FR3032923A1 - THERMAL DEVICE FOR SEAT OF MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a seat element for a motor vehicle, provided with at least one thermal device (2) comprising: at least one coil of Peltier elements (26) electrically connected in series by first sections (22) on the cap ( 32) and second sections (28) side padding (34), and conductive pellets (4) of thermal diffusion associated with all or part of the first sections, each pad being in contact with only one first section.

Description

B13892 - 3776 1.EN 1 THERMAL DEVICE FOR A MOTOR VEHICLE SEAT Field This description relates generally to motor vehicle seats and, more particularly, to the thermal devices (heating or cooling) fitted to such seats. The present description relates more particularly to the thermal layers interposed between the quilting and the cap of a seat element lining. DISCUSSION OF THE PRIOR ART Motor vehicle seat cushions are more and more often equipped with thermal elements intended to improve the comfort of the occupant. A large number of heating and cooling systems based on different principles (heating resistors, Peltier elements, fans, heat transfer fluids, etc.) are sometimes known to be combined. Systems based on Peltier (effect) elements have the advantage of being reversible electrical devices, that is, capable of operating as both a heating element and a cooling element. Of particular interest here are thermal devices whose thermal elements are Peltier elements. 3032923 B13892 - 3776 1.EN 2 Abstract It would be desirable to improve the performance of thermal devices fitted to motor vehicle seats. Thus, one embodiment provides a thermal device for a motor vehicle seat that overcomes all or some of the disadvantages of conventional thermal devices. One embodiment aims at a solution more particularly adapted to Peltier effect type thermal generation elements.

Thus, an embodiment provides a seat element for a motor vehicle, provided with at least one thermal device comprising: at least one coil of Peltier elements electrically connected in series by first sections of the cap and second sections of the side padding; and conductive thermal diffusion pellets associated with all or part of the first sections, each pellet being in contact with only one first section. According to one embodiment, the first sections consist of uninsulated conductive wires. According to one embodiment, the first sections are approximately parallel to the surface of the seat element. According to one embodiment, the pellets are based on copper or aluminum.

According to one embodiment, the pellets are cap-side. According to one embodiment, all pellets have rectangular shapes. or part or part of or part of the pellet is in accordance with one embodiment, all pellets have diamond shapes. According to one embodiment, any pellets have complementary shapes. According to one embodiment, each mechanical contact with a first section.

3032923 B13892 - 3776 1.EN 3 An embodiment also provides a seat for a motor vehicle comprising at least one seat element. BRIEF DESCRIPTION OF THE DRAWINGS These and other features and advantages will be set forth in detail in the following non-limiting description of particular embodiments in connection with the accompanying figures in which: FIG. 1 is a diagrammatic representation; in perspective of an embodiment of a motor vehicle seat; Figure 2 is a schematic representation of a Peltier thermal device; Figure 3 is a schematic and partial section of an embodiment of a thermal device; Figure 4 is a schematic and partial elevation of an embodiment of a thermal device; Figure 5 is a schematic and partial elevation of another embodiment of a thermal device; and FIG. 6 partially illustrates a detail of an alternative embodiment of a thermal device. Detailed Description For the sake of clarity, only the elements useful for understanding the embodiments that will be described have been shown and will be detailed. In particular, the embodiment of the seat elements (frame, padding and cap) has not been detailed, the described embodiments being compatible with the usual embodiments of seat elements equipped with thermal elements. In addition, the devices for connecting the thermal elements to one or more energy sources or control devices have also not been detailed, the embodiments described being, again, compatible with the usual embodiments. It should be noted that, in the figures, the structural and / or functional elements common to the various embodiments may have the same references and may have identical structural, dimensional and material properties. In the following description, when reference is made to absolute position qualifiers, such as the terms "forward", "backward", "up", "down", "left", "right", etc. , or relative, such as the terms "above", "below", "upper", "lower", etc., or with qualifiers for orientation, such as the terms "horizontal", "vertical", etc., reference is made to the orientation of the figures or to a seat 10 in a normal position of use. Unless otherwise specified, the terms "approximately", "substantially", and "of the order of" mean within 10%, preferably within 5%. Figure 1 is a schematic perspective view of an embodiment of a seat 1 equipped with thermal devices.

