AU2014271265B2

AU2014271265B2 - Respiratory assistance apparatus with motorised turbine and deflectors

Info

Publication number: AU2014271265B2
Application number: AU2014271265A
Authority: AU
Inventors: Hadrien Guiducci
Original assignee: Air Liquide Medical Systems SA
Current assignee: Air Liquide Medical Systems SA
Priority date: 2013-12-10
Filing date: 2014-12-03
Publication date: 2018-08-30
Anticipated expiration: 2034-12-03
Also published as: EP2884116B1; FR3014320B1; FR3014320A1; AU2014271265A1; CN104696243A; CA2869191A1; EP2884116A1

Abstract

Abstract The invention relates to a respiratory assistance apparatus comprising an internal compartment having an upper wall, a motorized turbine comprising an electric motor driving a drive shaft 5 carrying at least one vaned wheel, a volute lying on top of the said motorized turbine and enclosing at least a part of the said at least one vaned wheel, the said volute comprising a gas entry opening and a gas exit opening, and a hood lying on top of the said volute, the said hood comprising a gas passage located facing the entry opening of the volute so as to allow fluidic communication between the said gas passage of the hood and the said entry opening of the 10 volute, and the said hood being separated from the upper wall of the internal compartment so as to create a gas circulation spacing between them. According to the invention, a plurality of deflectors having a longitudinally rectilinear or incurvate wall are arranged in the spacing between the hood and the upper wall of the internal compartment.

Description

The invention relates to a respiratory assistance apparatus comprising an internal compartment having an upper wall, a motorized turbine comprising an electric motor driving a drive shaft 5 carrying at least one vaned wheel, a volute lying on top of the said motorized turbine and enclosing at least a part of the said at least one vaned wheel, the said volute comprising a gas entry opening and a gas exit opening, and a hood lying on top of the said volute, the said hood comprising a gas passage located facing the entry opening of the volute so as to allow fluidic communication between the said gas passage of the hood and the said entry opening of the 10 volute, and the said hood being separated from the upper wall of the internal compartment so as to create a gas circulation spacing between them. According to the invention, a plurality of deflectors having a longitudinally rectilinear or incurvate wall are arranged in the spacing between the hood and the upper wall of the internal compartment.

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2014271265 03 Dec 2014

Respiratory Assistance Apparatus with Motorized Turbine and Deflectors

This application claims priority from French patent application FR 1362355 filed

December 2013, the contents of which are to be taken as incorporated herein by this 5 reference.

The invention relates to a respiratory assistance apparatus equipped with a motorized turbine for generating a gas flow, in particular an air flow, comprising deflectors arranged between the upper wall of the internal casing containing the turbine and the hood lying on top of the said turbine.

The discussion of documents, acts, materials, devices, articles and the like is included in this specification solely for the purpose of providing a context for the present invention. It is not suggested or represented that any or all of these matters formed part of the prior art base or were common general knowledge in the field relevant to the present invention as it existed before the priority date of each claim of this application.

Where the terms comprise, comprises, comprised or comprising are used in this specification (including the claims) they are to be interpreted as specifying the presence of the stated features, integers, steps or components, but not precluding the presence of one or more other features, integers, steps or components, or group thereof.

Some respiratory assistance apparatuses employ a motorized turbine also referred to 20 as a “blower” or “micro-blower”, making it possible to take in ambient air and deliver it at a nonzero flow rate to a patient connected to the respiratory apparatus equipped with the said turbine. Sometimes, the air is enriched with oxygen before it is administered to the patient by inhalation. Such a respiratory assistance apparatus is described, in particular, by the documents EP-A-2102504 and EP-A-2122180.

The motorized turbine conventionally comprises an electric motor driving one or more vaned wheels in rotation via its axle or rotary drive shaft. The vaned wheel(s) are arranged in a compartment referred to as a “volute”, the upper wall of which forms a cover covering and protecting the vaned wheel.

