FR2686299A1 - Aeraulic device for improving the hydrothermic comfort of vehicle seats - Google Patents

Abstract

The invention relates to a ventilation system built into the mass of the seat and in the form of a network of surface ducts inside which there circulates a flow of air, the role of which is to evaporate perspiration from the body at the points of contact, this perspiration being particularly abundant under certain climatic conditions. The ducts are recesses (1) provided in the mass of the seat (2) emerging on its surface, the orifices being distributed inside points of contact with the body. Forced (pulsed) air circulating inside these recesses evaporates the perspiration diffusing into the covering (4) of the seat. The flow rate of air is preferably forced by a fan into the aeraulic network thus constituted. After it has passed through the network and has fulfilled its drying function, the air is discharged into the passenger compartment, where the general ventilation system takes charge of evacuating it. The device according to the invention relates to the constructors of vehicles, as well as equipment manufacturers tasked with manufacturing seats.

Description

 The present invention relates to an aeraulic device for improving the hygrothermal comfort of the seats of various vehicles.

 In this text, the seat will be described as comprising two main elements: the seat, and the backrest, denoted respectively "a" and "d" in FIG. 1.

 The thermal comfort of an individual in an enclosure depends on the balance of the thermal exchanges which develop between his body, dressed or not, and the enclosed environment of this enclosure. One of these modes of exchange is perspiration, whether it is sensitive or insensitive. The heat exchanges take place on all the surfaces of the body.

When the individual is installed on a seat, the amount of heat exchanged by the surfaces of his body in contact with the various parts of the seat, seat and backrest, decreases considerably. The contact of the seat practically neutralizes the convective and radiative exchanges, only authorizing conductive exchange. This, in turn, is almost annihilated by the thermal characteristics of the materials constituting the seat: low thermal conductivity and limited thermal capacity. At first, the body will try to evacuate this heat by the surfaces which are not in contact with the seat, by simple balancing reflex. But it may be, for various reasons, such as a warm thermal atmosphere or a very protective clothing, that this excess cannot be completely transferred to the other regions of the body. The quasi-blocking of the evacuation of the heat in the back, under the thighs and the buttocks then results in a classic physical phenomenon of temperature increase in front of the thermal barrier of the seat, at the interface between it and the body. As the body is constantly self-regulating, its information system will record the increase in temperature, that is to say the sensation of heat, and will seek to combat it using the only mode of exchange. that remains available to him: perspiration. This can be particularly abundant and therefore uncomfortable in summer, when the users of a vehicle such as a passenger car travels under the sun.

 The device according to the invention makes it possible to largely remedy this drawback. The different climatic situations encountered in vehicles show that perspiration is practically inevitable, in the absence of a cooling system for the air in the passenger compartment ventilation. It is a question here of evacuating it and therefore of making it insensitive, rather than deleting it.

 Our device is in the form of a ventilation system integrated into the seat, that is to say a network of pipes partially ventilating the zones Z1 and Z2 of the seat and the backrest (fig 3) by flush of these pipes. These zones Z1 and Z2 correspond to the contact surfaces of the body with the seat. The zone Z1 is that of the contact of the lower thighs and the buttocks with the seat of the seat. The zone Z2 is that of the contact of the back of the body with the backrest. These areas can be defined using a standard subject commonly used in seat design. In the mass of the material constituting the seat and the seat back (2) and (9), FIGS. 4 and 7, recesses are made allowing the flow of air, forced or not, under the covering covering. (4) and (10).

These recesses open onto the surface of the seat via orifices (6) and (12) as shown in FIGS. 4, 5, 6, and 7 and are distributed inside an area having the outline of the lines (5) and (7) delimiting the contact of the body with the seat. The pulsed flow of air in these recesses takes place parallel to the contact surface, thus improving the hygrothermal exchanges. This device allows the contact areas, back, under the thighs and buttocks to find a convective exchange whose vocation is
I evaporation of perspiration. This will diffuse through the seat covering covering (two-phase impregnation) and will be entrained by the forced convective air current circulating in the recesses.

This air is preferably taken from outside the passenger compartment, from the enclosure inside which the individual is located. It is optionally treated, depending on the external climatic conditions. The material, or the set of materials constituting the seat (2) and (9) must, under the pressure of the body, prevent the closing of the lips of the separating parts of the recesses (3) and (11), leaving the orifices (6) and (12) a size allowing the air flow to operate its drying function. Likewise, the deformations of the mass of the seat (2) and of the backrest (9) should not cause the closing constriction of the recesses (1) and (8).

The covering coating (4) and (10) may have a less tight mesh on the zones Z1 and Z2 delimited by the contour lines (5) and (7), thus having greater air permeability.

 According to the particular embodiments - the recesses (1) and (8) may have transverse and longitudinal geometries different from those presented in FIGS. 4, 5, 6 and 7, from which various shapes of orifices (6) may arise and (12). An example of different transverse geometry is given in Figure 9.

- the recesses can be distributed, inside zones Z1 and Z2, in a different manner from that presented in FIGS. 4, 5, 6, and 7.

