EP0638775A1 - Process and device for the cross-section control of an air inlet opening in a room - Google Patents

Abstract

This process consists of making the opening cross-section (2) subject to, on the one hand and mainly, the difference between the quantity of water vapour contained in the air of the room (Vi) and the quantity of water vapour in the outside air (Ve), so that the opening cross-section increases when this difference increases, and, on the other hand, in an independent manner, to the quantity of water vapour in the outside air. Application to the ventilation of rooms. <IMAGE>

Description

The different rooms of a dwelling have variable ventilation needs in relation to each other, and also, for the same room, over time. This need evolves mainly according to the type of rooms and the occupation. With regard to technical parts, the need for ventilation depends mainly on the emission of water vapor. Regarding the main rooms, bedrooms and living room, it is the number of people occupying these rooms that determines the level of ventilation required.

Currently, the most advanced technique in terms of managing the ventilation requirement, allows the opening section of the air inlets and air outlets to be controlled by the relative humidity of the ventilated rooms. For the air outlets, the measurement of the relative humidity alone is sufficient, since the temperature of the rooms in a dwelling varies very little and the water vapor emissions in the technical rooms where these outlets are placed air are generally quite strong.

The production of water vapor in the bedrooms and living rooms, which are the rooms affected by the air inlets, is mainly due to the breathing of the occupants. This production of water vapor is estimated between 40 and 80 grams of water per hour and per person depending on the metabolism and ambient conditions.

Rooms equipped with furniture, in particular curtains, rugs, carpets, exhibit a "buffer" behavior which attenuates the variations in humidity which one should find if one considered only the emission of water vapor. .

The low water vapor emissions associated with the "buffering" behavior of the furniture means detecting small variations in humidity in the air. Studies have shown that the variation in relative humidity in a room occupied by two people and an empty room with standard furniture is of the order of 10 to 15%, regardless of the season, as long as ventilation is carried out according to the regulations in force in France since 1982.

It should be considered that the function of the air inlets is not only to allow an air intake, but also to distribute it as well as possible to ventilate mainly the occupied rooms. It is therefore essential to detect small variations between an occupied room and an empty room, in order to correctly distribute the total extracted flow. this is all the more true that one works in mechanical extraction only, the enslavement in the technical parts being able to lead to a reduction of the total flow extracted, which it is imperative to distribute in the occupied parts, under penalty of degrading the quality air in these rooms.

• 4 grammes d'eau par kg d'air conduisent à 30 % d'humidité relative à 20°C,
• 6 grammes d'eau par kg d'air conduisent à 40 % d'humidité relative à 20°C,
• 8 grammes d'eau par kg d'air conduisent à 55 % d'humidité relative à 20°C,
• 10 grammes d'eau par kg d'air conduisent à 70 % d'humidité relative à 20°C.

In addition, the quantity of water vapor contained in the outside air is very variable according to the season. For example, there are about 4 grams per kg of air in January and 10 grams per kg of air in August in Paris. When the outside air is brought back to the temperature of a living room, which is roughly fixed throughout the year, the resulting relative humidity can vary significantly. This is how for an empty room:

• 4 grams of water per kg of air lead to 30% relative humidity at 20 ° C,
• 6 grams of water per kg of air lead to 40% relative humidity at 20 ° C,
• 8 grams of water per kg of air lead to 55% relative humidity at 20 ° C,
• 10 grams of water per kg of air lead to 70% relative humidity at 20 ° C.

The object of the invention is to provide a method and a device for adjusting the opening section of a ventilation air inlet in a room, which takes account of the humidity of the outside air and of the air humidity inside the room, which also depends on the presence or not of occupants in a room, to modulate the opening section of the air inlet.

For this purpose, the process which it relates to, consists in slaving the opening section, on the one hand and mainly, unlike the amount of water vapor contained in the air of the room and the amount of water vapor from the outside air, so that the opening section increases when this difference increases and, on the other hand, independently, to the amount of water vapor in the outside air.

