FR2546759A1 - Ventilation system, particularly for a ventilated protective overgarment - Google Patents

Abstract

Internal ventilation system comprising a tube 2 with an exhaust orifice 5, the tube 2 being connected to a pressurised fluid source 3. According to the invention, this system is noteworthy in that the exhaust orifice 5 of said tube 2 opens into at least one closed bag 7, 8, 9 made of a flexible porous material, the porosity of which is such that an excess pressure of fluid appears in said bag, the bag possessing a sufficiently great fluid diffusion surface area for the fluid passing through it to expand with an acceptable level of sound. Manufacture of internally ventilated protective garments.

Description

The present invention relates to a ventilation system, in particular for a tracksuit or a combination of protection with internal ventilation, for example intended to protect a person from contamination of a radioactive or biological nature.

The known protective tracksuits, intended to be donned over the clothes worn by the person wishing to protect themselves, are made of a soft waterproof material. The tightness obtained ensures effective protection against contamination. It follows that, due to the phenomena of skin respiration and sweating, the air in the internal volume of the tracksuit is quickly saturated with water since the latter cannot be evacuated. This results in an unpleasant sensation which makes it difficult to wear such tracksuits.

In addition, part - of the heat emitted by the body of the user which cannot escape, remains inside the tracksuit, which then increases the temperature of the air in contact and increases the glove of the user.

To try to remedy these drawbacks, it has already been thought to provide an internal ventilation device for such a tracksuit, generally comprising a flexible pipe connected at one of its ends to a source of pressurized fluid and opening at its other end to the inside said tracksuit. Of course, the tracksuit includes means for evacuating the ventilation fluid.

Such a ventilation device is very effective, however it has a disadvantage.

In fact, the pressurized fluid exiting from the end of the flexible pipe emits a high level of noise so that it results in discomfort from wearing such a ventilated tracksuit. It has been found that, in order not to interfere too much with the operator wearing such a protective tracksuit, it would be advisable to lower the noise level below 80dB, even with a high ventilation air flow (for example 400 lmn ) and a source of high pressure fluid (for example, a 7 bar compressed air network).

Of course, one could think of lowering the noise level by providing a regulator on the gas line
But then, the cost of the tracksuit (generally of the disposable type) would be appreciably increased and, in addition, the known mechanical expansion valves have a significant weight and bulk.

The object of the present invention is to remedy these disadvantages,
To this end, according to the invention, the ventilation system comprising a duct, provided with at least one exhaust orifice and connected to a source of pressurized fluid, is remarkable in that said exhaust orifice opens into at least one closed pocket made of a porous flexible material, for example a fabric of the canvas type, the porosity of which is such that an overpressure of the fluid appears in said pocket, the latter having a sufficiently large fluid diffusion surface so that the fluid passing through it expands with an acceptable sound level.

This produces a kind of particularly simple, lightweight, space-saving and inexpensive regulator.

The effect produced by the regulator according to the invention can be adjusted by appropriately choosing the porous flexible material, the size of the pocket and / or by providing several closed pockets, arranged around one another.

It is advantageous in this case that the diffusion surface of said pockets increases from the inside towards the outside. Thus, the overpressures in said pockets decrease from the inside towards the outside. A true multi-stage regulator is then obtained, making it possible to suppress the noise or at the very least to reduce it to an acceptable level.

Furthermore, it will be noted that the regulator is particularly advantageous since, in addition, its pocket or pockets form a filter for the ventilation fluid. Optionally, the material of at least one of said pockets can be chosen to exert a specific action of wire.

tration.

The figures of the appended drawing will make it clear how the invention can be implemented.

FIG. 1 partially shows an exemplary embodiment of ventilated protective tracksuit, associated with a ventilation system according to the invention.

FIG. 2 shows the internal end of the pipe of the ventilation system, equipped with the regulator according to the invention.

- Figure 3 is a section along line III-III of Figure 2.

The tracksuit 1, made of flexible synthetic material according to the invention, shown in FIG. 1, is crossed in leaktight manner by a flexible pipe 2, connected to a source 3 of a pressurized fluid.

As shown in FIG. 1, the end 4 of the pipe 2, internal to the tracksuit 1, is provided with an exhaust orifice 5 which opens into a pressure reducing device 6.

This is made up of three canvas pockets 7, 8 and 9, arranged one inside the other, and of increasing sizes from the internal pocket 7 to the external pocket 9.

Each pocket 7, 8 or 9 is made up of two assembled flanks connected by lines of piqflre 10 and forming a sleeve 11 in which the end 4 is fitted.

Thus, the pressurized fluid exiting from the orifice 5 is caused to pass through the porous pockets 7, 8 and 9 (arrows 12 in FIG. 3) which oppose resistance to it. This results in expansion of the fluid and the elimination of any noise at the outlet of the end 4 of the pipe 2, as has been explained above.

Claims (6)

1- Ventilation system comprising a duct (2) provided with at least one exhaust port (5) and connected to a source of pressurized fluid (3), characterized in that said exhaust port (5) of said pipe (2) opens into at least one closed pocket (7, 8, 9) made of a porous flexible material, the porosity of which is such that an overpressure of the fluid appears in said pocket, the latter having a diffusion surface fluid large enough for the fluid passing through it to relax with an acceptable sound level. 2- System according to claim 1, characterized in that the pocket (s) t7, 8, 9) are made of canvas or the like. 3- System according to one of claims 1 or 2, characterized in that it comprises several pockets (7, 8, 9) nested one inside the other. 4- System according to claim 3, characterized in that the porous wall surface of the pockets (7, 8, 9) increases from the inner pocket (7) towards the outer pocket (9). 5- System according to one of claims 1 to 4, characterized in that each pocket comprises a sleeve (11) in which is fitted said end (4) of the pipe (2). 6- Protective tracksuit provided with an internal ventilation system comprising a pipe (2), provided with an exhaust orifice (5) opening inside said tracksuit (1) and connected to a source of fluid (3 ) under pressure1 characterized in that said ventilation system is of the type specified under any one of claims 1 to 5.