FR3110437A1 - Breathing assistance device - Google Patents

Abstract

Title: Breathing assistance device. The main object of the present invention is a device for assisting the breathing (1) of a patient, comprising at least one inspiration circuit (16), an expiration circuit (20), as well as a device for breathing in. circulation (28) of the air in the inspiration circuit (16), characterized in that it comprises two acoustic attenuation members (45, 46) arranged one upstream and the other downstream of the circulation device with respect to the direction of air flow in the inspiration circuit, each sound attenuation member extending mainly along an axis of elongation (A1, A2) so that these axes of elongation are perpendicular to each other. Figure for the abstract: Figure 1.

Description

Breathing assistance device

The present invention falls within the field of patient breathing assistance devices, and in particular breathing assistance devices for intubated patients.

Patients in respiratory distress require respiratory assistance to ensure oxygenation of their tissues. The breathing assistance devices currently used conventionally comprise at least one conduit dedicated to patient inspiration on which is installed at least one air circulation device. This device for circulating air is adapted to generate a flow of air which is treated, for example by adding oxygen, before being directed towards the respiratory system of the patient, and thus ensuring the respiration of the latter . Such respiratory assistance devices also include an exhalation line through which the air exhaled by the patient circulates and is then expelled.

To facilitate, or to force if necessary, the inspiration and the expiration of the patient, valves allowing or blocking the circulation of the air through the line dedicated to the inspiration or the expiration of the patient are installed. Thus, a valve blocks the circulation of air in the pipe dedicated to exhalation when air enriched in dioxygen circulates towards the patient to spread more particularly in the respiratory system of the patient. Once a sufficient quantity of enriched air is brought to the patient, a valve blocks the air circulation in the line dedicated to the inspiration of the patient and the valve blocking the circulation in the line dedicated to the expiration is positioned to allow the expiration of the air contained by the patient's respiratory system through the pipe dedicated to expiration.

The device for circulating air comprises in particular a motorized fan, configured to suck air from outside the casing and direct it at high pressure towards the patient, the motorized fan being arranged on the pipe dedicated to the inspiration.

The implementation of such a fan generates operating noises and in particular mouth noises, that is to say the noises produced by the circulation of air as it passes between the inlet and the outlet of the motorized fan. . Depending on the needs for attenuation of the corresponding sound power level, an acoustic attenuation device, or silencer, can be associated with the circulation device, upstream or downstream of the motorized fan.

This circulation device and the associated silencer(s) must in particular be integrated into a box with the rest of the components of the breathing assistance device, namely the valves and in particular the batteries allowing independent power supply to each of the motors.

The present invention falls within this context and aims to propose a breathing assistance device which takes into account the problems of size of the various parts composing it.

More particularly, the main subject of the present invention is a device for assisting the breathing of a patient, comprising at least one inspiration circuit, one expiration circuit, as well as a device for circulating the air in the inspiration circuit, characterized in that it comprises two acoustic attenuation members arranged one upstream and the other downstream of the circulation device with respect to the direction of air flow in the inspiration circuit, each acoustic attenuation member extending mainly along an axis of elongation so that these axes of elongation are perpendicular to one another.

In an assistive breathing device, an air circulating device, which may also be referred to as a powered ventilating device, is required to take in air from outside the device, compress it, and direct it. in the direction of the patient whom one wishes to help or force to breathe. The circulating device comprises in particular a ventilation member, which can take the form of a centrifugal compression wheel, the operation of which generates unwanted noise in a medical application. Acoustic attenuation devices are arranged on either side of the ventilation device in order to reduce this noise as much as possible, and in particular mouth noises as mentioned.

A perpendicular arrangement of these acoustic attenuation members, also known as mufflers, makes it possible to optimize the positioning in the breathing assistance device of the assembly formed by these three components which are the mufflers and the ventilation member, the assembly being able in particular to be arranged from a corner of a structural casing of the breathing assistance device.

According to a series of optional characteristics of the invention, taken alone or in combination, it can be provided that:

- the breathing assistance device comprises a housing within which a first acoustic attenuation member arranged upstream of the circulation device is arranged horizontally and within which a second acoustic attenuation member arranged downstream of the device circulation is arranged vertically;

- the first acoustic attenuation member arranged upstream of the circulation device is arranged longitudinally, along a longitudinal wall of the housing;

- the first acoustic attenuation member arranged upstream of the circulating device extends along an upper horizontal wall of the housing, the second acoustic attenuating member extending between the circulating device and a lower horizontal wall of the case.

According to an optional characteristic of the invention, the breathing assistance device comprises a casing on which the circulation device is fixed, the acoustic attenuation members being respectively fixed on a fixing plate of the casing so that the acoustic attenuation members, the circulating device and the casing form a unitary module.

The assembly previously mentioned by the three components that are the silencers and the ventilation unit is in this context easily manipulated by an operator, in a single operation, and the assembly can be fixed more easily and more quickly in the housing of the breathing assistance device. In particular, this set can be easily brought inside the case while the other components are already present in the case.

