Method and circuit arrangement for operating an electric seat heating means of a vehicle

• US 5,948,297 A
• Filed: 08/25/1997
• Issued: 09/07/1999
• Est. Priority Date: 06/03/1993
• Status: Expired due to Fees

• Current Assignee: Wet Automotive Systems AG (Gentherm Incorporated)
• Original Assignee: Wet Automotive Systems AG (Gentherm Incorporated)
• Inventors: Haubner, Georg, Lorenzen, Gunter
• Primary Examiner(s): Walberg, Teresa
• Assistant Examiner(s): ROBINSON, DANIEL LEON
• Application Number:
  US08/917,233
• Time in Patent Office: 743 Days
• Field of Search: 219/202, 219/217, 219/201, 297/180.12
• US Class Current: 219/202
• CPC Class Codes: B60H 1/00285 for vehicle seats vehicle seats with heating or ventilation means independent from the HVAC system of the vehicle B60N2/56
• CPC Class Codes: B60N 2/5685 Resistance

Abstract

In a method and the arrangement for operating an electric seat heating apparatus of a vehicle, it is provided, with a view to optimizing the heat-up behavior, that the given heat-up time or temperature, respectively, being reached, the heating power is preset by a microprocessor as a function of a field of characteristic curves or tables stored in a non-volatile memory such that for seats that differ in size, upholstery, and surface quality, the optimally to be supplied heating power or heating time, respectively, is empirically detected as a function of the desired seat temperature on the surface of the seating face or the rear and is stored in the non-volatile memory in the form of curves or tables, that a curve or table is selected from the field of characteristic curves or tables, respectively, by the microprocessor as a function of a coding recorded by the microprocessor, of the respective seat to the heated, and that then the power supply to the respective seat to be actually heated takes place in accordance with the selected curves or table.

Claims

1. A method for operating an electric seat heating means for a vehicle, comprising the steps of:

heating an unheated vehicle seat (1) to a maximally available heating power in a first phase after starting the vehicle,

switching to controlled operation of the seat heating means after a given heat-up time or temperature, respectively is reached,

presetting the heating power to reach the given heat-up time or temperature, respectively, with a microprocessor (MC) as a function of a field of characteristic curves or tables stored in a non-volatile memory

wherein, for a seat (1) that differs in size, upholstery, and surface quality, the optimum supplied heating power or heating time, respectively, is empirically detected as a function of the desired seat temperature on the surface of the seat and is stored in the non-volatile memory in the form of curves or tables,

a curve or table is selected from the field of characteristic curves or tables, respectively, by the microprocessor as a function of a coding recorded by the microprocessor (MC), of the a seat (1) to be heated,

the power supply to the seat heated takes place in accordance with the selected curves or table, and

wherein operating data such as inside temperature, outside temperature, a temperature taken on the underside of the seat surface, whether a seat (1) is occupied by a person (4), running state of the vehicle, instantaneous voltage of the supply system, are recorded and taken into account for the selection of the curves or tables.

2. A method according to claim 1, wherein when switching to controlled operation, a control of the power supply takes place in dependence on the selected curve or table, respectively, independent of the measurement of an actual temperature.

3. A method according to claim 1, wherein the microprocessor (MC) selects the characteristic curve or the table, respectively, as a function of a desired temperature preset by a user (4).

4. A method according to claim 1, wherein the microprocessor (MC) selects the curve or table, respectively, in dependence on a stored coding individually entered by a user.

5. Method according to claim 1, wherein the selection of curves or tables, respectively, is combined with a seat position coding related to a person occupying a seat.

6. A method according to claim 1, wherein the seat (1) to be heated is identified by the control system via a serial interface.

7. A circuit arrangement in an electric seat heating means for a vehicle, comprising an unheated vehicle seat (1) heated to a maximally available heating power in a first phase after starting the vehicle, switching means for controlling operation of the heat means after a given heat-up time or temperature, respectively has been reached, a microprocessor and a non-volatile memory which store a plurality of heat-up curves or heat-up tables, respectively for selection, wherein said seat heating means is switched by an output of said microprocessor and wherein a serial interface is provided for identifying a vehicle seat to be heated.

8. A method of electrically heating a seat having thermal seat characteristics, the method comprising steps of:

providing a microprocessor controlling an electric heating power delivered to the seat, the microprocessor including a non-volatile memory;

installing in the memory a plurality of look-up tables or curves, each of the tables or curves determining the electric heating power as a function of time;

installing in the microprocessor a program for selecting one of the tables or curves stored in the memory;

first applying, in a heat-up phase, a maximum available electric heating power until a given heat-up temperature condition is reached or a given heat-up time interval is elapsed;

then selecting, according to at least one parameter, one of the tables or curves; and

controlling the electric heating power according to the selected one of the tables or curves.

9. The method according to claim 8, wherein the tables or curves include a controlled reduction portion and a steady-state portion.

10. The method according to claim 8, wherein the parameter includes occupancy of the seat by a person.

11. The method according to claim 8, wherein the parameter includes manual adjustment.

12. The method according to claim 8, wherein the parameter includes ambient temperature.

13. The method according to claim 8, wherein the parameter includes a thermal characteristic of the seat.

14. The method according to claim 13, including a step of providing an interface between the seat and the microprocessor, whereby the seat is digitally identified to the microprocessor and the thermal characteristic is available to the microprocessor.

15. The method according to claim 8, wherein the parameter does not include a temperature measured on a surface of the seat.

16. The method according to claim 8, wherein the parameter includes a temperature measured on an underside of the seat.

17. The method according to claim 8, wherein the parameter includes a duration or a maximum temperature of the heat-up phase.

18. The method according to claim 8, wherein the parameter includes electrical system operating characteristics.

19. The method according to claim 8, wherein the parameter includes a combination of ambient temperature and thermal resistance of the seat.