Sensor means for determining the interior humidity and fogging up tendency, and fastening device of the sensor means

• US 20050178200A1
• Filed: 02/03/2005
• Published: 08/18/2005
• Est. Priority Date: 02/16/2004
• Status: Active Grant

• Current Assignee: Sitronic Gesellschaft Fur Elekrotechnische
• Original Assignee: Sitronic Gesellschaft Fur Elekrotechnische
• Inventors: Stauss, Gerold, Raab, Christoph
• Granted Patent: US 7,197,927 B2
• Time in Patent Office: Days
• US Class Current: 73/335.20
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 2110/20 Humidity
• CPC Class Codes: G01N 25/66 by investigating dew-point

Abstract

A sensor means is proposed to determine an interior humidity and/or an interior volume delimited by a wall, in particular, of a vehicle passenger compartment 3, and a fogging up tendency of an inner surface of the wall, in particular, of a window 5 of the vehicle passenger compartment 3, with a dew point sensor 10 having a humidity sensor element 1 and a temperature sensor 2, wherein the humidity sensor element 1 and the temperature sensor 2 are thermally coupled, and a surface temperature sensor 4, wherein the dew point sensor 10 is designed to measure the air humidity and the room temperature of the interior volume and the surface temperature sensor 4 is designed to measure the temperature of the inner surface.

Claims

1. Sensor for determining an interior humidity or an interior dew point of an interior volume delimited by a wall, in particular, of a vehicle passenger compartment, and a fogging up tendency of an inner surface of the wall, in particular, of a window of the vehicle passenger compartment, said sensor comprising:

a dew point sensor having a humidity sensor element measuring air humidity of the interior volume,

a temperature sensor measuring room temperature of the interior volume; and

a surface temperature sensor measuring a temperature of the inner surface.

2. Sensor according to claim 1, wherein the surface temperature sensor is a contacting sensor, including an NTC or PTC sensor element.

3. Sensor according to claim 2, further comprising a material having good heat conducting properties disposed between the surface temperature sensor and the wall.

4. Sensor according to claim 2, wherein the surface temperature sensor is thermally decoupled from the dew point sensor.

5. Sensor according to claim 1, wherein the sensor comprises a printed board and wherein the dew point sensor is mounted to the printed board.

6. Sensor according to claim 1, wherein the sensor comprises a flexible heat conducting sheet with strip conductors, and wherein the surface temperature sensor is mounted to the sheet.

7. Sensor according to claim 5, wherein the sheet is electrically connected to the printed board.

8. Sensor according to claim 5, wherein the surface temperature sensor is mounted to the printed board.

9. Sensor according to claim 8, wherein the printed board has an elongated basic shape consisting of a protruding end and a support surface, and wherein the surface temperature sensor is mounted to the protruding end and the dew point sensor is disposed on the support surface.

10. Sensor according to claim 9, further comprising an evaluation unit disposed on the printed board in particular on the support surface, and is designed to calculate the dew point from the measured signal of the dew point sensor.

11. Sensor according to claim 10, wherein the evaluation unit is designed to determine the surface temperature from the measured signal of the surface temperature sensor, and wherein the determined surface temperature is corrected in response to signals of a sun sensor, a rain sensor, an external temperature sensor and/or a speed sensor.

12. Sensor according to claim 11, wherein the evaluation unit is designed to correct the determined surface temperature using a function of the measured signal of the surface temperature sensor and of the temperature sensor.

13. Sensor according to claim 12, wherein the evaluation unit is designed to correct the determined surface temperature through addition of the function.

14. Sensor according to claim 12, wherein the function is the difference, weighted by a constant, of the measured signals of the surface temperature sensor and of the temperature sensor.

15. Sensor according to claim 11, wherein the evaluation unit is designed to compare the calculated dew point with the determined surface temperature to determine the fogging up tendency.

16. Sensor according to claim 1, wherein the evaluation unit is designed to emit a warning if a relative air humidity value is exceeded at a mounting point of the surface temperature sensor.

17. Sensor according to claim 1, wherein the evaluation unit comprises a Kline, CAN, or LIN bus interface with a vehicle air conditioning control system.

18. Sensor according to claim 1, wherein the sensor comprises a housing having a lid with a humidity permeable diaphragm and wherein the dew point sensor is disposed within the housing.

19. Sensor according to claim 1, wherein the sensor comprises a sensor holder with a front surface, and wherein the surface temperature sensor is mounted to the front surface such that the surface temperature sensor can be mounted in a thermally conducting manner to the inner surface, through gluing of the front surface to the inner surface.

20. Sensor according to claim 19, wherein the front surface comprises a bonding sheet comprising a removable protective sheet.

21. Fastening device comprising:

a sensor for determining an interior humidity or an interior dew point of an interior volume delimited by a wall, in particular, of a vehicle passenger compartment, and a fogging up tendency of an inner surface of the wall, in particular, of a window of the vehicle passenger compartment, said sensor comprising

a dew point sensor having a humidity sensor element, measuring air humidity of the interior volume, a temperature sensor measuring room temperature of the interior volume and;

a surface temperature sensor measuring a temperature of the inner surface; and

a rear mirror foot of a vehicle rear mirror

wherein the dew point sensor is mounted within the fastening device.

22. Fastening device with a sensor arrangement, comprising a cover designed as rear mirror foot, into which an electronic unit of the sensor arrangement is installed, a tubular projection and a sensor holder which can be pushed onto the projection with a front surface which is adapted to an inner surface of a vehicle window, and wherein the sensor holder is displaceably disposed on the projection and a front surface abuts the inner surface of the vehicle window through displacing the sensor holder when the rear mirror foot is mounted in a vehicle passenger compartment.

23. Fastening device according to claim 22, wherein the sensor arrangement comprises a sensor for determining an interior humidity or an interior dew point of an interior volume delimited by a wall, in particular, of a vehicle passenger compartment, and a fogging up tendency of an inner surface of the wall, in particular, of a window of the vehicle passenger compartment, said sensor comprising

a dew point sensor having a humidity sensor element, measuring air humidity of the interior volume, a temperature sensor measuring room temperature of the interior volume and;

a surface temperature sensor measuring a temperature of the inner surface; and

wherein the surface temperature sensor is mounted to the front surface such that the surface temperature sensor can be mounted in a thermally conducting manner to the inner surface of the vehicle window through gluing the front surface to the inner surface, and the dew point sensor is disposed within the housing.

24. Fastening device in accordance with claim 22 further comprising a housing with a holder, wherein a flexible and heat conducting silicon adhesive substance, is disposed on a front surface of a projecting end of a printed board at a mounting point of the surface temperature sensor, and the housing with holder is designed to force the printed board including substance to an inner windscreen surface.

25. Fastening device according to claim 24, wherein the flexible heat conducting substance is designed as cap which can be pushed onto the end of the printed board at the mounting point of the surface temperature sensor.

26. Fastening device according to claim 24, further comprising a metal part, mounted, to a mounting point of the surface temperature sensor.