According to a series of optional characteristics of the invention, taken alone or in combination, it can be provided that:

- the single module is fixed to a wall of the box by means of a fixing plate of the casing;

- the casing is fixed to the casing by means of a casing fixing plate separate from the casing fixing plates on which the acoustic attenuation devices are fixed;

- A damping material is injected into the volume defined by the housing of the unitary module.

According to a series of optional characteristics of the invention, taken alone or in combination, and here relating to the shape of the acoustic attenuation members, it is possible to provide that:

- at least one acoustic attenuation device comprises a cylindrical envelope inside which extends a perforated internal tube fluidly connected to the inspiration circuit or to the expiration circuit;

- the internal tube is connected to an inlet or outlet of a volute of the circulation device via a flexible connection;

According to an optional feature of the invention, the acoustic attenuation members have different dimensions, one dimension of the acoustic attenuation member arranged upstream of the circulation device being up to twice greater than a corresponding dimension of the acoustic attenuation member arranged downstream of the circulation device.

Such a difference in the sizing of the acoustic attenuation devices makes it possible to adapt the noise absorption needs according to the place where the silencers are positioned. Thus, the mouth noises downstream of the circulation device are attenuated by the connection of the air conduit to the patient, while the air conduit intended to bring air to the circulation device leads to the outside and may generate more noise in the medical environment in which the breathing assistance device is used.

According to an optional characteristic of the invention, the acoustic attenuation member arranged upstream of the circulation device has a cylindrical envelope whose average diameter is of the order of 120 mm and whose main dimension, along its axis of elongation, is of the order of 200mm.

According to an optional characteristic of the invention, the acoustic attenuation member arranged downstream of the circulation device has a cylindrical envelope whose mean diameter is of the order of 95 mm and whose main dimension, along its elongation axis, is of the order of 100mm.

According to an optional characteristic of the invention, the acoustic attenuation member comprises on the one hand three parts respectively produced by means of additive manufacturing and assembled to form a cylindrical assembly and on the other hand an internal tube produced distinctly and rendered secured to the cylindrical assembly.

According to an optional characteristic of the invention, the inspiration circuit comprises a member for mixing the air coming from the circulation device with a gas coming from a gas inlet pipe, and an accumulation device is arranged aeraulically between the acoustic attenuation member arranged downstream of the circulation device and the mixing member.

Other characteristics, details and advantages of the invention will emerge more clearly on reading the description which follows on the one hand, and several examples of embodiment given by way of indication and not limitation with reference to the appended schematic drawings on the other. part, on which:

is a schematic representation in perspective of a breathing assistance device according to the invention;

is a partial schematic representation of a breathing assistance device according to the invention, in which only have been made visible, within a housing of the device, a unitary module comprising a device for circulating the air and two acoustic attenuation members, as well as a casing forming a support for these components and allowing them to be fixed in the housing;

is a perspective representation of the unitary module as shown in the ;

is a representation, from another angle of perspective, of a variant of the unitary module illustrated in the ;

is a sectional view of the unitary module of the , making visible in particular an embodiment of the acoustic attenuation members, arranged upstream and downstream of the device for circulating the accumulation air;

is a cross-sectional view of a first embodiment of an acoustic attenuation member suitable for equipping the unitary module and the breathing assistance device;

is a sectional view of a second embodiment of an acoustic attenuation member capable of equipping the unitary module and the breathing assistance device.

The features, variants and different embodiments of the invention may be associated with each other, in various combinations, insofar as they are not incompatible or exclusive with respect to each other. In particular, variants of the invention may be imagined comprising only a selection of characteristics described below in isolation from the other characteristics described, if this selection of characteristics is sufficient to confer a technical advantage and/or to differentiate the invention. compared to the prior art.

In the following description, the terms "longitudinal", "transverse" and "vertical" refer to the orientation of a breathing assistance device according to the invention along longitudinal L, vertical V and transverse axes. T of a reference L, V, T illustrated in the figures. A horizontal plane is defined by the longitudinal L and transverse axes T, perpendicular to the vertical axes V, and can correspond to a plane parallel to the ground depending on the positioning of the breathing assistance device on a flat surface, without this being limiting of the invention.

In addition, the terms “upstream” and “downstream” used in the rest of the description refer directly to the direction of the circulation of air or gas within a circuit considered. More specifically, the term “upstream” of an object in the description will refer to the start of air circulation in the circuit considered, i.e. before the object in question. Conversely, the term "downstream" of an object in the description will refer to following the circulation of the air in the circuit considered, i.e. after the object in question.

As shown on the , a breathing assistance device 1 comprises at least one housing 2 in which several components are housed, including at least one device for circulating air, comprising a motorized fan, and two acoustic attenuation members respectively arranged upstream and downstream of this motorized fan. The particular arrangement of these acoustic attenuation members on either side of the motorized fan, and in particular their arrangement along axes of elongation which are substantially perpendicular to each other, will be described in more detail below.