This solution makes it possible to take into account both the amount of water contained in the outside air and the amount of water contained in the room air.

According to one characteristic, this method consists in measuring the relative humidities contained respectively in the air of the room and in the outside air, at temperatures as close as possible to each other and largely independent of the outside temperature.

It is important, for the comparison between the two relative humidities respectively in the air of the room and in the outside air to be consistent, that the temperatures are as close as possible to each other, since a difference of 1 ° C in a temperature range around 20 ° C results in an error of 3% relative humidity for a given quantity of water in the air.

In order to ensure independence of the response with respect to the outside temperature, it is also important that the relative humidities are read at temperatures as close as possible to the inside temperature, the fluctuations of which are much smaller.

According to a first embodiment, the opening section of the air inlet is always the same for a given difference in humidity, whatever the external climatic data. The section of the opening increases only when the difference in the quantities of water vapor increases. This law of variation of the opening section leads to an identical base opening in summer and in winter, that is to say to an identical section when the quantity of water vapor in the outside air varies.

According to another embodiment, this process consists in slaving the opening section, on the one hand, to the difference of the amount of water vapor contained in the air of the room and the amount of steam d water from the outside air, and, on the other hand, the amount of water vapor from the outside air.

In this case, it is a question of taking into account not only the difference between the quantities of water vapor contained in the local air and in the outdoor air respectively, but also the quantity of water vapor of outside air.

In this case, the section of the base opening will vary depending on the amount of water vapor in the outside air, even if the difference between the amounts of water vapor contained in the room air and in the outside air is zero.

According to a first possibility, this method consists in increasing the section of the opening when the quantity of water vapor in the outside air increases.

This mode of implementation leads to a larger base opening in summer than in winter, since, as indicated above, the quantity of water vapor in the outside air is greater in summer than the 'winter.

According to another embodiment, this method consists in reducing the section of the opening when the quantity of water vapor in the outside air increases.

In this case, the basic opening is smaller in summer than in winter, since the cross-section of the inlet opening decreases when the amount of water vapor in the outside air increases. This latter mode of implementation may be advantageous in the case where the quantity of water vapor in the outside air is very large, and where it is desired to isolate the room from the outside air when the outside humidity increases. and that the room is not occupied.

A device for implementing this method comprises two chambers in communication respectively with the outside air and with the air inside the room. In order to ensure a stable temperature and close to the interior temperature, the enclosures can be located in the room to be ventilated, and designed in such a way that the heat inputs from the walls are much greater than those from the air.

It is also possible to preheat the fresh air to a temperature close to the interior temperature, if the previous arrangement is insufficient. The chambers are separated from each other by a water vapor tight heat exchanger ensuring final balancing of their respective temperatures, the two chambers containing two bundles of fibers sensitive to relative humidity and kept in tension by a spring, and being connected by a drive mechanism to at least one adjustment flap of the section of the air inlet opening, the drive mechanism of the adjustment flap (s) being controlled, on the one hand, by the relative movement of the two beams and, on the other hand, by their overall movement.

According to one embodiment, one end of each bundle is fixed, while its other end is mounted, outside the enclosure containing the bundle of fibers in question, on a part in the form of a beam which, resting on an axis disposed at the end of the exchanger and vis-à-vis which it can pivot, is connected directly or indirectly to at least one shutter for adjusting the section of the air inlet opening.

The two bundles of fibers, for example textile fibers, have the ability to lengthen when the humidity increases and to shorten when the humidity decreases. When the difference in humidity is balanced between the inside and the outside, and the humidity varies in the same way inside the room as outside, the two beams lengthen or shorten by the same value. On the contrary if, when the room is occupied by people, the humidity increases inside the room, the bundle of fibers subjected to the influence of the air inside the room becomes longer than the other beam, causing an inclination of the beam, which is used to adjust the section of the air inlet opening in the room.

