Vehicle having an electric heating device

Abstract

A vehicle has an electric heating device which in operation reaches a temperature of more than 50 C., and includes a flat perforated decorative layer which is disposed on a front face of the heating device. Because of the perforation of the decorative layer, the heating device can radiate infrared radiation through holes provided in the decorative layer directly into a passenger compartment of the vehicle. The vehicle also has a reflector layer which is disposed on a rear face of the heating device facing away from the front face and is provided in order to reflect infrared radiation emitted by the heating device in the direction of the passenger compartment.

Claims

1. A vehicle, comprising: an electric heating device which, in operation, reaches a temperature of greater than 50 C., wherein the electric heating device has a front side facing a passenger compartment of the vehicle; a planar, perforated decorative layer arranged on the front side of the electric heating device so as to be disposed between the electric heating device and the passenger compartment; a reflector layer arranged on a rear side of the electric heating device, the rear side facing away from the front side, wherein the electric heating device is configured to emit infrared radiation through holes of the planar, perforated decorative layer directly into a passenger compartment of the vehicle due to the porosity of the decorative layer, and the reflector layer is configured to reflect infrared radiation, emitted by the electric heating device, in a direction of the passenger compartment, wherein an air gap is disposed between the electric heating device and the planar, perforated decorative layer such that a planar space is provided between and parallel to the electric heating device and the planar, perforated decorative layer.

2. The vehicle according to claim 1, further comprising: an insulation layer arranged on a rear side of the reflector layer, the rear side facing away from the electric heating device, wherein the insulation layer is configured to reduce heat emission into a vehicle compartment.

3. The vehicle according to claim 1, wherein the decorative layer has a perforation ratio of at least 20%.

4. The vehicle according to claim 1, wherein the decorative layer has a perforation ratio of at least 30%.

5. The vehicle according to claim 1, wherein the decorative layer has a perforation ratio of at least 40%.

6. The vehicle according to claim 1, wherein the decorative layer is formed of a woven, weft-knitted, or warp-knitted fabric.

7. The vehicle according to claim 3, wherein the decorative layer is formed of a woven, weft-knitted, or warp-knitted fabric.

8. The vehicle according to claim 1, wherein the decorative layer has a thermal capacity per unit of surface area less than or equal to $1\frac{\mathrm{KJ}}{m^2.Math.K}.$

9. The vehicle according to claim 1, wherein the decorative layer has a thermal capacity per unit of surface area less than or equal to ${0.3}_{m^2.Math.K}^{\mathrm{KJ}}.$

10. The vehicle according to claim 1, wherein the decorative layer has a thermal conductivity less than or equal to ${0.5}_{m.Math.K}^W.$

11. The vehicle according to claim 1, wherein the decorative layer has a thermal conductivity less than or equal to ${0.1}_{m.Math.K}^W.$

12. The vehicle according to claim 1, wherein the electric heating device is a heating film.

13. The vehicle according to claim 1, wherein the electric heating device includes paper and carbon fiber components.

14. The vehicle according to claim 1, wherein the electric heating device comprises a carrier substrate and an electrically conductive layer.

15. The vehicle according to claim 1, wherein the electric heating device has a thermal capacity per unit of surface area less than or equal to $3_{\mathrm{KJ}}^{m^2.Math.K}.$

16. The vehicle according to claim 1, wherein the electric heating device has a thermal capacity per unit of surface area less than or equal to $1_{m^2.Math.K}^{\mathrm{KJ}}.$

17. The vehicle according to claim 1, wherein the electric heating device is configured to reach a temperature of 70 C. during operation.

18. The vehicle according to claim 1, wherein the electric heating device is configured to reach a temperature of 100 C. during operation.

19. The vehicle according to claim 1, wherein the electric heating device is configured to reach a temperature of 120 C. during operation.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 shows the schematic layout of an electric heating device according to an embodiment of the invention.

DETAILED DESCRIPTION OF THE DRAWINGS

(2) An electric heating device according to the invention can be integrated into a vehicle door, an instrument panel, a vehicle roof, etc.

(3) The core component of an electric heating device is an infrared radiator 1 which can be formed, for example, by an electrically conductive, resistive heating film. Heat is generated when electric current flows through the heating film 1. The heating film 1 is arranged behind a decorative layer 3 when seen from the passenger compartment 2.

(4) The decorative layer 3 has a relatively high optical transparency, and the perforation ratio of the decorative layer lies, for example, in the range of at least 20%, at least 30% or at least 40%. The decorative layer can be embodied as a woven, weft-knitted or warp-knitted fabric, for example.

(5) An air gap 4 can be provided between the decorative layer 3 and the heating film 1. Such an air gap 4 need not necessarily be provided, however. In any case, the decorative layer 3 should be made of a material that is at least temperature-resistant enough that it is not damaged by continuous contact with the heating film 1. Depending on the operating temperature of the heating film 1, the material of the decorative layer must therefore be able to withstand temperatures of at least 70 C. or 120 C.

(6) A layer (IR reflector) 5 that reflects infrared radiation is arranged on a rear side of the heating film 1 facing away from the decorative layer 3. The reflector layer 5, which can be formed by an aluminum foil or the like, is provided for the purpose of reflecting heat in the direction of the passenger compartment 2. This layer or film can be optimized such that it has a reflection coefficient that is as high as possible.

(7) To minimize heat losses into a vehicle structure 6 (not shown in further detail), or prevent such losses to the greatest possible extent, an insulation layer 7 is provided on a rear side of the reflector layer 5 facing away from the heating device 1.

(8) When a body part, such as a finger 8, for example, is now pressed against the decorative layer 3, it comes to rest against the heating film 1. In order to ensure that no burns can occur during contact with the decorative layer 3, the thermal capacity of the decorative layer 3 by unit of surface area should be less than or equal to

(9) $1\frac{\mathrm{KJ}}{m^2.Math.K},$
particularly less than or equal to

(10) 0$0.3\frac{\mathrm{KJ}}{m^2.Math.K}.$

(11) Alternatively or in addition, a provision should be made that the thermal conductivity of the decorative layer is less than or equal to

(12) $0.5\frac{W}{m.Math.K},$
preferably even less than or equal to

(13) $0.1\frac{W}{m.Math.K}.$

(14) Alternatively or in addition, a further provision should be made that the thermal capacity of the heating film 1 by unit of surface area is less than or equal to

(15) $3\frac{\mathrm{KJ}}{m^2.Math.K},$
particularly less than or equal to

(16) $1\frac{\mathrm{KJ}}{m^2.Math.K}.$

(17) Insofar as individual or all of the abovementioned parameters are considered when setting up the infrared heater, the heating film 1 can be operated without problems at temperatures of up to 90 C., 120 C. or possibly even at higher temperatures without danger of burns.

(18) The foregoing disclosure has been set forth merely to illustrate the invention and is not intended to be limiting. Since modifications of the disclosed embodiments incorporating the spirit and substance of the invention may occur to persons skilled in the art, the invention should be construed to include everything within the scope of the appended claims and equivalents thereof.