Heating Device For A Seat Heater Of A Motor Vehicle

Abstract

One embodiment of a heating device for a seat heater of a motor vehicle includes a heating device adapted to be placeable between a base body of foam and a seat cover of a vehicle seat. The heating device includes a heating mat having a carrier layer which includes a first surface and a second surface opposite the first surface. The second surface carries a heating conductor for generating heat, and the heating conductor extends over a heating area. The heating device further includes a seat cover upholstery, which can be a foam layer. The second surface of the carrier layer faces the seat cover upholstery, and the first surface of the carrier layer is adapted to face the seat cover and be in direct contact with the seat cover. The heating mat is adapted to be sewable by stitches going through the seat cover, the heating mat, and the seat cover upholstery to form seams extending through the heating area.

Claims

1. A heating device for a seat heater of a motor vehicle, said heating device adapted to be placeable between a base body of foam and a seat cover of a vehicle seat, and said heating device comprising: a heating mat having a carrier layer which comprises a first surface and a second surface opposite said first surface, said second surface carrying a heating conductor for generating heat, and said heating conductor extending over a heating area; and a seat cover upholstery comprising a foam layer; wherein said second surface of said carrier layer faces said seat cover upholstery and said first surface of said carrier layer is adapted to face the seat cover and be in direct contact with the seat cover; and wherein said heating mat is adapted to be sewable by stitches going through the seat cover, said heating mat, and the seat cover upholstery to form seams extending through said heating area.

2. The heating device according to claim 1, wherein said heating conductor is a stranded conductor comprising at least 300 metal filaments.

3. The heating device according to claim 1, wherein said heating conductor is a stranded conductor comprising at least 500 metal filaments.

4. The heating device according to claim 1, wherein said carrier layer of said heating mat consists of felt, fleece, woven material or cut foam.

5. The heating device according to claim 1, wherein said carrier layer of said heating mat is arranged to be air permeable.

6. The heating device according to claim 5, wherein said carrier layer of said heating mat is formed of reticulated foam or is provided with perforations in order to ensure air permeability.

7. (canceled)

8. The heating device according to claim 1, wherein said heating conductor is a stranded conductor comprising at least 200 metal filaments.

9. The heating device according to claim 1, wherein each of said metal filaments has a diameter of from 100 nm to 100 m.

10. Motor A motor vehicle seat comprising: a base body of foam; a seat cover; and a heating device disposed between said base body of foam and said seat cover, said heating device comprising; a heating mat having a carrier layer which comprises a first surface and a second surface opposite said first surface, said second surface carrying a heating conductor for generating heat, and said heating conductor extending over a heating area; and a seat cover upholstery comprising a foam layer; wherein said second surface of said carrier layer faces said seat cover upholstery, and said first surface of said carrier layer faces said seat cover and is in direct contact with the seat cover; and wherein said heating mat is sewn by stitches going through said seat cover, said heating mat, and said seat cover upholstery to form seams extending through said heating area.

11. The motor vehicle seat according to claim 10, wherein said heating conductor is a stranded conductor comprising at least 200 metal filaments.

12. The motor vehicle seat according to claim 10, wherein each of said metal filaments has a diameter of from 100 nm to 100 m.

13. The motor vehicle seat according to claim 10, comprising a plurality of parallel first seams and, at an angle with respect to the first seams, a second plurality of parallel seams which together form a diamond pattern on said seat cover.

14. The heating device according to claim 1, wherein said heating conductor is a stranded conductor comprising at least 100 metal filaments.

15. The motor vehicle seat according to claim 10, wherein said heating conductor is a stranded conductor comprising at least 100 metal filaments.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Embodiments of the heating device will now be described with reference to the drawings in which:

[0013] FIG. 1 is a partial view of a motor vehicle seat in cross-section including a heating device according to the prior art;

[0014] FIG. 2A is a perspective view of a motor vehicle seat including having a seat cover, a heating device, and a pattern of seams for attaching the heating device to the seat cover;

[0015] FIG. 2B is an enlarged view of the seat cover and seams of FIG. 2A;

[0016] FIG. 3A is a partial cross-sectional view of a motor vehicle seat of FIG. 2A, as taken along line 3A-3A, illustrating the motor vehicle seat including a heating device according to an embodiment of the invention;

[0017] FIG. 3B is a partial cross-sectional view of a motor vehicle seat of FIG. 2A, as taken along line 3B-3B;

[0018] FIG. 4A is a lower perspective exploded view of a portion of the motor vehicle seat of FIG. 2A;

[0019] FIG. 4B is an upper perspective exploded view of a portion of the motor vehicle seat of FIG. 2A; and

[0020] FIG. 5 is an enlarged partial view of a heating conductor of one embodiment of the heating device.