- the orifices (6) and (12) corresponding to the recesses (1) and (8) may not be continuous.

- the number of recesses (1) and (8) may be different from that presented in Figures 4, 5, 6 and 7.

- the distribution of the recesses (1) and (8) may be different from that presented in FIGS. 4, 5, 6 and 7.

- The nature of the material constituting the mass of the seat (2) and (9) can be arbitrary and is not linked to the device of the present invention.

- The shape of the material constituting the mass of the seat (2) and (9) can be any and is not related to the device of the present invention.

- The nature of the covering coating (4) and (10) can be arbitrary and is not linked to the device of the present invention.

- The presence of the covering coating (4) and (10) is not linked to the device of the present invention: it can possibly be omitted.

Figure 1 shows a profile view of the seat, with the names of its two main parts, seat and back. This graphic description of the seat is indicative and does not prejudge the type of seat to which the device of the present invention can be applied. These observations extend to all of the figures.

Figure 2 shows a front view of the seat.

FIG. 3 represents a perspective view of the seat, with the designation of the zones Z1 and Z2 of contact with the human body: below the thighs, buttocks and back.

Figure 4 shows the section AA of the seat, with the recesses allowing the circulation of air.

FIG. 5 represents a top view of the seat, showing an example of the distribution of the orifices of the recesses, inside the zone Z1 of contact of the thighs and the buttocks with the seat.

FIG. 6 represents a front view of the backrest, showing an example of the distribution of the orifices of the recesses, inside the zone
Z2 of back contact with the seat.

FIG. 7 represents the section BB of the seat back, with the recesses allowing the circulation of air to be highlighted.

FIG. 8 represents the section CC of the seat. This section describes an example of installation of the device, connected to a supply network of forced air.

 With reference to these drawings, the device consists in the creation of an internal air network at the seat, constituted by the recesses (1) and (8), formed in the mass of the seat (2) and the backrest (9) from the headquarters. Air is brought to these recesses by blowing. As an indication, the connection network described in FIG. 8 shows how the distribution of air flows can be organized. The air enters (13) through a flexible connection junction to the supply network, thus allowing the possible displacement of the seat during its adjustment. This air flow may have been processed before entering the device. However, it should be noted that heating in winter or cooling in summer of this air flow is not desirable: in winter, the seat plays a role of sufficient thermal protection, and in summer, a supply of fresh air. on contact areas is not recommended. The air flow circulates in the duct (14) and feeds the duct (15) for distributing the air in the recesses (1). The air then circulates in the recesses (1), the orifices (6) of which are blocked by the presence of the individual on the seat. These flows are recovered in the collecting duct (16) which in turn supplies the intermediate ducts (17) (18) (19). The conduit (18) is a flexible conduit allowing the backrest to move relative to the seat. The duct (20) in turn distributes the flows in the recesses (8) of the backrest. Finally, the collector (21) collects the flows which pass into the passenger compartment through the conduit (22).

The air circulating in the recesses evaporates the perspiration diffusing in the covering of covering (4) and (10), or, in the absence of this covering, directly that of the garment of (individual. The flow of air brought towards the seat seat can, as in the previous example, after passing through the recesses, be taken up and directed towards the recesses in the backrest.

The air flows circulating in the seat and in the backrest can be independent. Finally, after passing through the recesses and having completed its drying function, the air is discharged directly into the passenger compartment where a general ventilation will take care of the training.

When the individual settles in the seat, the masses of the seat (2) and the backrest (9) can deform, but these deformations remain such that the separating parts of the recesses (3) and (11) do not block not the orifices (6) and (12), and / or do not cause the closing constriction of the recesses.

The device according to the invention is particularly directed towards all vehicle manufacturers where seated, drivers, pilots and passengers are seated. The equipment manufacturers responsible for manufacturing the seats are also concerned.

Claims (7)

1) Aeraulic device allowing the improvement of the hygrothermal comfort of the seats of various vehicles characterized in that it comprises a network of recesses (1) and (8) playing the role of flush pipes on the surface of the seat and the seat back, open on it by orifices (6) and (12), arranged inside the contours (5) and (7) delimiting the zones Z1 and Z2 of contact with the human body, below the thighs, buttocks and back with the seat, recesses inside which circulates an air flow, in forced movement, flowing in parallel to the contact surface and largely evaporating the perspiration secreted on the said contact areas. 2) Device according to claim 1 characterized in that I 'air supply to the device is made by I' air taken from I 'outside of the passenger compartment in which the seat is located. 3) Device according to claim 1 characterized in that I 'air supply to the device can be made by I' air taken from inside the cabin in which is the seat. 4) Device according to any of the preceding claims, characterized in that the recesses (I) and (8) may have varied transverse and longitudinal geometries. 5) Device according to any of the preceding claims characterized in that the orifices (6) and (12) of the recesses (1) and (8) may have various geometries. 6) Device according to any of the preceding claims, characterized in that the number of recesses can be reduced to the number of five or three for the seat and to four or two for the backrest. 7) Device according to any of the preceding claims characterized in that the orifices (6) and (12) corresponding to the recesses (1) and (8) may not be continuous.