Portable device for inhalation of warm, humidified air

The present invention relates to devices or appliances used against hypothermia in humans by inhalation of hot air and it seeks, principally, the devices can be called notebook or autonomous, that is, -dire those intended for use at the scene of the accident.

To fight against hypothermia experiments helped to highlight the interest of the heat input to the accident by the pulmonary route.

Indeed, the human body can be considered to be divisible into two parts from the viewpoint of its the rmo-regulation. The most sensitive or thermal core part is that the temperature is normally set at 37 ° C. This part of the body including the brain, heart, liver, etc ... The second part is that which can be seen as peripheral to the first for which variable temperatures may be accepted, given the organic functions to maintain and exchange capabilities with the environment .. the second part comprises essentially the muscles and limbs.

A significant temperature difference in these two parts of the body can therefore be accepted, however, as the heat slug condition does not fall below 30 ° C. Indeed, below this temperature, heart malfunctions and risk to stop.

Experiments have shown that the heat input must be obligatorily insured thermal core of the human body, so as to maintain the vital organs considered in optimal operating conditions, to fight against localized hypothermia territory device or the second part.

It was found that the hot air supply through the lungs directly, possible to achieve this goal, provided that the hot air is, moreover, sufficiently laden with moisture to avoid the risk of bronchospasm and airway dryness.

To ensure the provision of hot and humid air, to fight against hypothermia, several proposals were made.

One of them is to heat by a system external combustion stove type, a container of water to produce a hot water vapor that is inhaled by the subject.

Such a method is dangerous, because the water vapor can not be controlled or regulated in temperature and may then, in some cases to be responsible for respiratory tract burns.

Furthermore, the operation of such a device requires a horizontal stable position which can not be practically adopted in practice, since a risk of hypothermia is, most of the time, the result of an accident in a place or difficult to access or cluttered site.

In addition, the use of a stove, usually with fuel gas, a source of danger and significant accidents.

A second proposal is based on the exothermic reaction of lime placed in the presence of water. Such exothermic reaction does not control or regulate the temperature accurately the reaction gas and therefore does not answer to the problem which involves, necessarily, the supply of a mixture or a humidified air temperature controlled constant to place the subject in a receptive state of relaxation and the most favorable expectation in the fight against hypothermia he suffered accidentally.

It is understood, moreover, that such a proposal is difficult to implement practically in the case of road accidents or rescues in the mountains. Parailleurs, such a technique does not have a sufficient operating autonomy for the practical struggle against hypothermia.

A third proposal can be considered on the basis of the teaching disclosed by FR-A-2162340 although it does not, strictly speaking, the fight against hypothermia in humans, but is the medical treatment of respiratory tract.

According to this document the recommended treatment device comprises a tubular insulating housing defining an inlet and an air outlet, an internal circulation circuit in successive cusps and containing a heating unit disposed in the last part of the circuit and a means of humidification placed upstream of the heating unit. the air temperature control means are also provided.

Such a device does not appear suited to the area covered by the invention because, inter alia, it ranks among the static character devices operating by depression resulting from the intake by the subject. In addition, the series of humidifying means and the heating unit does not appear appropriate for the provision of air properly heated, humidified and controlled for the application to the fight against hypothermia of 'man.

The present invention aims to remedy the disadvantages attached to the current proposals known to fight against hypothermia by inhalation of warm moist air and, to this end, provides a portable device with a wide operating range and can be used in all the positions.

The object of the invention is to provide an apparatus to operate effectively in a large temperature range and under varying atmospheric pressure, for delivering a hot, humid air controlled to a maximum temperature, optimal for the warming function of the thermal core and without any risk to the respiratory tract.

Another object of the invention is to provide an easily handled apparatus by a not specially trained personnel and having a resistance, especially to shocks, very high.

Another object of the invention is to provide a compact device, so as to be fed, raised, engaged or placed in any location in which a human body is already past, in order to enable all rescue operations a human being placed in hypothermia conditions following an accident.

The object of the invention is particularly chosen in design, so as to represent a rescue equipment in the installation accidents and accidents in road traffic or self-road or maritime among others.