The housing 2 generally takes the form of a six-sided rectangular parallelepiped. More particularly, the casing 2 comprises two longitudinal walls 6 extending in a plane in which a longitudinal axis L is inscribed, forming the main extension axis of the casing 2, and a vertical axis V perpendicular to the longitudinal axis L. The two longitudinal walls 6 extend along the longitudinal axis L between two transverse walls 8a, 8b which for their part extend parallel to the vertical axis V and to a transverse axis T perpendicular to the longitudinal axes L and vertical V. The two longitudinal walls 6 and the two transverse walls 8a, 8b extend along the vertical axis V between an upper wall 10 and a lower wall 12, these lower 12 and upper 10 walls extending in planes in which the longitudinal L and transverse T axes are inscribed.

The box 2 comprises at least one display device 14 positioned at the level of one of the two transverse walls 8a, 8b. To facilitate understanding of the invention, it is defined that the transverse wall on which the display device 14 is positioned is positioned at the front of the housing 2 along the longitudinal axis L, the other transverse wall thus being at the rear of the case 2. A front transverse wall 8a and a rear transverse wall 8b are thus defined, the term "transverse wall 8a, 8b" possibly referring indiscriminately to one or the other of the transverse walls 8a, 8b in the absence of the indication "front" or "rear" in the following description.

The display device 14 is here a screen on which at least information related to the breathing assistance device 1 is displayed. The display device 14 can also be a tactile communication interface, or touch screen, with which a practitioner can interact directly by tactile contact with the respiratory assistance device 1.

The casing 2 houses an inspiration circuit 16, a gas inlet pipe 18 and an expiration circuit 20 extending in the internal volume of the casing 2. The inspiration 16 and expiration 20 circuits, as well as than the gas inlet pipe 18, are particularly visible on the because one of the longitudinal walls 6 of the casing 2 has not been shown in this figure, making visible certain components of the respiratory assistance device 1 extending into the internal volume of the casing 2.

The inspiration 16 and expiration 20 circuits here each comprise a connection end piece 22 to a pipe connecting the inspiration 16 or expiration 20 circuit to a patient, these pipes not being shown here. This connection end piece 22 extends through the front transverse wall 8a, to place the pipe connected to the patient in air communication with the inspiration 16 or expiration 20 circuit.

The gas inlet pipe 18 also comprises a connection member 24 extending through the front transverse wall 8a, opening out inside the breathing assistance device 1. This connection member 24 makes it possible to connect the gas inlet pipe 18 of the breathing assistance device 1 to a gas distribution system, external to the breathing assistance device 1. The gas inlet pipe 18 comprises a pipe 26 connecting this connection device 24 to the inspiration circuit 16.

The inspiration circuit 16 is configured to distribute a flow of air to the patient, thus simulating the natural inspiration of a human being, the gas inlet pipe 18 enriching the air supplied to the patient with a gas, such as oxygen for example. The exhalation circuit 20 makes it possible to manage the expulsion of air from the patient like the natural exhalation of a human being. The inspiration 16 and expiration 20 circuits of the respiratory assistance device 1 thus operate in cooperation with each other to produce artificial respiration close to the natural respiration of a human being.

For this, the inspiration circuit 16 comprises at least one device 28 for circulating air through the inspiration circuit 16 to the patient, and an inspiration control valve 30 authorizing or blocking the circulation. air into inspiration circuit 16. Similarly, exhalation circuit 20 includes an exhalation control valve 32 allowing or blocking the flow of air through exhalation circuit 20, each control valves 30, 32 extending here mainly along the transverse axis T. Each control valve 30, 32 can thus assume a circulation position and a blocking position. When a control valve 30, 32 is in a circulation position, it allows the free circulation of air in the circuit on which the control valve concerned is installed. Conversely, when a control valve 30, 32 is in a blocking position, it prevents the circulation of air in the circuit on which the control valve concerned is installed.

The alternating change of position of the inspiration 30 and expiration 32 control valves makes it possible to control the patient's inspiration and expiration. More particularly, the inspiration control valve 30 is placed in a circulation position when the patient must inspire, the expiration control valve 32 then being placed in a blocking position, so that the air sent to the patient does not circulate in the exhalation circuit 20. Conversely and when the patient has to exhale, the inspiration control valve 30 is placed in a blocking position, preventing a supply of air to the patient, and the control valve expiration 32 is placed in a circulation position allowing the patient to expel the air contained in his respiratory system.

We will now describe the inspiration circuit 16 in more detail, with particular reference to FIGS. 1 and 2.

The inspiration circuit 16 includes at least one air inlet 44 and the air circulation device 28, which includes a motorized fan whose operation is controlled to force air to circulate through the inspiration circuit. inspiration 16 from the air inlet 44. The inspiration circuit 16 further comprises an air mixing member 48 arranged at the outlet of the circulation device, the air being mixed with a gas coming from the gas inlet pipe 18, the inspiration control valve 30 of the air/gas mixture of the inspiration circuit 16 and the connection end piece 22 intended to be connected to a patient.

The inspiration circuit 16 further comprises a first duct 52, forming an air intake duct which connects the air inlet 44 to the circulation device 28, and a second duct 64, forming a air outlet which connects the circulation device 28 to the mixing device 48.

