-4c. In the illustrated embodiment, only the impeller 150 will be described in detail as the impellers are identical in configuration. With particular reference to FIGS. 6a-6g, the Impeller 150 is of an integrally molded plastic structure, but other suitable materials and manufacturing techniques are available. The impeller 150 includes a plurality of continuously curved blades 200 sandwiched between a pair of disc-shaped enclosures 202 and 204. The smaller enclosure 202 incorporates a hub or bush 206 configured to receive the motor shaft 160. The enclosure 202 overlaps the inner portion of the blade 200, i.e., the outer diameter (OD) of the smaller enclosure is substantially smaller than the OD of the larger enclosure 204. The larger enclosure 204 is formed with a relatively large central opening 208 and extends to the radial outer tip of the blade. Making the OD of the smaller enclosure 202 slightly smaller than the diameter of the central opening 208 of the enclosure 204 facilitates the molding process used to manufacture the impeller.

By using different sized enclosures, the inertia of the impeller 150 is reduced while maintaining the overall stiffness of the impeller. In this regard, the impeller 150 may be made of polycarbonate, polypropylene, polyamide, or other material that provides sound buffering properties that buffer the resonance of the impeller. Fiberglass reinforcement may be used to increase the stiffness of any of these materials.

4.1.1 Diameter In NIVV embodiments, the impeller 150 may have a diameter in the range of 20 mm to 200 mm. In one embodiment, the impeller 150 may have a diameter in the range of 40 mm to 50 mm, eg 42 mm. Impellers with diameters in this range can provide a good compromise between the overall dimensions of the blower, the inertia of rotation, and the level of turbulence.

4.1.2 Number of blades In the NIVV embodiment, the impeller has 4 to 100 (eg 11) primary blades 200. The impeller may include secondary and tertiary blades and may have different blade passage cross sections (not shown).

4.1.3 Blade shape In one embodiment, the impeller blades 200 may be continuously curved in the radial direction and may be tapered in width at the radial outer portion. The narrowed width at the tip of the blade can reduce turbulence (for example, the Reynolds number is (in order) less in a blower with three impellers, two impellers, and one impeller). In one embodiment, the outermost lateral edges of the blades are stepped (not shown) along the respective lateral widths of the blades to help reduce turbulent noise at the tips of the blades. ) May be added. In another embodiment, the outermost lateral edge of the blade 200 is flat. In one embodiment, the blade 200 has an outlet height in the range of 1 mm to 40 mm, for example 3 mm to 6 mm. In one form, the blade 200 has an inlet height that is the same as the outlet height, but in other forms the inlet and outlet heights may be different.

The blade 200 has an inlet angle between 0 ° and 90 °, eg, about 20 ° tangent. The blade 200 has an exit angle with respect to the tangent between 70 ° and 110 °, but other angles are possible.

4.2 Shaft In one embodiment, there is a gap between the shaft 160 and the shields 190, 192. This gap is sufficient to allow the shaft to rotate within the shield, but is small enough to prevent significant leakage between the impellers 152, 154 and the internal flow guidance components 182, 184. For blowers for NIVV equipment, the clearance may be less than 10 mm, for example less than 2 mm.

5. Axial symmetry A blower according to an embodiment of the present invention comprises an axially symmetrical vortex chamber using a stationary blade. The air flow enters and exits each stage in the blower substantially axially. As a result, air enters the blower axially at one end and exits the blower axially at the other. The air flow path is substantially axially symmetrical throughout the blower and maintains a constant supply pattern through the impeller and in the vortex chamber. The symmetrical blower provides balance, which in turn lowers the level of passing noise of the blades and lowers the level of turbulent noise. The shield located between the impeller and the stationary wing provides a barrier to the front edge of the wing from the tip of the impeller blade, thus reducing the passing noise of the blade.

6. Multiple stages In the illustrated embodiment, the blower comprises three stages with three corresponding impellers. In this embodiment, one impeller is located on one side of the motor and two impellers are located on the other side of the motor.

In an alternative embodiment, the blower may include two stages, one on each side of the motor. Yet another embodiment uses four stages, two on each side of the motor. Another embodiment is a single stage configuration. A further embodiment comprises a plurality of stages on only one side of the motor.

7. Alternative embodiment The following shows a blower according to an alternative embodiment of the present invention. In each embodiment, air enters the blower axially at one end and exits the blower axially at the other end.

7.1 Two-stage blower FIGS. 11 to 16 show a blower 400 according to another embodiment of the present invention. As shown, the blower 400 includes two stages with two corresponding impellers 450, 452. In this embodiment, the two impellers are placed on the same side of the magnet 462 and the stator assembly 465, but the bearing 444 is placed between the impellers 450, 452.