According to a first embodiment, on the flail-shaped part is fixed the end of at least one cable, the other end of which is fixed to a flap mounted in the air inlet opening.

Insofar as it is desired to adjust the section of the air passage opening taking into account, on the one hand, the difference in humidity between the interior of the room and the exterior, and, d on the other hand, from the external humidity, the ends of two cables are fixed respectively on the flail-shaped part and on the support thereof, the other ends of which are fixed on two flaps mounted in the inlet opening air, articulated around the same axis in order to be able, in one position, to be pressed against each other, one of the flaps being full, and the other comprising at least one central opening capable of being more or less closed by the first part.

When the quantity of water vapor contained in the air is the same in the room and outside of it, the two flaps are pressed against each other, and the basic opening is delimited between these two flaps and the inner wall of the conduit. When the amount of water vapor inside the room becomes greater than the amount of steam of water from the outside air, the full flap switches relative to the perforated flap, thus opening an additional passage inside this second flap to increase the air passage section.

According to another embodiment of this device, the flail-shaped part is secured to a lever acting on a mixing valve with two different air pressures, the pressure of the mixture being collected inside a pocket deformable acting on a flap mounted in the air inlet opening.

Advantageously, the pressures inside and outside the room are different, and are used to supply the mixing valve.

According to one possibility, the mixing valve comprises a piston on one end of which bears the lever fixed on the workpiece in the form of a beam, the piston comprising a transverse opening for carrying out the adjustable communication, according to its axial position, of two enclosures to different pressures with an enclosure at the mixing pressure.

• Figures 1 et 2 sont deux vues d'un premier dispositif dans deux conditions de fonctionnement ;
• Figure 3 est une vue schématique d'un second dispositif ;
• Figure 4 est une vue en perspective d'un troisième dispositif ;
• Figure 5 est une vue en coupe du dispositif de figure 4 ;
• Figure 6 est une vue d'un diagramme de fonctionnement d'une ouverture d'entrée d'air équipée du dispositif selon l'invention.

In any case, the invention will be clearly understood with the aid of the description which follows, with reference to the appended schematic drawing showing, by way of nonlimiting examples, three embodiments of this device:

• Figures 1 and 2 are two views of a first device in two operating conditions;
• Figure 3 is a schematic view of a second device;
• Figure 4 is a perspective view of a third device;
• Figure 5 is a sectional view of the device of Figure 4;
• Figure 6 is a view of an operating diagram of an air inlet opening equipped with the device according to the invention.

FIG. 1 represents a first device, in which the air inlet opening in a room is designated by the reference 2. This device comprises two enclosures Vi and Ve, of which that Vi is connected by a conduit 3 with the inside the room to be ventilated, and of which that Ve is connected by a conduit 4 outside the room. These two enclosures Vi and Ve are parallel, and separated from each other by a heat exchanger 5 so that the temperatures in the two enclosures are as close as possible to each other. This heat exchanger 5 is mounted sliding through the support 6 located near one of the ends of the speakers, and kept pushed towards the other end of the speakers, which it also crosses, by a spring 7.

Inside the two enclosures Vi and Ve, two bundles Fi and Fe of textile fibers, sensitive to humidity, are mounted. These two parallel beams are fixed at their end located on the side of the wall 6, and mounted at their other end, after crossing the front wall of the corresponding enclosures, on a part 8 in the form of a beam which is supported on an axis located in end of the heat exchanger 5, with the possibility of pivoting about this axis. The two bundles Fi and Fe are held in tension by a spring 10. On the support of the beam 8 and on the beam 8 are fixed respectively the ends of two cables 12 and 13, the other ends of which are fixed, after passing over pulleys 14, on two flaps 15 and 16 respectively. The flap 15 is articulated around an axis 17 transverse to the axis of the opening 2, and has a central opening 18. The flap 16 is articulated around the same axis 17, and is capable of pivoting with respect to the flap 15 to come either to press against it, or to form an angle with the latter and more or less clear the central opening 18. The flap 15 defines the base opening designated by the reference 19 while the flap 16, in combination with the opening 18 of the flap 15, defines the complementary air passage section, when there is a difference between the quantities of water vapor contained in the air inside the room and in the outside air erior.