The air inlet 44 consists of a mouth of the inspiration circuit 16 open to the outside of the respiratory assistance device 1 at the level of one of the walls of the casing. Advantageously, an air-filtering device is arranged at the level of the air inlet 44 of the inspiration circuit 16 to filter the particles in suspension in the air drawn into the inspiration circuit 16.

The circulation device 28 consists of a motorized fan, which includes a wheel 61 visible on the and housed in a volute 60, the wheel being connected to an electric motor 62 capable of driving the wheel around an axis of rotation.

The electric motor 62 is here an axial motor comprising a cylindrical casing which extends mainly along the axis of rotation of the fan, and it should be noted that this electric motor can in particular, as is detailed in the , be held in position relative to the volute by means of a motor support 63, without this being limiting of the invention.

The wheel of the circulation device is particularly visible on the and it is configured, once rotated at high speeds, to draw in air from outside the respiratory assistance device 1 through the first duct 52 to expel it into the part of the inspiration circuit 16 disposed downstream of the circulation device.

The volute 60 has a housing for receiving the impeller, and this volute comprises on the one hand a front face in the center of which extends an inlet orifice, and on the other hand a peripheral annular wall in which extends a exit hole. In other words, the volute has an axial inlet and a radial outlet.

As can be seen in FIGS. 1 and 2, the first duct 52 opens directly into the volute 60 of the circulation device 28 at the level of the inlet orifice formed in the front face of the inlet face of the volute. 60, so that the air flowing in the first duct 52 is able to emerge in the volute 60.

The first duct 52 is arranged mainly horizontally. The first duct 52 and the circulation device 28 are arranged so that the axis along which the axial motor extends and the axis of rotation of the wheel coincide, or at least parallel, with an axis defining mainly the elongation of the first duct 52. In the configuration illustrated, the first duct 52 extends more particularly in a longitudinal direction, in the extension of the inlet of the volute.

At the outlet of the air circulation device 28, the second duct 64 communicates with the radial outlet and it extends initially in a substantially vertical direction, that is to say in a direction substantially perpendicular to the horizontal arrangement of the first duct, and in particular perpendicular to the longitudinal direction illustrated here.

The inspiration circuit 16 comprises according to the invention a first acoustic attenuation member 45 arranged upstream of the circulating device 28, that is to say between the air inlet 44 and the putting device. in circulation 28, and a second acoustic attenuation member 46 arranged downstream of the circulation device 28, that is to say between the circulation device 28 and the inspiration control valve 30 blocking or not the passage of air towards the end piece 22. The first acoustic attenuation member 45 is arranged on the first duct 52 and the second acoustic attenuation member 46 is arranged on the second duct 64.

Each acoustic attenuation member here has the function of reducing the operating noises of the circulation device 28, and in particular the mouth noises, that is to say the noises generated by the passage of air at the level of the connection of the circulation device with the first conduit 52 and the second conduit 64.

Each acoustic attenuation member generally has the shape of a cylinder of revolution extending mainly around an axis of elongation corresponding to the axis of revolution of the cylinder, with, as will be detailed below, a tube internal passing through the cylinder and in which air is able to flow towards or from the circulating device according to the downstream or upstream position of the acoustic attenuation member.

According to the invention, the first acoustic attenuation member 45 extends mainly along a first axis of elongation A1 and the second acoustic attenuation member 46 extends mainly along a second axis of elongation A2, and these two elongation axes are substantially perpendicular.

As represented in FIGS. 1 and 2, the first axis of elongation A1 along which the first acoustic attenuation member 45 mainly extends is parallel to the general elongation orientation of the first duct 52, according to an orientation horizontal and here more particularly longitudinal. The second axis of elongation A2 along which extends the second acoustic attenuation member 46 extends parallel to the general orientation of elongation of the second duct 64, according to a vertical orientation and therefore perpendicular to the orientation of the first acoustic attenuation device.

In the configuration illustrated, the circulation device is such that the axis along which the axial motor extends, and the axis of rotation of the wheel, coincide, or at least parallel, with the first axis of elongation A1 of the first acoustic attenuation member, here in a longitudinal direction.

It is understood in the foregoing that the horizontal arrangement of the air intake duct formed by the first duct 52 connecting the air inlet to the motorized fan implies a horizontal arrangement of the acoustic attenuation member arranged on this duct admission, and therefore according to the invention a vertical arrangement of the second acoustic attenuation member. In particular, the first acoustic attenuation member arranged upstream of the circulation device can, as illustrated, extend along the upper horizontal wall 10 of the housing, the second acoustic attenuation member extending between the device circulation 28 and the lower horizontal wall 12 of the housing.

The air inlet 44 of the inspiration circuit 16 is here arranged at the level of one of the longitudinal walls 6 of the casing 2, in the vicinity of the front transverse wall 8a, so that the inlet duct and the first acoustic attenuation member extend longitudinally along the corresponding longitudinal wall to be connected to the circulation device. It should be noted that this arrangement is not limiting since the acoustic attenuation members have a perpendicular arrangement between them. By way of example, an air inlet of the inspiration circuit could be arranged on this same longitudinal wall, in the vicinity of the rear transverse wall 8b this time, so that the first duct 52 and the first attenuation member acoustics take a transverse orientation to connect the volute. The mainly horizontal arrangement of the first acoustic attenuation member would in this case be retained and this horizontal arrangement would indeed allow an arrangement substantially perpendicular to the second acoustic attenuation member.