Such blowers can be used for snoring PAP, CPAP, APAP and / or VPAP and can be configured to provide a variant of the ventilator.

7.1.1 Small size The blower 400 has a relatively small size that results in a smaller or mini size blower. For example, as shown in FIG. 14, the blower 400 may have a total diameter d of about 50-60 mm, eg 53 mm, and a total length l of about 40-50 mm, eg 44 mm. However, other suitable sizes are possible.

7.1.2 Overview The fixed parts of the blower 400 are a chassis 470 with first and second housing components 472 and 474, a stator component 480 including a vane 485, and first and second shields 490, 492. And include. The rotating portion of the blower 400 includes first and second impellers 450, 452 configured to be driven by a motor 440. The motor includes a magnet 462 provided on the shaft 460 and the stator assembly 465 to cause a rotational movement of the shaft 460. In one embodiment, the motor may include two poles (due to its small size), no sensor, and / or no groove (due to low noise).

The blower 400 is generally cylindrical and has an inlet 430 provided by the first housing component 472 at one end and an outlet 420 provided by the second housing component 474 at the other end. As best shown in FIGS. 12 and 16, outlet 420 has a ring or ring shape. In one embodiment, the inlet may also have a ring or ring shape (not shown).

Similar to the above embodiments, the blower 400 has axial symmetry, with air entering the blower axially at one end and exiting the blower axially at the other end. Such a configuration can result in relatively low noise during use, for example due to axisymmetry and / or low vortex chamber turbulence.

7.1.3 Fixed part As best shown in FIGS. 15 and 16, the stator component 480 engages (eg, press-fits) into the corresponding opening 491 provided in the shield 490 to secure the shield 490 in place. Includes a cylindrical hub 486. Further, the hub 486 includes a recess 488 that holds or houses a bearing 444 that rotatably supports the shaft 460. As shown, the bearing 444 is housed in the stator component 480 so that it is located along the surface through which air is delivered from the impeller 450. This configuration saves axial space as the bearings 444 are located outside the enclosure surrounding the motor components (ie, stator assembly and magnets).

As best shown in FIGS. 15 and 16, housing component 474 includes a stationary wing 487 that directs flow towards outlet 420. Further, the housing component 474 includes an outer annular flange 478 and a hub 475 that provides an inner annular flange 476 that supports the motor components. Specifically, the inner annular flange 476 holds or houses a bearing 446 that rotatably supports the shaft 460. The outer annular flange 478 holds or houses the stator assembly 465. The shield 492 engages (eg, press-fits) the outer annular flange 478 with the magnet 462 on the shaft 460 so as to surround the stator assembly 465 within the housing component 474.

In one embodiment, the housing component 474 may be made of metal so that the housing component 474 can act as a heat sink that conducts and dissipates heat generated from the stator assembly 465 during use. Also, at least a portion of the outer annular flange 478 that supports the stator assembly 465 is exposed to the flow of air, which allows the stator assembly 465 to flow as air flows through the housing component 474 during use. Cooling is possible. However, the housing components may be made of other suitable materials, such as aluminum, plastic, etc., along with other blower components.

7.1.4 Rotating part In the illustrated embodiment, each impeller 450, 452 comprises a plurality of continuously curved or linear blades 454 sandwiched between a pair of disc-shaped enclosures 455, 456. The lower enclosure 456 incorporates a hub or bush configured to receive the shaft 460. Further, each of the impellers 450 and 452 includes a tapered configuration in which the blade 454 tapers toward the outer edge. Further details of the impeller are disclosed in Patent Document 5, which is incorporated herein by reference in its entirety. Such a configuration can result in a relatively fast pressure response, for example due to the impeller with relatively low inertia.

7.1.5 Fluid flow path In the first stage, air or gas enters the blower 400 at inlet 430 and passes into the first impeller 450, where the air is tangentially accelerated and directed radially outward. The air then has a large tangential velocity component and an axial component that passes through the gap 464 defined by the outer edge of the shield 490 and the inner surface of the housing component 472. Flow to. Air then enters the vane 485 formed within the stator component 480 and is directed radially inward towards hole 483 and then towards the second stage.

In the second stage, air or gas passes into the second impeller 452, where it is tangentially accelerated and directed radially outward. The air then has a large tangential velocity component and an axial component that passes through the gap 466 defined by the outer edge of the shield 492 and the inner surface of the housing component 474, spirally. Flow to. The air then enters the stationary wing 487 formed within the housing component 474 and is directed towards the outlet 420.

7.1.6 Support system As shown in FIG. 17, the blower 400 may be supported by a support system in an outer casing 415 (which forms part of an NIVV device, such as a PAP device). The outer casing 415 includes a base portion 416 and a cover 418 provided on the base portion 416. The support system includes a side support 424, a top support 425, a bottom support 426, or a combination thereof that supports the blower 400. The support system may also be configured to provide a seal between the inlet and outlet sides of the blower 400.