As long as the air quantities respectively inside the room and outside are equal, the beams Fi and Fe have the same length, as shown in Figure 2, the only possible movement being a translation parallel to the heat exchanger 5, during a variation in humidity, of the same value for the outside air and for the indoor air. The base opening 19 then varies as a function of this variation in humidity. If, on the contrary, the quantity of water vapor inside the room increases, that is to say that there is a difference with the quantity of water vapor in the outside air, the beam Fi elongates more than beam Fe, which results, as shown in FIG. 1, by an imbalance and a rotation of the beam 8 around the axis 9. This rotation is materialized by a pivoting of the flap 16, which gives off more or less the opening 18 of the flap 15, thereby creating an additional air passage relative to the base opening 19. When the quantity of water vapor contained in the room decreases, the beam Fi retracts, and its length becomes again equal to that of the beam Fe, which results in a relative pivoting movement of the flap 16 with respect to the flap 15, until it comes to bear one against this flap 15, when it there is no longer any difference between the quantities of water vapor in the room and outside respectively.

FIG. 3 represents another device, in which the same elements are designated by the same references as above.

The operation of the fiber bundles Fi and Fe is the same as in the previous case, with pivoting of the beam 8 when there is an imbalance between the quantities of water vapor inside the room and outside. This second device aims to ensure a different processing of the information received by the flail 8. For this purpose, the flail is secured to a lever 22, the free end of which bears against the head of a piston 23 mounted to slide inside a cylinder 24, and which is subjected to the action of a spring 25 holding this piston head pressed against the lever 22. In one wall of the cylinder 24 are formed two orifices 26 and 27 parallel to it one to the other, and in the opposite wall two corresponding orifices 28 and 29 respectively opening into a mixing chamber 30. In this device, an air duct 32 is used, in which a positive pressure prevails with respect to the room to be ventilated, of the order of 10 to 40 Pa. There is a pressure P + in the upstream part of the air supply duct, and a pressure P- downstream thereof, which can be either the pressure of the room to be ventilated, or a negative pressure obtained through d 'A Venturi effect device, placed between the duct 32 and the room to be ventilated. The orifices 26 and 27 of the cylinder 24 are supplied respectively by the pressure P + and the pressure P-. A transverse opening 33 is formed in the piston 23, to allow the passage of air respectively from the orifices 26 and 27 towards the mixing chamber 30. It goes without saying that depending on the position of the opening 33 of the piston 23, the mixture pressures P + and P- are not done in the same proportions, which influences the value of the mixing pressure Pm in the mixing chamber 30. This mixing pressure also depends of the geometry of the cylinder and of the passage sections of the orifices 26 and 27.

The mixing pressure Pm is injected into a flexible bag 34, located in a volume 35 in communication with the room to be ventilated. When it is the pressure P + which is injected into the pocket 34, the latter is inflated, and the flap 36 closes the air supply duct 32. If, on the contrary, the pressure P- is injected into the pocket flexible 34, the flap 36 is pushed back by the pressure P + prevailing upstream of the conduit 32, providing a complete opening of this flap. The injection of an intermediate mixing pressure Pm makes it possible to position the flap 36 so as to obtain the desired section adapted to the difference in humidity between the air inside the room and the air outside of it.

When the two beams Fi and Fe elongate or retract simultaneously, the translational movement of the lever 22 is communicated directly to the piston 23 without amplification phenomenon. On the contrary, when there is a differential elongation of the two beams Fi and Fe, the rotational movement of the beam 8 causes an amplification of the translational movement of the piston 23.