To achieve the above objects, the object of the invention is characterized:<ul><li>- In that it comprises:<ul><li>a hose in communication with the outlet of the housing which channels the air towards a buccal orifice and which comprises discharge means and a probe for measuring the temperature of the air,</li><li>an air circulation formatting device in an axial direction to the housing and housed in a compartment of the latter communicating with the inlet port,</li></ul></li><li>- In that the heating unit and air humidification is situated between the compartment outlet and I, so that the air flow duct extends between the compartment and the orifice Release,</li><li>- And in that the control means controls the supply of electric resistors beam and comprising the probe for measuring the air temperature and two thermostats associated with unit.</li></ul>

Various other characteristics appear from the description given below with reference to the accompanying drawings which, as non-limiting examples, embodiments of the object of the invention.<ul><li>FIG. 1 is a schematic elevation sectional view of the object of the invention.</li><li>FIG. 2 is a cross section taken along the line II-II of FIG. 1.</li><li>FIG. 3 is a block diagram of one of the constituent elements of the object of the invention.</li><li>FIG. 4 is a cross section similar to FIG. 2 but illustrating an alternative embodiment.</li></ul>

According to FIGS. 1 and 2, the apparatus comprises a casing or housing 1 of generally tubular shape, closed at one transverse end by a wall 2 delimiting an air inlet 3. The opposite end of the housing or casing 1 has a port 4 of the air outlet, which is placed substantially on the geometric longitudinal axis of the housing or casing 1.

In one embodiment, the housing is formed by two concentric shells 1a and 1b, made of any material having good characteristics of mechanical strength and thermal insulation. These two casings 1a and 1b are joined together by a packing or filling 5 of insulating material, for example a material developed foam with open or closed cells, whose density is chosen so that it contributes to the obtaining high strength characteristics, is intimately linked to the opposite faces of concentric shells 1a and 1b.

According to a preferred construction, the housing or casing 1 comprises a main body 1, and a secondary body 1₂ designed as a lid. The secondary body 1₂ is mounted on the body 1_i by a hinge 6 and by at least one fastening device 7 of the conveyor type, for example.

The secondary body 1₂ defines the outlet port 4, which is bordered by a connector 8 which fits permanently or temporarily, a pipe 9 provided at its free end with a mouthpiece or mask 10. The pipe 9 comprises, immediately upstream of the nozzle 10, a bypass or venting air 11 whose passage section is controlled by a relief valve 12 responsive to the pressure in the pipe 9.

The main body 1, defining, from the transverse wall 2, a compartiement 13 separated by partial transverse partition 14 of a second compartment 15 delimited in part by the main body 1y and partly by the secondary body 1₂.

The compartment 13 contains a 16 air circulating device externally charged to the casing or housing 1 through the inlet 3. The device 16 may be constituted by an electric motor 17 fixed in any suitable manner, either directly or indirectementsur the transverse partition 2. the motor 17 includes an output shaft 18 extending in the axis of the body 1 and carrying an impeller 19 responsible for forcing air or a gas mixture in the direction of arrow f₁Through the wall 14 towards the compartment 15. The electric motor 17 is supplied with electric current, preferably from an independent source of distribution to which the apparatus of the invention is connected by a cord food.

In some cases, it may be provided, the compartment 13 of sufficient volume to accommodate a source of self-supply, such as a rechargeable battery.

The compartment 15 contains a unit 20 for heating and humidifying. The unit 20 comprises a beam 21 of electrical resistors 22, preferably lamellar type, which are maintained parallel to each other by webs 23 as shown in Figs. 1 and 2. The beam 21 is arranged to extend coaxially with the axis of the housing 1 on at least a portion of the length of the compartment 15. The beam 21 is electrically connected to control means 24 responsible for controlling the power resistors from the source of production or distribution of electricity. The means 24 are preferably constructed as an annular shape so as to be disposed in the compartment 13 surrounding the device 16 for circulating air.

The unit 20 further comprises a cartridge 25 of annular humidifying having an outer wall 26, of tubular shape, whose external diameter is provided to enable a just in the engagement compartment 15. For this purpose, the inner peripheral wall compartment 15 may include axial ribs 27 for centering and immobilization. The cartridge 25 further comprises, an inner wall 28 concentric with the wall 26 and defining a central recess 29 representing, by the time, a circulation duct for the air propelled by the device 16 and a housing for the beam 21. the inner peripheral wall 28 is the perforated type and can be constituted by a wire mesh, an expanded metal, perforated sheet or plate, etc ...

The peripheral walls 26 and 28 are joined together by transverse walls defining an annular recess filled with a mass M of fiber or the like, having a marked hydrophilic character. For example, the material M may consist of cellulose fiber formed into strands.

The cartridge 25 is shaped complementally to the volume of the compartment 15 so as to be axially immobilized therein between the partition 14 and the inner face of the secondary body 1₂, Which may, although this is not shown, stop bosses or, preferably, the reported buffer elastically deformable material.