The side support 424 may be in the form of an annular flexible ring configured to support the blower in a flexible and / or vibrationally insulated manner within the outer casing 425. Further, the flexible ring 424 separates the inlet of the outer casing 425 from the outlet of the outer casing 425 so as to avoid the need for a connecting pipe that directs the flow towards the outlet of the outer casing. The flexible ring 424 may also provide a seal between the base portion 416 and the cover 418 of the outer casing 415.

The bottom support 426 includes a deflection member 427 (eg, a leaf spring) and a conduction member 428. In use, the bottom support 426 provides a flexible structure that insulates (eg, vibrates) the blower 400 from the outer casing 415. In one embodiment, the conductor 428 is coupled to the stator assembly 465 to conduct current from an external source to the stator assembly 465.

7.2 Two-stage blower with bearing tube FIG. 18 shows a two-stage blower 500 according to another embodiment of the present invention. The two-stage blower 500 is the same as the blower 400 described above. In contrast, the second housing component 574 and the second shield 592 provide different structures that support the motor components.

As shown, the second housing component 574 includes a stationary wing 587 that directs flow towards outlet 520. In addition, housing component 574 includes a hub 575 that results in a ring-shaped flange 576. The annular flange 576 is constructed to engage the underside of the stator assembly 565.

The second shield 592 includes a tube portion 595 extending from it (eg, integrally formed as one component). As shown in the figure, the stator assembly 565 is such that the stator assembly 565 is surrounded and sandwiched between the annular flange 576 of the second housing component 574 and the tapered protrusion 593 of the shield 592. Is provided along the outer surface of the pipe portion 595.

In the illustrated embodiment, the outer surface of the stator assembly 565 is exposed to the flow of gas through the housing component 574, which allows the stator assembly 565 to cool during use. Also, the heat from the stator assembly can be used to heat the gas for the patient without the need for a separate heater.

The inner surface of the tube portion 595 holds or houses a bearing 546 that rotatably supports the shaft 560. Further, the tube portion 595 surrounds the magnet 562 on the shaft 560, and the magnet 562 is aligned with the stator assembly 565. In one embodiment, the tube portion 595 has a significant loss of magnetic flux density and / or, in some cases, increased heat so that the stator assembly 565 can act on a magnet 562 located within the tube portion 595. It may be "magnetically permeable" without. Further details of the magnetically permeable tube are disclosed in Patent Document 7, which is incorporated herein by reference in its entirety.

A counterbore ring 598 may optionally be provided at the end portion of the shaft 560 (eg, opposite the end portion supporting the impeller).

In the illustrated embodiment, the hub 575 projects further outward from the housing than the hub 475 of the blower 400 described above. This configuration may add about 1-10 mm (eg 5 mm) to the height of the blower 500 with respect to the blower 400, for example. For example, the blower 500 may have a total diameter d of about 50-60 mm (eg 53 mm) and a total length l of about 40-55 mm (eg 49 mm). However, other suitable sizes are possible.

7.3 Three-stage blower with tapered configuration FIG. 19 shows a three-stage blower 600 according to another embodiment of the present invention. Similar to the three-stage blower 100 described above, the blower 600 comprises one impeller 650 located on one side of the motor 640 and two impellers 652, 654 located on the other side of the motor 640. Includes 3 steps.

In the illustrated embodiment, the impellers 650, 652, 654 of the blower 600, respectively, have a tapered configuration. In addition, the corresponding parts of the housing 670 and stator components 680, 682 are tapered to match the tapered configuration of the impellers 650, 652, 654.

In the illustrated embodiment, each impeller 650, 652, 654 comprises a plurality of continuously curved or linear blades 653 sandwiched between a pair of disc-shaped enclosures 655, 656. The lower enclosure 656 incorporates a hub or bush configured to receive the shaft 660. In addition, each of the impellers 650, 652, and 654 includes a tapered configuration in which the blade 653 tapers toward the outer edge. Further details of the impeller are disclosed in Patent Document 5, which is incorporated herein by reference in its entirety.

The upper wall 673 of the housing component 672 is tapered to match the tapered configuration of the impeller 650, and the corresponding stator components 680, 682 lower walls 657, 659 are the impeller 652, It can be tapered to match the tapered configuration of 654.

Further, in the illustrated embodiment, the central portion 693 of the lower shielding portion 692 is shaped so as to direct the air flow downward toward the outlet 620. The central portion 693 includes voids 696 along the surface facing the impeller 654, for example, to maintain a constant cross section / thickness in the shield 692 and to save material costs.