In the example illustrated schematically on the , the inspiration circuit 16 further comprises an accumulation device 50 for at least the gas, such an accumulation device 50 being associated with the second acoustic attenuation member 46 by being arranged aeraulically between the device for circulation 28 and the mixing device 48 to prevent the rise of gas towards the circulation device when the associated valve blocks the passage of enriched air in the inspiration circuit towards the patient. The damping device forms a buffer zone whose volume is configured to be able to accommodate a quantity of gas emitted by the gas inlet pipe into the mixing member when the control member of the inspiration control valve is in a blocking position and during a maximum exhalation time, it being understood that the latter corresponds to the maximum time during which the inspiration control valve is in a blocking position, the exhalation control valve then being in a position traffic.

In the embodiment illustrated in the figures, and as is particularly visible in , the buffer zone is formed by a chamber concentrically surrounding the second acoustic attenuation member. By way of non-limiting example, this chamber may have a total volume of approximately 1 m3. The second conduit 64 is configured to pass successively through the second acoustic attenuation member and the accumulation device 50. It should however be noted that the present embodiment is not limiting of the invention and that the shape of the accumulation device as well as its arrangement with respect to the damping device could be modified without departing from the context of the invention, for example by providing a duct of square section which extends in a spiral around the attenuation member acoustic.

It is notable that only the second acoustic attenuation member 46 is associated with an accumulation device, due to its position downstream of the air circulation device.

We will now describe in more detail the acoustic attenuation members and the air circulation device, with reference to Figures 2 to 5.

Especially on the , it is visible that the circulation device 28, the first acoustic attenuation member 45 and the second acoustic attenuation member 46 form an assembly arranged in a corner of the housing, with more particularly the circulation device 28 arranged in the corner, the first acoustic attenuation member 45 arranged horizontally, along the upper wall 10, and the second acoustic attenuation member 46 arranged vertically, along the rear transverse wall 8b, and therefore perpendicular to the first acoustic attenuation member 45. Such an arrangement makes it possible to optimize the space present within the housing, and in particular makes it possible to reduce the size of the breathing assistance device with a number of identical components inside the housing . It should be understood that to facilitate the reading of this , the components likely to equip the case have not been shown.

Furthermore, and as will be detailed just below, this makes it easier to fix the acoustic attenuation members and the circulation device 28 to one and/or the other of the walls delimiting the housing, and therefore to limit the number and/or the bulk of the parts to be provided for fixing these parts in the housing.

We will describe in more detail below the manufacturing means implemented to produce the acoustic attenuation members, and the shape of these acoustic attenuation members which can result therefrom, it being understood that the perpendicular or substantially perpendicular arrangement of the acoustic attenuation members is independent of the structure that they may have one and/or the other.

With reference to Figures 2 to 5, we will now describe a particular configuration of the respiratory assistance device with the circulation device and the acoustic attenuation members forming a unitary module, which can be fixed in one piece. on the device housing.

The unitary module 100 comprises here in particular the circulating device 28, each of the acoustic attenuation members 45, 46 mentioned above, and a casing 102 which is configured to allow the fixing of the unitary module 100 on the housing 2 of the device. breathing assistance, and which is configured to freeze the position of each of the acoustic attenuation members 45, 46 with respect to the circulation device 28.

The housing 102 comprises at least a first fixing plate 104 on which is fixed the first acoustic attenuation member 45 and a second fixing plate 106 on which is fixed the second acoustic attenuation member 46. Each acoustic attenuation member is fixed to the corresponding crankcase fixing plate so that its axis of elongation A1, A2 is substantially perpendicular to the plane defined by said fixing plate. In other words, in the example illustrated, the first fixing plate 104 of the casing is substantially vertical and the second fixing plate 106 of the casing is perpendicular to this first fixing plate 104 and substantially horizontal.

The first fixing plate 104 and the second fixing plate 106 each comprise an orifice for passage of a fluid connection end piece 105, said connection end piece being formed in the extension of an internal tube, here not visible, of each organ. acoustic attenuation 45, 46.

This results in an arrangement in which the fluid connection endpiece associated with each acoustic attenuation member is hydraulically connected, here by a hose 450, 460, to an inlet or outlet mouth of the volute of the device for circulation 28.

Each acoustic attenuation device is made integral with a fixing plate of the casing. More particularly, the first acoustic attenuation member 45 is secured to the first casing fixing plate 104 and the second acoustic attenuation member 46 is secured to the second casing fixing plate 106. To this end, each acoustic attenuation member 45, 46 has a fixing wall 451, 461, from which projects the previously mentioned connection end piece, and which has at least one fixing element peripherally. Each acoustic attenuation member 45, 46 is made integral with a fixing plate of the casing via at least one fixing means 108, which may in particular consist of clamping means configured to pass through an orifice, forming the fixing element made in the fixing wall, and a hole formed in the corresponding fixing plate of the casing, the fixing wall 451, 461 being pressed against the fixing plate of the corresponding casing 104, 106 once the clamping means implemented.