The volute has a gas entry opening through which the air taken in enters the volute, 30 and an exit opening which is furthermore in fluidic communication with an exit duct through which the air taken in by the vaned wheel during its rotation is expelled.

On top of the volute itself, there is conventionally a hood comprising an air passage located facing the gas entry opening of the volute, so as to create fluidic continuity between these parts.

The motor/wheel/volute assembly is generally fixed inside the respiratory apparatus by a flexible system, such as a foam sleeve or the like enclosing these parts, making it possible to reduce the vibrations transmitted and the noise generated by the turbine.

However, precise positioning of this motor/wheel/volute assembly has a direct influence on the performance of the turbine.

Thus, if the space lying above the volute and the hood, through which the air passes before entering the compartment containing the wheel, is reduced too much, as a result of an impact or an excessive reduced pressure (suction), the passage cross section of the air then becomes reduced too greatly, which causes degradation of the performance of the turbine and of the gas flow rate generated.

The insertion of conical or cylindrical studs, or foam, in the air path through the space lying above the volute, in order to maintain a minimum spacing, is not an ideal solution because these elements can interfere with the air circulation and reduce the performance of the machine.

An aspect to be achieved is to improve the precise positioning of the turbine, in particular of the motor/wheel/volute/hood assembly, inside the compartment of a respiratory assistance apparatus, intended to accommodate this assembly, and to maintain a large gas passage cross section between the wall of the said compartment and the said motor/wheel/volute/hood assembly, even in the event of violent impact.

In one aspect, the present invention provides a respiratory assistance apparatus comprising:

- an internal compartment having an upper wall,

- a motorized turbine comprising an electric motor driving a drive shaft carrying at least one vaned wheel,

- a volute lying on top of the said motorized turbine and enclosing at least a part of the said at least one vaned wheel, the said volute comprising a gas entry opening and a gas exit opening, typically for air, the volute being formed by a lower volute part and an upper volute part, which are assembled together so as to define between them a housing containing the vaned wheel, and

- a hood lying on top of the said volute, the said hood comprising a gas passage located facing the entry opening of the volute so as to allow fluidic communication between the said gas passage of the hood and the said entry opening of the volute, and the said hood being separated from the upper wall of the internal compartment so as to create a gas circulation spacing between them, wherein a plurality of deflectors having a longitudinally rectilinear or incurvate wall shape are arranged in the spacing between the hood and the upper wall of the internal compartment.

Depending on the case, the respiratory assistance apparatus of the invention may comprise one or more of the following technical characteristics:

- the deflectors have a longitudinally incurvate wall shape.

- the deflectors are carried by the external surface of the hood or by the internal surface of the upper wall of the internal compartment, and they are preferably carried by the internal surface of the upper wall of the internal compartment.

- the internal compartment constitutes an internal casing comprising an upper wall and a side wall. It may be integrated directly with the structure of the casing.

- the deflectors are rigid, and the deflectors are preferably made of plastic material, for example a plastic of the acrylonitrile butadiene styrene (ABS) type, of the polycarbonate (PC) type or a mixture of the ABS-PC type.

- it comprises from 2 to 20 deflectors, preferably from 3 to 10 deflectors.

- the deflectors are walls arranged radially or approximately radially on the internal surface of the upper wall of the internal compartment.

- the upper wall of the internal compartment has a dome shape.

- depending on the particular embodiment, the upper wall of the internal compartment comprises a central protuberance extending coaxially in the direction of the drive shaft of the turbine.

- the deflectors and the upper wall of the internal compartment are formed in a single piece, preferably by moulding.

- according to another embodiment, the deflectors are overmoulded on the upper wall of the internal compartment. In this case, the deflectors are made of flexible material, for example a thermoplastic elastomer (TPE) 60 Shore A.

- the deflectors are carried by the internal surface of the upper wall of the internal compartment, and bear on the external surface of the hood.