A seat is generally made of a seat 12 on which is articulated a backrest 14, usually surmounted by a headrest not shown. The linings of the seat elements 12 and 14 (seat and back in this example) are each equipped with a thermal device 2 consisting of a set of thermal generation elements Peltier effect electrically connected in series, by sections, to a source of electrical energy 3. The first conductive sections 22 act as heat sinks. The techniques for producing heating plies from Peltier elements are well known. In the embodiments targeted by the present description, a multi-stranded cable formed of electrically conductive and non-insulated metal wires, most often based on copper or aluminum alloy, is arranged to alternate first diffusion sections 22 or 30 restitution (heating or cooling) in the upper part of the thermal device (cap) and second sections (not visible in Figure 1) capture, capturing or removing heat padding side. At the interfaces 24 between the first diffusion sections and the second collection or discharge sections, the ends of the sections are electrically connected to active parts of Peltier elements (not visible in FIG. figure 1). Depending on the direction of the current in the cable, the first sections 22 (diffusion) are heated or cooled and, conversely, the second sections capture the heat or evacuate. The structure of such a cable is in itself known. In practice, the first sections 22 are approximately horizontal (in the orientation of the figures) or tangential to the liner being spread under the cap, while the second sections are approximately vertical (in the direction of orientation of the figures) or perpendicular to the plane in which the surface of the lining is inscribed. Figure 2 is a schematic sectional view of a Peltier device. This device alternates active parts 262 'of a first type (in practice into a P-type semiconductor material) and active parts 266' of a second type (in practice into an N-type semiconductor material). ), separated by insulating portions 264 '. Conductive sections 22 'and 28' connect the respective ends (upper and lower) of the active portions 262 'and 266' alternating the high and low connections. Thus, in the upper part, first sections 22 'connect, from left to right in the orientation of the figure, an active portion 266' of the second type to the active portion 262 'of the first type adjacent while in the lower part, second sections 28 'connect an active part 262' of the first type to the active part 266 'of the second adjacent type. Diffusion plates 23 'and 29', electrically isolated, are respectively reported on the upper and lower faces. By applying a voltage across the coil thus produced, the upper face constitutes the hot wall, respectively cold, while the lower face constitutes the cold wall, respectively hot. A difficulty which lies in the realization of the heating plies with Peltier effect heat production elements is that the thermal diffusion is not uniform. Although the cable wires are well spaced apart at the level of the first diffusion or restitution sections, the yield is low. Since the wires of the cable are not generally insulated, placing a thermal diffusion plate on the thermal device would put these first sections 22 in short circuit and annihilate the thermal effect, except to insert an electrical insulator which, the more often, is bad thermal conductor. Figure 3 is a schematic and partial section of an embodiment of a thermal device. The first diffusion sections 22 are formed of 10 son of an electric cable electrically connected (for example, glued or welded) at more or less regular intervals to first (upper) ends of first active parts 262 and second parts. Peltier elements 26. The second collection or discharge sections 28, preferably consisting of sections of the same cable (and thus wires), connect between them second (second) ends of the second (266) and first (262) active parts, staggered relative to the sections 22. Thus, the first end (upper here) of each first active portion 262 is connected, by a first section 22, to a first end (upper) of a second active portion 266 adjacent in a first direction (for example to the left in the orientation of Figure 3) while its second end (here below) is connected, by a second section 28, to a second end (lower) 25 of a second active portion 266 adjacent in the second direction (to the right in the orientation of Figure 3) of the coil formed. This connection is reproduced all along the coil. The first sections 22 are cap-side 32 and the second sections 28 are integrated in the padding 34. In practice, each section 28 forms a loop penetrating into the padding so as to increase the heat-exchange surface. According to the embodiment of FIG. 3, provision is made to associate, at each first section 22, a thermal diffusion chip 4. This pellet is made of a thermally (and electrically) conductive material, for example, copper-based or aluminum-based. The shape and size of each pellet are chosen, according to the pattern provided for the coil formed by the thermal device, so that no pellet touches each other, which would otherwise short-circuit Peltier elements 26. Thus, it is expected to interpose, between the cap 32 and the thermal generation elements, a set of elements 4 or thermal diffusion pellets. These elements 4 are disposed vertically above the device 2 and individually in contact with a first section 22. In practice, the pellets 4 are preferably welded or glued with a conductive adhesive, at least thermally, to the wires of the first Fig. 4 is a schematic front view of an exemplary embodiment of a thermal device of the type described in connection with Fig. 3. According to this embodiment, each diffusion pad 42 is shaped square or rectangular. A first dimension (for example horizontal in the orientation of the figure) of each pellet 42 is smaller than the distance between two Peltier elements 26, neighbors in the series association, or the length of a first section 22. in place on the packing, so as not to cause a short circuit. A second dimension (for example vertical in the orientation of the figure) of each pellet is less than the difference between two first sections 22 in this second dimension. Thus, the pellets do not touch each other. FIG. 5 is a diagrammatic front view of another embodiment of a thermal device of the type described in relation with FIG. 3.