By way of non-limiting example, the clamping means may consist of a bolt formed of a screw and at least one nut, the screw possibly being integral with the fixing plate of the casing against which the acoustic attenuation device.

As may have been specified previously, the circulation device and the acoustic attenuation members are arranged in a corner of the housing, with the motorized fan forming the circulation device which is framed by an attenuation member acoustic, or silencer, upstream and an acoustic attenuation device, or silencer, downstream.

More particularly, in the context of a unitary module 100 fixing the positions of the attenuation members on either side of the motorized fan, the casing 102 is arranged in the corner of the corresponding casing with the first fixing plate 104 arranged parallel to the rear transverse wall 8b of the casing 2 and with the second fixing plate 106 arranged parallel to the upper longitudinal wall 10, along which the first duct 52 extends.

The housing 102 further comprises a third fixing plate 114 substantially parallel to the second fixing plate 106 and intended to be against the upper wall 10, and a fourth fixing plate 116 substantially parallel to the first fixing plate 104 and intended to be be against the rear transverse wall 8b. The third fixing plate 114 extends in the extension of the first fixing plate 104, substantially perpendicular to the latter.

Fourth attachment plate 116 extends between third attachment plate 114 and second attachment plate 106 to close the frame and provide substantial rigidity to the unitary module. As can be seen in Figures 2 to 4, the casing thus comprises four fixing plates each participating in giving the casing the shape of a frame, with a profile closed and open transversely on each side. In a particular embodiment of the invention, a damping material, for example foam, can be injected into the volume defined by this closed frame.

As seen on the , or a longitudinal wall has been removed to make the inside of the case visible, the first and fourth fixing plates comprise lugs for holding in position 118 which are intended to be in contact with one of the longitudinal walls to ensure the transverse positioning of the unit module 100 between the longitudinal walls of the housing.

The four fixing plates can be made in one piece, the casing being obtained by successive foldings to form the closed profile of the frame mentioned above. In the example illustrated, the third fixing plate 114 is produced separately from the other plates, the first fixing plate 104, the second fixing plate 106 and the fourth fixing plate 116 forming the same assembly, the shape of which is obtained by folding successive. The third fixing plate 114 is then made integral with the other plates by welding, gluing or any suitable fixing means, in particular via deflection edges 115 of appropriate shapes and dimensions to partially cover the first fixing plate and the fourth fixing plate.

The third fixing plate 114 has the function of allowing the fixing of the casing, and therefore of the unitary module 100, on the housing 2 of the respiratory assistance device. In the example illustrated, the third fixing plate 114 of the casing makes it possible to ensure the fixing of the unitary module 100 on the casing by means of a sheet 120 arranged against the upper wall 10 of the casing. This sheet 120, shown alone without the upper wall 10 in FIGS. 3 to 5, can in particular make it possible to attach handles for gripping the respiratory assistance device.

The third plate is here fixed indirectly on a wall of the box, namely the upper wall, due to the intermediate presence of the sheet 120, but it is appropriate that one could provide a direct fixing on the wall of the box without leaving the context of the invention. Fastening members 122 are arranged between, on the one hand, the wall of the box, if necessary the intermediate sheet 120, and, on the other hand, the third plate 114 of the housing of the unitary module 100. These fastening members may in particular comprise means damping intended to reduce the transmission of vibrations from the circulating device to the housing of the respiratory assistance device.

In the example illustrated in Figures 2 and 3, this third fixing plate 114 also has the function of fixing the circulation device 28, in particular via a cradle 29 which is mounted on the third fixing plate 114 by the intermediate damper blocks 119. It should be noted that this example does not limit the invention, and that, as has been illustrated by way of example on the , the circulation device can be held between the acoustic attenuation members without the need for a cradle.

Such a unitary module facilitates the assembly of the respiratory assistance device in that it allows a single assembly operation on the housing, the parts of the unitary module being assembled at a distance from the housing.

The advantages in terms of simplification of assembly will in particular be mentioned in a non-limiting manner by describing an example of a method for assembling the breathing assistance device.

The unitary module is advantageously assembled in the housing once the other components, for example the inspiration and expiration control valves 30, 32, or any batteries so as to allow easy assembly of these components.

At the same time, the unitary module is assembled with, on the one hand, the fixing of each of the acoustic attenuation members on the fixing plate of the housing which is specific to it, namely the first fixing plate and the second fixing plate, and the other by fixing the circulating device 28 on the fixing plate which is intended for it, namely here the third fixing plate. Here again, this assembly facilitates assembly with unobstructed access for the operator. The third fixing plate is then attached and welded to the rest of the fixing plates, the use of connection hoses 450, 460 for the fluidic connection of the acoustic attenuation members with the circulation device making it possible not to hold account of assembly tolerances.