- the deflectors are carried by the internal surface of the upper wall of the internal compartment, and have a three-dimensional profile complementary to the external surface of the hood, that is to say the profile of the deflectors matches the external profile of the hood.

- the deflectors have a curved three-dimensional profile.

- the hood is formed from a flexible material, that is to say an elastic or deformable material, preferably silicone or a thermoplastic elastomer (TPE) of from 20 to 90 Shore A.

- the deflectors are configured and oriented in such a way as to impart a rotational movement to the gas before the said gas enters the volute.

- according to another embodiment, the deflectors are longitudinally rectilinear, that is to say straight, so as to straighten the gas and avoid or attenuate perturbations of the gas entering the turbine.

- the deflectors have a minimum height H of at least 1 mm, preferably at least 2 mm.

- the deflectors have a length L of at least 5 mm, preferably at least 10 mm.

- the volute is formed by a lower volute part referred to as the lower volute, and an upper volute part, referred to as the upper volute, which are assembled together so as to define between them a housing containing the vaned wheel.

- an acoustic core is arranged between the volute and the hood.

- the acoustic core is formed from a flexible or rigid material, preferably a flexible material, such as TPE 60 Shore A.

The invention will now be described in more detail with reference to the appended figures, in which:

- Figure 1 represents a view in section of an embodiment of a turbine assembly which can be arranged in the internal compartment of a respiratory assistance apparatus according to the present invention,

- Figure 2 is a bottom view of the dome forming the upper wall, carrying the deflectors, of the internal compartment of the respiratory assistance apparatus of Figure 1,

- Figures 3A and 3B schematize the air flows under the dome of Figure 2 according to two different embodiments of the deflectors,

- Figure 4 schematizes the air flows in the turbine assembly of Figure 1,

- Figure 5 represents an exploded view of the turbine assembly of Figure 1,

- Figure 6 shows the turbine assembly of Figure 1 inserted into the internal compartment of a respiratory assistance apparatus according to the present invention,

- Figure 7 shows the turbine assembly of Figure 1 extracted from the compartment forming a casing around the said turbine assembly, and

- Figure 8 schematizes a deflector in an outline view.

Figure 1 represents an embodiment, seen in section, of a turbine assembly 1,2, 10 incorporated into the internal compartment 9 of a respiratory assistance apparatus. This turbine assembly is also shown extracted from the compartment 9 in Figure 7, in exploded view in Figure 5, and inserted into a respiratory assistance apparatus 30 in Figure 6.

As can be seen, the internal compartment 9 forms an internal casing of the apparatus 30, inside which the turbine assembly, comprising the motorized turbine 1 and its various elements, as detailed below, is positioned and held. The internal compartment 9 may constitute a casing contained permanently inside the apparatus 30 itself, or it may be removable, that is to say capable of being extracted from the apparatus 30.

More precisely, the internal compartment 9 comprises a peripheral wall 9b, of cylindrical overall shape, enclosing the turbine assembly. Lying on top of the peripheral wall 9b, there is an upper wall 9a, here in the shape of a dome, which comprises on its internal surface a central protuberance 9c extending in the direction of the turbine assembly and, more particularly, coaxially with the shaft 10 of the motor 1.

Lor its part, the turbine assembly comprises a motorized turbine 1, 10 comprising an electric motor 1 driving a drive shaft 10, that is to say a rotary axle, on which a vaned wheel 2 is arranged. According to another embodiment, the drive shaft 10 may carry a plurality of vaned wheels 2 arranged in parallel on the axle 10. The motor 1 of the turbine is supplied, in the conventional way, with electric current by electrical wires 18 or the like carrying an electric current coming from a current source, such as one or more batteries, or the mains.