Figures 4 and 5 show a third device in which the same elements are designated by the same references as above.

In this case, the two fiber bundles Fe and Fi are arranged parallel to one another in two enclosures Ve and Vi in communication with the outside air and the inside air respectively. These two enclosures are separated by a sealed wall 5, however allowing heat exchanges, so that the temperatures in these two enclosures are as close as possible. The two bundles Fe and Fi are substantially parallel to the opening of a duct 38, the opening of which can be more or less closed by a flap 46. Each of the two bundles of fibers is fixed, at one of its ends, at a fixed point 39a, 39b. At its other end, subjected to the action of a spring respectively 40, 42, each beam Fe, Fi is mounted on a part 43, 44. The two parts 43, 44 are pivotally mounted around an axis A, common to the two parts, perpendicular to the two bundles of fibers Fe, Fi, and parallel to the plane of the opening of the conduit 38.

The part 43 for fixing the beam Fe, located in the enclosure Ve in communication with the outside air, also carries an axis B of articulation of the flap 46, substantially parallel to the bundle of fibers Fe, Fi. For its part, the part 44 for fixing the beam Fi carries the end of a lever 47, the other end of which is mounted on the external face of the flap 46. When the quantities of water vapor in the air at the interior of the part and the exterior thereof are equal, the beams Fi and Fe have the same length, and the only possible movement for the flap 26 is a pivoting around the axis A. The more the beams Fe, Fi lengthen, the more the flap 46 opens and releases a large passage section.

When the amount of water vapor inside is greater than the amount of water vapor outside, which is the case when a room is occupied by people, the beam Fi becomes longer that the beam Fe, the part 44 pivots more than the part 43, and drives the shutter in rotation around the axis B, which further increases the cross section of the air. It is possible to obtain a suitable adjustment of the device taking into account the distance between the end of the lever 47 associated with the flap 46 and the axis A, as well as between the distance between this same end and the axis B.

When the quantity of water vapor inside decreases, the lever 47 pushes the shutter by rotation of the latter around the axis B and makes it possible to reduce the passage section.

A return spring 48 of the flap 46 in the closed position makes it possible to maintain a minimum opening by compensating for the pressure in the air supply duct. Similarly, it is possible to compensate for the weight of the shutter when the entry is placed in a horizontal position, for example in a ceiling.

FIG. 6 represents a diagram of operation of an air inlet opening equipped with the device according to the invention. In this diagram, the abscissa axis indicates the quantity of water vapor H, while the ordinate axis indicates the value of the opening O of the air inlet. This opening can vary between a minimum opening Om and a maximum opening OM. The solid line curve indicates the overall movement, i.e. when the amount of water vapor inside the room is equal to the amount of water vapor outside, which corresponds to a rotation around axis A in the last device described. The dashed lines indicate the possibility of complementary opening of the shutter, by rotation of the latter around the axis B in the last device described, when the quantity of water vapor inside the room is greater than the amount of water vapor in the outside air.

As is apparent from the above, the invention brings a great improvement to the existing technique by providing a device of simple design making it possible to ensure the ventilation of a room taking into account the occupation thereof, by playing on the difference between the amount of water vapor in the air inside the room, and the water vapor contained in the outside air.

As it goes without saying, the invention is not limited to the sole embodiments of this device, described above by way of examples, on the contrary it embraces all variants.

Thus, in particular, the means for detecting the quantity of water vapor inside and outside the room could be different and not consist of beams, the variation in length of which is used. , but by hygrometers of another type, or even that the heat exchanger between the two humidity measuring chambers could be different without departing from the scope of the invention.