As shown, bearings 644 and 646 that support the shaft 660 are provided in the housing 642 of the motor 640. In an alternative embodiment, another bearing (ie, a third bearing) may be added towards the end of the shaft 660 near the lower impeller 654 to add additional support. In another alternative embodiment, rather than adding a third bearing, one of the bearings 644 or 646 in the motor housing 642 is held in that position and the other bearing 644 or 646 adds additional support. May be moved towards the end of the shaft 660 near the lower impeller 654. However, other bearing configurations are possible.

In this embodiment, the blower 600 may be supported by a support system in an outer casing 615 (which forms part of an NIVV device, such as a PAP device). The support system includes a side support 624 that supports the sides of the blower 600 and a bottom support 626 that supports the bottom of the blower 600.

The side and bottom supports 624, 626 may be flexible members (eg, elastomers) that insulate (eg, vibrate) the blower 600 from the outer casing 615. As shown, the side support 624 is configured to engage the corresponding nail 635 provided on the blower 600. The bottom support 626 provides a conduit from outlet 620 of the blower 600 to outlet 617 of the outer casing 615 (eg, which can be connected to an air delivery conduit that sends pressurized air to the patient for treatment). ..

8. Other comments Although the present invention has been generally described for centrifugal pumps, the present invention is not limited to this form, and may take the form of a mixed flow type.

An aspect of the present invention is that the chamber defining the air flow path is approximately axially symmetrical. This does not mean that the entire air flow path of the device using the blower according to the present invention must also be axially symmetrical. Modifications within the scope of the present invention may include some asymmetrical portions. These asymmetrical parts may be in low speed regions where loss and noise are less affected.

In one embodiment, the blower allows for an air flow supply pattern that maintains symmetry, regardless of flow velocity, via the impeller and into the vortex chamber. As a result, the level of noise emission of the passing sound of the blades is lowered, and the level of noise emission of turbulent flow is lowered.

Although the present invention has been described with respect to what is currently considered to be the most practical and preferred embodiment, the invention is not limited to the disclosed embodiments and, conversely, the spirit and scope of the invention. It should be understood that it is intended to extend to the various modifications and equal components contained within. Also, the various embodiments described above may be implemented in conjunction with other embodiments, for example, an embodiment of one embodiment may be combined with an embodiment of another embodiment to realize yet another embodiment. Good. In addition, each independent feature or component of any given assembly may constitute additional embodiments. Further, the present invention has specific uses for patients suffering from OSA, but patients suffering from other diseases (eg, congestive heart failure, diabetes, morbid obesity, stroke, obesity surgery, etc.) may from the above teachings. It will be understood that it can be profitable. Moreover, the above teachings also have patient and non-patient applicability in non-medical applications.

10 Centrifugal blower 20 exit 30 entrance 40 electric motor 50 impeller 60 shaft 100 blower 120 exit 130 entrance 140 electric motor 150 impeller 152 Impeller 154 Impeller 160 shaft 164 Gap 166 Gap 170 external housing 172 External housing parts 174 External housing parts 180 Stator component 181 holes 182 Stator component 183 holes 184 Stator component 185 Static wings 187 Static wings 190 Shield (disk) 192 Shield 200 feathers 202 enclosure 204 enclosure 206 hub 208 Central opening 250 impeller 260 motor shaft 280 Stator 285 Static wings 290 Shield 350 impeller 352 Enclosure 354 enclosure 355 feathers 360 motor shaft 380 Stator 385 Static wings 400 blower 415 External casing 416 base 418 cover 420 exit 424 Side support 425 Top support 426 Bottom support 427 Deflection member 428 Conductive member 430 entrance 440 motor 444 bearing 446 bearing 450 impeller 452 Impeller 454 feathers 455 Enclosure 456 Enclosure 460 shaft 462 magnet 464 Gap 465 Stator assembly 466 gap 470 housing 472 Housing parts 474 housing parts 475 hub 476 Inner annular flange 478 Outer annular flange 480 Stator component 483 holes 485 static wings 486 hub 487 Static wings 488 recess 490 Shield 491 opening 492 Shield 500 blower 520 exit 546 bearing 560 shaft 562 magnet 565 Stator assembly 574 Second housing part 575 hub 576 flange 587 Static wings 592 Second shield 593 Overhang 595 pipe part 598 Balance ring 600 blower 615 External casing 617 exit 620 exit 624 Side support 626 Bottom support 635 nail 640 motor 642 housing 644 Bearing 646 bearing 650 impeller 652 Impeller 653 feathers 654 Impeller 655 enclosure 656 Enclosure 657 wall 659 wall 660 shaft 670 chassis 672 housing parts 673 wall 680 Stator component 682 Stator component 692 Shield 693 Central part 696 void