Lying on top of the motorized turbine 1, 10, there is a volute 4, 5 which forms a wheel housing or compartment 17 enclosing the vaned wheel 2. The volute 4, 5 is formed here by two parts, which are assembled together, namely a lower volute part 4, also referred to as the lower volute, and an upper volute part 5, also referred to as the upper volute, which define the wheel compartment 17 and “sandwich” the vaned wheel 2. These two volute parts 4, 5 are fixed to one another in a leaktight manner, for example by adhesive bonding or the like, or with the aid of an additional/intermediate piece, in order to avoid air leaks at their junction.

The lower volute 4 is arranged below the vaned wheel 2, that is to say between the wheel 2 and the motor 1 of the turbine, whereas the upper volute is arranged above the vaned wheel 2, that is to say on the other side of the vaned wheel 2 from the lower volute 4; this arrangement is illustrated in Ligure 1.

A separating plate 3 is furthermore provided, forming the bottom of the wheel compartment 17 and separating the wheel 2 from the motor 1, as can be seen in Ligure 1. The separating plate 3 is in this case integrated with the motor.

Furthermore, as illustrated in Figure 1, an empty space is furthermore provided below the wheel 2, between the bottom plate 3 and the said vaned wheel 2, as well as an annular seal 3’ located below the bottom plate 3 on top of the motor 1, making it possible to ensure gastightness between the motor 1 and the lower volute 4, that is to say the annular seal 3’ is sandwiched between the motor 1 and the lower volute 4.

The volute 4, 5 furthermore comprises a gas entry opening 11 through which the gas enters, typically air or air enriched with oxygen (the air being enriched upstream), which is taken in by the vaned wheel 2 during its rotation, and a gas exit opening 12 through which the gas, typically air or air enriched with oxygen, taken in by the wheel 2 is expelled.

Before entering the volute 4, 5, that is to say the housing 17 containing the rotary vaned wheel 2, the gas passes through a hood 7 which lies on top of the volute 4, 5. This hood 7 has a central passage 19, which is located facing the entry opening 11 of the volute and which is in fluidic communication with the said entry opening 11 so as to guide the air taken in towards the interior of the volute 4, 5, that is to say towards the wheel compartment 17.

As can be seen in Figure 1, the central protuberance 9c extends at least partially in the central passage 19 in the direction of the axle 10 of the motor 1. Preferably, the central protuberance 9c and the axle 10 of the motor 1 are coaxial, or approximately coaxial.

Furthermore, the internal compartment 9 comprises an exit duct 16 for gas flows, which is in fluidic communication with the gas exit opening 12 of the volute 4, 5.

Arranged between the hood 7 and the upper volute 5, there is an acoustic core 6, which may be rigid or flexible, preferably flexible, and which makes it possible to attenuate the noise generated by the rotation of the wheel 2. For example, the acoustic core 6 may be formed from silicone or thermoplastic elastomer (TPE) of between 30 and 90 Shores.

The hood 7 is separated from the upper wall 9a of the internal compartment 9 forming the casing, so as to create a space or spacing 15 between them for circulation of the gas, as detailed below.

Furthermore, the motor 1 of the turbine, and preferably at least a part of the lower volute 4, are enclosed in a sleeve 20 made of silicone, TPE of between 30 and 90 Shores, or the like, making it possible to reduce the sound emission, that is to say the noise generated by the rotations of the motor 1 and the vaned wheel 2.

In the embodiment of Figure 1, a gas passage has also been arranged along the motor 1, so that the gas, i.e. the air, flows over the external body of the said motor 1 before continuing on its way through the spacing 15, then passing through the hood 7 before then arriving in the volute 4, 5, as schematized in Figure 4.

This makes it possible to cool the motor 1 by removing some of the heat generated during its rotation. This configuration is not compulsory, however, since the gas could arrive radially, directly in the spacing 15, that is to say without passing around the motor 1.