Claims (13)

Method for adjusting the opening section of an air inlet in a room, characterized in that it consists in controlling the opening section (2), on the one hand and mainly, unlike the quantity of water vapor contained in the room air (Vi) and quantity of water vapor of the outside air (Ve), so that the opening section increases when this difference increases and, d ' on the other hand, independently, the amount of water vapor in the outside air. Adjustment method according to claim 1, characterized in that it consists in measuring the relative humidities contained respectively in the local air and in the outdoor air, at temperatures as close as possible to each other and largely independent of the outside temperature. Method according to claim 1, characterized in that it consists in increasing the cross-section of the opening (2) when the quantity of water vapor in the outside air increases. Method according to claim 1, characterized in that it consists in reducing the cross-section of the opening when the quantity of water vapor in the outside air increases. Device for implementing the method according to any one of Claims 1 to 4, characterized in that it comprises two chambers (Ve, Vi) in communication with the outside air and with the air inside, respectively of the room, designed in such a way that the heat exchanges are much greater by the walls than by the air, separated from each other by a heat exchanger (5) sealed against water vapor ensuring a balancing of their respective temperatures, the two enclosures containing two bundles of moisture-sensitive fibers (Fe, Fi) and held in tension by a spring, and being connected by a drive mechanism to at least one shutter for adjusting the cross-section of the air inlet opening in the room, the drive mechanism being controlled, on the one hand, by the relative movement of the two beams and, on the other hand, by their overall movement. Device according to claim 5, characterized in that one end of each beam (Fe, Fi) is fixed, while its other end is mounted, outside the enclosure containing the beam of fibers considered, on a part (8) in the form of a beam which, bearing on an axis (9) disposed at the end of the exchanger and vis-à-vis which it can pivot, is connected directly or indirectly to at least one adjustment flap (15, 16, 36) of the section of the air inlet opening (2, 32). Device according to Claim 6, characterized in that the end of at least one cable (12, 13) is fixed to the flail-shaped part (8), the other end of which is fixed to a flap (16 , 15) mounted in the air inlet opening (2). Device according to all of claims 3 and 6, characterized in that, on the part (8) in the form of a beam and on the support thereof, the ends of two cables (12, 13) are fixed respectively, the others of which ends are fixed on two flaps (15, 16) mounted in the air inlet opening (2), articulated around the same axis (17) so that they can be pressed one against the other in one position another, one (16) of the flaps being full, and the other (15) comprising at least one central opening (18) capable of being more or less closed by the first flap (16). Device according to claim 6, characterized in that the flail-shaped part (8) is integral with a lever (22) acting on a mixing valve (23, 24) of two different air pressures, the pressure of the mixture being collected inside a deformable pocket (34) acting on a flap (36) mounted in the air inlet opening (32). Device according to claim 9, characterized in that the pressures inside and outside the room are different, and are used for supplying the mixing valve (23, 24). Device according to claim 9, characterized in that the mixing valve comprises a piston (23) on one end of which bears the lever (22) fixed on the workpiece (8) in the form of a beam, the piston (23) having an opening transverse (33) for carrying out the adjustable communication according to its axial position, of two chambers (26, 27) at different pressures (P +, P-) with a chamber (30) at the mixing pressure (Pm). Device according to claim 6, characterized in that each bundle of moisture-sensitive fibers (Fe, Fi) is fixed at one of its ends to a fixed point and at its other end, subjected to the action of a spring (40, 42) on a part (43, 44) pivotally mounted around a axis (A), this axis being common to the two parts, perpendicular to the two fiber bundles and parallel to the plane of the air intake opening, the beam fixing part (43) located in the enclosure (Ve) in communication with the outside air also carrying an axis (B) of articulation of the flap (46) for adjusting the passage section of the air inlet, this axis (B) being substantially parallel to the fiber bundles (Fe, Fi), while the part (44) for fixing the bundle (Fi) located in the enclosure (Vi) carries the end of a lever (47) the other end of which is mounted on the outer face of the flap (46). Device according to claim 12, characterized in that the shutter (46) is equipped with a return spring (48) making it possible to maintain a minimum opening by compensating for the pressure in the air supply duct.

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