According to this embodiment, each diffusion pad 44 has a diamond shape, one of whose diagonals (for example, horizontal in the orientation of the figure) is approximately parallel to a line connecting two Peltier elements 26, neighbors in the line of FIG. coil. The second diagonal (vertical in the orientation of the figure) is less than the distance between two non-consecutive lines of the coil, separated by a single line. Preferably, the coil of the thermal device is arranged so that the Peltier elements 26 are staggered from one line to another.

Thus, the lozenges constituting the pellets 44 occupy a maximum of space without touching each other. This maximizes the heat exchange surface. The choice of the shapes of the diffusion pellets depends on the path followed by the cable of the thermal device. It will be sought to maximize the heat exchange surface, by providing pellets of complementary shapes, while ensuring electrical insulation between each of the pellets. Figure 6 illustrates an alternative embodiment of thermal diffusion pellets.

According to this example, pellets 46 and 46 'are provided having different shapes from each other but having complementary shapes to maximize diffusion. Depending on the layout of the coil, more than two different shapes can be provided. According to a variant applicable to all the described embodiments, some first sections 22 are not equipped with a diffusion pad, where a thermal diffusion is not necessary. On the other hand, the serpentine lines may have any directions, for example vertical or oblique, and a seat member may include one or more coils. An advantage of the embodiments that have been described is that it is now possible to improve the thermal diffusion in a thermal device consisting of a coil of Peltier elements connected by electrically non-insulated wires.

It will be noted that the cap (fabric, skin, leather, etc.) is generally electrically insulating, whether directly by the nature of the external material or by the presence of a layer of foam a few millimeters thick. (less than 10) which is generally provided in the rear face of the cap.

3032923 B13892 - 3776 1.EN 9 The mounting of the thermal device is not modified with respect to the assembly of a conventional device except that the soldering or bonding of the pellets on the first sections 22, carried out prior to mounting on the liner, avoids the operator 5 to discard the son of the cable, this having been done previously during the fixing of the pellets. Various embodiments have been described. Various variations and modifications will be apparent to those skilled in the art. In particular, the choice of the shape of the conductive pads 10 (square, rectangular, round, oval, polygonal, triangular, etc.) depends on the seat element concerned, the path followed by the thermal device, as well as the necessary adjustments. for other functions in the seat such as, for example, the provision of ventilation or moisture absorption. In addition, 15 different shapes can be combined, provided to respect the insulation between two neighboring pellets. Finally, the practical implementation of the described embodiments is within the abilities of those skilled in the art from the functional indications given above, whether for the choice of constituent materials of thermal diffusion pellets (copper, aluminum, etc.) or constituent materials of Peltier cells.

Claims (10)

REVENDICATIONS1. Motor vehicle seat element (12, 14), provided with at least one thermal device (2) comprising: at least one coil of Peltier elements (26) electrically connected in series by first sections (22); ) cap-like side (32) and second sections (28) side padding (34); and conductive pellets (4; 42; 44; 46,46 ') of thermal diffusion associated with all or part of the first sections, each pellet being in contact with only one first section. 2. Seat element according to claim 1, wherein the first sections (22) consist of uninsulated conductive son. 15 The seat member of claim 1 or 2, wherein the first sections (22) are approximately parallel to the surface of the seat member (12, 14). 4. Seat element according to any one of claims 1 to 3, wherein the pellets (4; 42; 44; 46, 46 ') are based on copper or aluminum. The seat element according to any one of claims 1 to 4, wherein the pads (4; 42; 44; 46,46 ') are cap-like (32). 6. Seat element according to any one of claims 1 to 5, wherein all or some of the pellets (42) have rectangular shapes. The seat member according to any one of claims 1 to 5, wherein all or some of the pellets (44) have diamond shapes. 30 8. Seat element according to any one of claims 1 to 5, wherein all or part of the pellets (46, 46 ') have complementary shapes. 3032923 B13892 - 3776 1.EN 11 The seat member according to any one of claims 1 to 8, wherein each wafer (4; 42; 44; 46,46 ') is in mechanical contact with a first section (22). Motor vehicle seat comprising at least one seat element according to one of claims 1 to 9.