According to the present invention, in order to ensure a sufficient spacing 15 between the hood 7 and the upper wall 9a of the internal compartment 9, typically a spacing of at least 2 or 3 mm, a plurality of deflectors 14 are provided, formed by small rectilinear walls (Fig. 3B) or incurvate walls (Fig. 3A), preferably incurvate walls, which are arranged in the spacing 15 between the hood 7 and the upper wall 9a of the internal compartment 9. Such shapes make it possible to improve the flow and the performance of the turbine.

As shown in the figures, in the embodiment presented here, the deflectors 14 are arranged on the internal surface of the upper wall or dome 9a of the compartment 9. Nevertheless, all or some of the deflectors 14 could also be arranged directly on the external surface of the hood 7.

The incurvation of the deflectors 14 may be identical for all the deflectors 14, or some may have a different incurvation from the others. The radius of curvature of the incurvate deflectors 14, that is to say the desired incurvation, is selected so as to give them an aerodynamic shape generating the least possible pressure losses while imparting a given pre-rotation to the gas flow, as schematized in Figure 3A, before it enters the hood 7. Specifically, pre-rotation of the gas flow may be advantageous because it can make it possible to improve the characteristics of flow rate and/or pressure of the gas delivered by the respiratory apparatus 30.

More generally, the incurvate deflectors 14 (Fig. 3A) or rectilinear deflectors 14 (Fig. 3B) are oriented towards the centre of the dome 9a, that is to say radially in the direction of the protuberance part 9c which extends towards the drive shaft 10 while being coaxial therewith, which makes it possible to orientate the gas flow in the spacing 15 towards the centre of the dome forming the upper wall 9a of the compartment 9, either in a linear/translational (see the arrows in Fig. 3B), or rotary (see the arrows in Fig. 3A) manner.

The deflectors 14 are advantageously formed in a single piece with the upper wall 9a of the internal compartment or casing 9 of the respiratory apparatus, for example in one piece moulded from plastic material, such as ABS, ABS-PC or PC. It is also conceivable for the deflectors 14 to be made of flexible materials with a high Shore hardness in order to increase the vibrational decoupling while maintaining sufficient rigidity, this being done so that the assembly is not crushed.

In order to ensure good holding of the turbine assembly in position inside the compartment 9, at least 2 deflectors 14 are provided, preferably at least 3 deflectors 14. In all cases, the deflectors 14 constitute rigid aerodynamic fins ensuring that the spacing 15, that is to say the passage area of the gas above the hood 7, is always at least equal to a given value, typically at least 2 to 5 mm, which corresponds to a passage cross section of approximately 1 to 30 cm².

In order to do this, as illustrated in Figure 8, the deflectors 14, whether they are rectilinear or incurvate, typically have a minimum height H of at least 2 mm and a minimum length L of at least 5 mm, preferably at least 10 mm, or even up to about 30 mm, as illustrated in Figure 8.

When the turbine assembly comprising the hood 7 is inserted into the compartment 9 of a respiratory apparatus 30, as illustrated in Figure 6, the deflectors 14 carried by the internal surface of the upper wall 9a of the internal compartment 9 bear on the external surface of the hood 7, as can be seen in Figure 1.

In order to improve the contact between the deflectors 14 and the hood 7, the deflectors 14 are shaped so as to have a three-dimensional profile complementary to the external surface of the hood 7. In other words, the contact surface 14a of the deflectors 14, which comes in mechanical contact with the external surface of the hood 7, has a profile, in particular a curvature, complementary to that of the hood 7, so as to match the external contours of the said hood 7 at the positions where the deflectors bear on the hood 7.

Advantageously, the hood 7 is made of a flexible material, that is to say a deformable and/or elastic material, such as TPE or silicone. This makes it possible, in the event of axial impact, to avoid crushing of the rigid deflectors 14 against the hood 7, since any impact will be dampened by the flexible hood 7, which then acts as an absorber for shocks oriented along the axle of the motor 1, but also radial shocks.

Specifically, the use of the three-dimensional deflectors according to the invention means that a more or less sizeable part of the radial forces can be taken up.