The regulating means 24, including a schematic illustration is given by way of example in FIG. 3, comprise a probe 30 for measuring the air temperature. According to the invention, this sensor 30 is disposed at the center of the pipe 9 close to the nozzle 10 and, in any case, slightly upstream of the bypass or venting air 11. The regulating means 24 comprise also a first thermostat 31 disposed in the compartment 15 to assess the temperature of the air from unit 20 and via the pipe 9. the means 24 comprise, moreover, a second thermostat 32 enjoying the temperature developed by the beam 21 in the housing 29.

The thermostats 31 and 32 are arranged in series on the power circuit 33 of the beam supply 21 controlled by the control means 24. According to FIG. 3, these means 24 comprise more adjustable potentiometers 30a, 30b and 30c associated with comparators 34a, 34b and 34c representing security elements responsible for maintaining the integrity of the electrical connection between the probe 30 and the opening means -closure circuit 33.

It must be considered that the regulating means 24 could be realized in any other way different from the scope of those skilled in the art.

The apparatus described above operates as follows.

When switched on, the device propels 16, according to arrow f "of the air taken from the environment through the compartment 15. The firm also put under voltage circuit 33, so that the resistors 22 of the beam 21 are supplied with electricity. the air powered by the device 16 passes through the beam in which it is heated before entering the pipe 9.

The beam of temperature rise 21 causes the evaporation of the water retained by the material M of the cartridge 25. This evaporation takes place through the apertured peripheral wall 28 in the housing 29 so that the heated air is simultaneously loaded with water vapor, before entering the pipe 9.

The heated and humidified air is maintained at a constant temperature via the sensor 30 acting on the regulating means 24. Thus, the hypothermic subject may inhale through the mouthpiece 10, a constant temperature air regulated depending on heat input to be made, hypothermic conditions and adjustments made, especially by the potentiometer 30a.

Maintaining a constant temperature for air via the pipe 9, is provided by the sensor 30, regardless of the heat loss that may occur depending on the conditions of use along the path of the pipe 9. The flow air heated and humidified, surplus to consumption of the subject being treated, is discharged from the bypass 11 which may assume a simple function with the open air or a routing function of the excess part to warm the area body of the device or some members of the subject.

During operation of the apparatus, the evaporation of the M material layers, closest to the beam 21, maintains a radial inward migration of the water retained in the peripheral layers. This results in a progressive loss to maintain evaporation at a substantially constant rate and thereby produce a humidified hot air without substantial change of its humidity.

The layout of the cartridge 25 around the beam 21 allows to assume the mass M an additional function of thermal insulation to reduce the radial loss in combination with the insulating nature of the housing 1.

It should be noted that the device 16 and the regulating means 24 are disposed between the inlet 3 and the unit 20, so that these bodies are not subjected to a rise in temperature during operation of the unit, or to thermal stresses which might impair their operation, in particular over time.

The orifice 3 is preferably provided with a nozzle 35 associated with a valve 36 for adjusting its passage section. The tip 35 allows either direct extraction from the environment, or the connection to a source providing an appropriate gas mixture treatment to be conducted.

FIG. 1 shows that the cap 35 may comprise, also, two pipes 35a and 35b allowing, if necessary, to take air from the ambient environment, and at the same time, a supplementary gas mixture supplied by a make-up tank.

FIG. 4 shows, for comparison with FIG. 2, the inner peripheral wall 28 of the cartridge 25 may be associated with a sleeve 37 movable axially or angularly. Such a sleeve is the exchange surface between the cartridge and the actuator housing 29. It becomes possible, by the sheath, to initially adjust the humidifying rate of the discharged air and, where appropriate, to act in this way on the autonomy of operation of the device.

In the foregoing, it is indicated that the housing 1 is constructed in two parts to facilitate installation and change of the cartridge 25. It is also conceivable to provide the casing 1 with a filling orifice for refilling the cartridge by an external water supply.

FIG. 2 shows that the main body 1₁ and the secondary body 1₂ are extended outwards by gripping rings 38 and 39 constitutes, moreover, organs bumper protecting the connecting nozzles 35 and 38.

As is apparent from the above, the means used to constitute the object of the invention provide a compact, portable and capable of delivering a hot air temperature regulated and dampened significantly steadily.

Retaining the structural arrangement according to the invention, moreover, to have an operable in any position apparatus, being partially or completely autonomous, as the electrical energy required for its operation is taken from of an external source of distribution or is provided by an own battery.

Furthermore, the operating conditions of the apparatus are independent of the outside temperature and atmospheric pressure. In addition, thermal insulation ensured by the housing and the concentric arrangement of the cartridge 25 relative to the beam 21, provides, in difficult extreme conditions, hot air output temperature controlled and humidified for a long period without operation setting change.

The invention is not limited to the examples described and shown, as various modifications may be made without departing from its scope.