DETAILED DESCRIPTION

[0021] FIGS. 2A and 2B show a perspective view of a motor vehicle seat 50 having a seat bottom 14 and a seat back 16, with each of the seat bottom 14 and the seat back 16 having a seat cover 8. In this embodiment, the motor vehicle seat 50 further includes a plurality of seams 12 which include a plurality of parallel first seams 13a and a second plurality of parallel seams 13b angularly displaced at an angle with respect to the first seams 13a to form a diamond pattern 24. However, it is contemplated that the seams 12 may not intersect one another and/or the seams may be non-linear, such as a series of concentric seams or undulating seams. As described in detail below, the dense pattern of seams 12 can hold the seat cover 8 and a heating device 5 closely against one another in a heating area 52 to increase the amount of heat transferred from the heating device 5 to the seat cover 8 and a passenger seated on the seat cover 8.

[0022] FIGS. 3A and 3B illustrate partial views of the motor vehicle seat 50 in cross-section, with the seat 50 including the heating area 52 and the heating device 5 extending over the heating area 52. The heating device 5 includes a seat cover upholstery 4 made of foam. It is contemplated that the seat cover upholstery may be formed from other suitable materials. The heating device 5 further includes a heating mat 6. The heating mat 6 includes a carrier layer 18 having a first surface 18a facing the seat cover 8 such that the first surface is directed toward a passenger seated on the seat cover 8. The carrier layer 18 further includes a second surface 18b, which is opposite to the first surface 18a and faces the seat cover upholstery 4, such that the second surface 18b faces away from a passenger seated on the seat cover 8.

[0023] As best shown in FIGS. 4A and 4B, the heating mat 6 carries on its second surface 18b facing the seat cover upholstery 4 a heating conductor 20. The heating conductor 20 is connected to the carrier layer 18 by gluing or stitching. In this embodiment, the first surface 18a of the carrier layer 18, which faces the seat cover 8, is free of the heating conductor 20. However, in other embodiments, the heating conductor may be carried on the first surface or both the first and second surfaces of the carrier layer. The carrier layer of the heating mat may consist of felt, fleece, woven material or cut foam.

[0024] As shown in FIG. 3A, the stitches 13 of the seam 12 are applied such that they pierce through the seat cover 8, the heating mat 6, and the seat cover upholstery 4.

[0025] As shown in FIG. 5, the heating conductor 20 is formed as a stranded conductor 22 comprising a plurality of individual filaments 24, for example stainless steel filaments. The heating conductor 20 may also consist of several stranded conductors 22 which themselves are stranded with each other. In any case the heating conductor 20 has at least 100 individual metal filaments 24. The diameter of the individual filaments 24 is within the range from 100 nm to 100 m. With the heating conductor 20 formed in this manner by a plurality of individual elements it is possible to apply seams 12 to the heating area, with seams crossing the extension of the heating conductor 20, without causing damages to the heating conductor 20 by the sewing process which could affect the performance of the heating conductor 20. It turned out that, if a needle hits a heating conductor 20 directly, the vast majority of the individual filaments 24 of the heating conductor 20 is displaced or pushed aside, and that damages can only occur for a few individual filaments 24. If a few individual filaments 24 are damaged the performance of the heating conductor 20 as whole is not reduced.

[0026] For this reason it is possible for a motor vehicle seat in which between base body of foam and seat cover a heating device 5 according to the present invention is placed, to provide the heating area with a dense pattern of seams 12, as is for example the diamond pattern illustrated in FIG. 2B. In this manner a close and intimate contact of seat cover and heating mat may be achieved in the entire heating area. It was found that by the seams in the heating area the heating power at the surface of the seat cover is almost doubled compared to the situation in which seams are extending only outside of the heating area.

[0027] Because the first surface 18a of the heating mat 6 is in direct contact with the seat cover 8 and the heating conductor 20 comprises a sufficient number of individual filaments 22 that remain unbroken when the heating conductor 20 is directly hit by a needle when the seams 12 are formed, a substantially improved efficiency of the heating device 5 is achieved.

[0028] The invention has been described in an illustrative manner, and it is to be understood that the terminology which has been used is intended to be in the nature of words of description rather than of limitation. As is now apparent to those skilled in the art, many modifications and variations of the subject invention are possible in light of the above teachings. It is, therefore, to be understood that within the scope of the appended claims, wherein reference numerals are merely for convenience and are not to be in any way limiting, the invention may be practiced otherwise than as specifically described.