A respiratory assistance apparatus 30 according to the present invention may be used to treat various respiratory diseases, in particular chronic obstructive bronchopneumopathy (COBP), acute respiratory distress syndrome (ARDS), obesity hypoventilation syndrome (OHS), obstructive sleep apnoea syndrome (OSAS), neuromuscular diseases, cystic fibrosis, thoracic deformations, Cheyne-Stokes respiration, tuberculosis, pulmonary oedema, etc.

2014271265 03 Dec 2014 ίο

2014271265 03 Dec 2014

Claims

The claims defining the invention are as follows:

1. Respiratory assistance apparatus comprising:

- an internal compartment having an upper wall,

2. Apparatus according to claim 1, wherein the deflectors are carried by the external surface of the hood or by the internal surface of the upper wall of the internal compartment.

3. Apparatus according to claim 2, wherein the deflectors are carried by the internal 25 surface of the upper wall of the internal compartment.

4. Apparatus according to any one of the preceding claims, wherein the deflectors are rigid.

30 5. Apparatus according to claim 4, wherein the deflectors are made of plastic material.

5 the internal compartment.

5 - a motorized turbine comprising an electric motor driving a drive shaft carrying at least one vaned wheel,

- a volute lying on top of the said motorized turbine and enclosing at least a part of the said at least one vaned wheel, the said volute comprising a gas entry opening and a gas exit opening, the volute being formed by a lower volute part and an upper volute part, which

10 are assembled together so as to define between them a housing containing the vaned wheel, and

- a hood lying on top of the said volute, the said hood comprising a gas passage located facing the entry opening of the volute so as to allow fluidic communication between the said gas passage of the hood and the said entry opening of the volute, and the said hood

15 being separated from the upper wall of the internal compartment so as to create a gas circulation spacing between them, wherein a plurality of deflectors having a longitudinally rectilinear or incurvate wall are arranged in the spacing between the hood and the upper wall of the internal compartment.

6. Apparatus according to any one of the preceding claims, wherein it comprises from 2 to

20 deflectors.

2014271265 03 Dec 2014

7. Apparatus according to claim 6, wherein it comprises from 3 to 10 deflectors.

8. Apparatus according to any one of the preceding claims, wherein the deflectors are walls arranged radially or approximately radially on the internal surface of the upper wall of

9. Apparatus according to any one of the preceding claims, wherein the upper wall of the internal compartment has a dome shape.

10 10. Apparatus according to any one of the preceding claims, wherein the deflectors and the upper wall of the internal compartment are formed in a single piece.

11. Apparatus according to claim 10, wherein the deflectors and the upper wall of the internal compartment are formed by moulding.

12. Apparatus according to any one of the preceding claims, wherein the deflectors are carried by the internal surface of the upper wall of the internal compartment, and bear on the external surface of the hood.

20

13. Apparatus according to any one of the preceding claims, wherein the deflectors are carried by the internal surface of the upper wall of the internal compartment, and have a threedimensional profile complementary to the external surface of the hood.

14. Apparatus according to any one of the preceding claims, wherein the deflectors have a 25 curved three-dimensional profile.

15. Apparatus according to any one of the preceding claims, wherein the hood is formed from a flexible material.

30

16. Apparatus according to claim 15, wherein the the hood is formed from silicone or TPE.

17. Apparatus according to any one of the preceding claims, wherein the deflectors are configured and oriented in such a way as to impart a rotational movement to the gas before the said gas enters the volute.

2014271265 03 Dec 2014

18. Apparatus according to any one of the preceding claims, wherein the deflectors have a minimum height of at least 2 mm.

5

19. Apparatus according to claim 18, wherein the minimum height is at least 4 mm.

20. Apparatus according to any one of the preceding claims, wherein the deflectors have a length of at least 5 mm.

10 21. Apparatus according to claim 20, wherein the length is at least 10 mm.

2014271265 03 Dec 2014