The unitary module 100 thus formed is then attached to the casing and fixed only initially at the level of the third fixing plate 114, here on the upper wall 10 via the intermediate sheet 120 if necessary. The operator can then make an additional attachment of the acoustic attenuation devices to the housing. Finally, the operator connects the acoustic attenuation devices respectively to the first conduit 52 and to the second conduit 64.

As mentioned above, each silencer, or acoustic attenuation device, is configured to attenuate the operating noises of the motorized fan forming the air circulation device, by passing the air intended to penetrate or exit from the motorized fan via a perforated tube to an enclosed chamber filled with acoustically absorbent material. More particularly, the silencers are intended to attenuate the noises commonly called mouth noises, namely noises composed of high frequencies, generated by the passage of the blades of the wheel of the motorized fan in front of the orifice forming the inlet or the outlet of scroll of the circulating device 28 and transiting by air.

Each of the acoustic attenuation members 45, 46 thus comprise, as may have been mentioned previously, a cylindrical casing 452, 462, forming a hollow part of revolution around an axis of elongation A1, A2, and a tube internal perforated 454, 464 passing through the cylindrical envelope and connected at each end to the air duct 52, 64 to which the acoustic attenuation member is connected. Each acoustic attenuation member also comprises a layer of acoustic absorption material, here not shown, to make visible the internal tube that the acoustic absorption material surrounds by filling the cavity formed inside the cylindrical envelope, with so as to absorb at least part of the acoustic waves produced by the operation of the circulating device 28 and leaving the inner tube through the various perforations.

As seen on the , the first acoustic attenuation member 45, disposed upstream of the circulating device 28, has larger dimensions than those of the second acoustic attenuating member 46, disposed downstream of the circulating device 28. This oversizing of the first acoustic attenuation member 45 is in particular due to the fact that it must attenuate the muzzle noise at the inlet of the respirator, at the level of the air inlet 44, whereas the acoustic waves which propagate downstream of the circulation device towards the outlet of the respiratory assist device are naturally mitigated by the connection of the respiratory assist device to the patient.

The possible difference in dimensions of the acoustic attenuation members can in particular consist of a multiplier ratio ranging from 1 to 2. In other words, one dimension of the first acoustic attenuation member 45 can be up to twice greater than the corresponding dimension of the second acoustic attenuation member 46.

More particularly, the first acoustic attenuation member 45 may have a cylindrical casing 452 whose average diameter is of the order of 120mm and whose main dimension, along the first axis of elongation A1 is of the order of 200mm . And the second acoustic attenuation member 46 may have a cylindrical casing 462 whose average diameter is of the order of 95mm and whose main dimension, along the second axis of elongation A2 is of the order of 100mm.

In each of these sound attenuation members, the sound absorption material may in particular consist of a reticulated foam, of the polyester type, chosen in particular according to these acoustic qualities, and its ISO 10993-5 certified biocompatibility, necessary for this type of medical application.

Each of the acoustic attenuation members can be produced by additive manufacturing, for example by three-dimensional printing. Such an embodiment may in particular be advantageous for the manufacture of the downstream acoustic attenuation member, that is to say the one equipped with an accumulation device if the latter is made with a buffer zone formed by an arrangement in a spiral of a conduit such as that could be evoked.

Figures 5 and 6 make visible the detail of a first embodiment of the acoustic attenuation members made at least partially in additive manufacturing. According to this first example, four parts are assembled together to form an acoustic attenuation device. In particular, three parts are produced by additive manufacturing to form the outline of the acoustic attenuation member, among which the fixing wall 451, 461, the cylindrical casing 452, 462 of elongation axis A1, A2, and a closing wall 453, 463 arranged parallel to the fixing wall at the opposite end of the acoustic attenuation member. The two walls at the end have an orifice to be passed through by the perforated inner tube 454, 464 produced elsewhere.

As can be seen in FIGS. 2 and 4, the closing wall 453 of the first acoustic attenuation member 45 may include a retaining lug 455, capable of being secured to a wall of the box, directly or indirectly via the sheet metal. 120, so as to support the weight of the first acoustic attenuation member and avoid a deflection which could force too strongly the first duct 52 on which the first acoustic attenuation member is arranged.

On the , there is illustrated a second embodiment of the acoustic attenuation member 45, 46, which differs from what was previously described in that it is formed of only two parts. These two parts can each be made in additive manufacturing, so that the entire silencer is made in this way. A first part 201 forms a single piece of the fixing wall 451, 461 and the cylindrical casing 452, 462, and a second part 202 forms a single piece of the closure wall and the perforated tube 454, 464. closure wall 453, 463 has on its inner face, from which the perforated tube protrudes, a collar 204 around which the cylindrical casing is centered when the two parts are assembled. During this assembly, it is ensured that the inner tube 454, 464 of the second part 202 crosses the fixing wall 451, 461 of the first part, and the two parts are glued or welded together once the cylindrical envelope in abutment against the closing wall. It should be understood that what has been described above regarding the arrangement of the acoustic attenuation members is equally valid for acoustic attenuation members made according to the first exemplary embodiment and according to the second exemplary embodiment.

The foregoing description clearly illustrates the means implemented by the invention to achieve the aims it has set itself, namely to offer an assembly formed by a circulation device and attenuation members. acoustic which is easy to integrate into a breathing assistance device, on the one hand to facilitate its manufacture and therefore limit the cost of obtaining it, and on the other hand to limit the size of this assistance device to breathing while maintaining appropriate dimensions of the motor and acoustic attenuation devices to ensure high performance in terms of airflow pressure and acoustics.

The invention cannot however be limited to the means and configurations described and illustrated here, and it also extends to any equivalent means or configuration described and illustrated here, and it also extends to any equivalent means or configuration and to any combination technique operating such means. In particular, the shapes of the acoustic attenuation members, of the air circulation device and of the casing making it possible to form with these components a unitary module could be modified without departing from the context of the invention, provided that their arrangement allows a substantially perpendicular arrangement of the acoustic attenuation members on either side of the air circulation device.

Claims (15)

Device for assisting the respiration (1) of a patient, comprising at least one inspiration circuit (16), an expiration circuit (20), as well as a device for circulating (28) the air in the inspiration circuit (16), characterized in that it comprises two acoustic attenuation members (45, 46) arranged one upstream and the other downstream of the circulation device with respect to in the direction of air flow in the inspiration circuit, each acoustic attenuation member extending mainly along an axis of elongation (A1, A2) so that these axes of elongation are perpendicular l one relative to the other. Breathing assistance device (1) according to claim 1, characterized in that it comprises a casing (2) within which a first acoustic attenuation member (45) arranged upstream of the circulation device ( 28) is arranged horizontally and within which a second acoustic attenuation member (46) arranged downstream of the circulating device (28) is arranged vertically. Breathing assistance device (1) according to Claim 2, characterized in that the first acoustic attenuation member (45) arranged upstream of the circulation device (28) is arranged longitudinally, along a longitudinal wall (6) of the casing (2). Breathing assistance device (1) according to one of Claims 2 or 3, characterized in that the first acoustic attenuation member (45) arranged upstream of the circulation device (28) extends along the along an upper horizontal wall (10) of the housing, the second acoustic attenuation member (46) extending between the circulation device (28) and a lower horizontal wall (12) of the housing. Breathing assistance device (1) according to one of the preceding claims, characterized in that it comprises a casing (102) on which the circulation device is fixed, the acoustic attenuation members (45, 46) being respectively fixed on a fixing plate (104, 106) of the casing (102) so that the acoustic attenuation members (45, 46), the circulation device (28) and the casing (102) form a unitary module (100). Breathing assistance device (1) according to the preceding claim, in combination with claim 2, characterized in that the unitary module (100) is fixed to a wall (10) of the casing (2) by means of 'a fixing plate (114) of the housing (102). Breathing assistance device (1) according to the preceding claim, characterized in that the casing is fixed to the casing by means of a casing fixing plate separate from the casing fixing plates on which the attenuation are fixed. Breathing assistance device (1) according to one of Claims 5 to 7, characterized in that a damping material is injected into the volume defined by the housing of the unitary module. Breathing assistance device (1) according to one of the preceding claims, characterized in that at least one acoustic attenuation member (45, 46) comprises a cylindrical envelope inside which extends a perforated inner tube (454, 464) fluidly connected to the inspiration circuit (16). Breathing assistance device (1) according to the preceding claim, characterized in that the internal tube (454, 464) is connected to an inlet or outlet mouth of a volute (60) of the device for circulation (28) via a flexible connection (450, 460). Breathing assistance device (1) according to one of the preceding claims, characterized in that the acoustic attenuation members (45, 46) have different dimensions, one dimension of the acoustic attenuation member (45 ) arranged upstream of the circulating device (28) being up to twice greater than a corresponding dimension of the acoustic attenuation member (46) arranged downstream of the circulating device (28). Breathing assistance device (1) according to one of the preceding claims, in combination with claim 9, characterized in that the acoustic attenuation member (45) arranged upstream of the circulation device (28 ) has a cylindrical casing (452) whose average diameter is of the order of 120mm and whose main dimension, along its axis of elongation A1, is of the order of 200mm. Breathing assistance device (1) according to one of the preceding claims, in combination with claim 9, characterized in that the acoustic attenuation member (46) arranged downstream of the circulation device has a cylindrical casing (462) whose average diameter is of the order of 95mm and whose main dimension, along its axis of elongation A2, is of the order of 100mm. Breathing assistance device (1) according to one of the preceding claims, characterized in that the acoustic attenuation member (45, 46) comprises on the one hand three parts respectively produced by additive manufacturing means and assembled to form a cylindrical assembly and on the other hand an inner tube (454, 464) produced separately and secured to the cylindrical assembly. Breathing assistance device (1) according to one of the preceding claims, characterized in that the inspiration circuit (16) comprises a member (48) for mixing the air coming from the circulation device ( 28) with a gas coming from a gas inlet pipe (18), and in that an accumulation device (50) is arranged aeraulically between the acoustic attenuation member (46) arranged downstream of the circulation device (28) and the mixing device (48).