Device and method for automatically preventing misting of the windscreen of a vehicle

• US 20040040321A1
• Filed: 05/28/2003
• Published: 03/04/2004
• Est. Priority Date: 05/29/2002
• Status: Active Grant

• Current Assignee: C.R.F. Societa Consortile Per Azioni
• Original Assignee: C.R.F. Societa Consortile Per Azioni
• Inventors: Malvicino, Carloandrea, Mola, Stefano, Lo Presti, Giulio, Bisceglia, Gennaro
• Granted Patent: US 7,102,501 B2
• Time in Patent Office: Days
• US Class Current: 62/156
• CPC Class Codes: B60H 1/00785 by the detection of humidity or frost

Abstract

There is described a device for automatically preventing misting of the windscreen of a vehicle, wherein a number of sensors determine ambient conditions capable of misting the windscreen, and, upon such ambient conditions occurring, an electronic central control unit automatically activates the air-conditioning system of the vehicle to direct a stream of hot air onto the windscreen to raise its temperature and so prevent it from misting.

Claims

1. ) A device (1) for preventing misting of the windscreen (2) of a vehicle (3), characterized by comprising:

sensor means (4, 6, 7) for detecting ambient conditions capable of misting said windscreen (2); and

intervention means (8, 9), which are activated automatically, upon said ambient conditions occurring, to prevent misting of said windscreen (2).

2. ) A device as claimed in claim 1, characterized in that said intervention means (8, 9) comprise ambient condition altering means (9), which are activated automatically, upon said ambient conditions occurring, to alter at least one of said ambient conditions, at least in the vicinity of said windscreen (2).

3. ) A device as claimed in claim 1, characterized in that said intervention means (8, 9) are activated when a predetermined relationship exists between the temperature of the windscreen (Tv) and a dew point temperature (Tr).

4. ) A device as claimed in claim 3, characterized in that said predetermined relationship is defined by the temperature of the windscreen (Tv) being below the dew point temperature (Tr).

5. ) A device as claimed in claim 1, characterized in that said sensor means (4, 6, 7) comprise:

internal-temperature sensor means (4) indicating the temperature (Ti) inside the passenger compartment (5) of said vehicle (3);

external-temperature sensor means (6) indicating the temperature (Te) outside said vehicle (3); and

humidity sensor means (7) indicating the humidity (UR) inside the passenger compartment (5) of said vehicle (3).

6. ) A device as claimed in claim 5, characterized in that said intervention means (8, 9) comprise calculating means (20, 30) for calculating the temperature of the windscreen (Tv) as a function of the temperature (Ti) inside the passenger compartment (5) of said vehicle (3), and of the temperature (Te) outside said vehicle (3), and for calculating the dew point temperature (Tr) as a function of the temperature (Ti) and humidity (UR) inside the passenger compartment (5) of said vehicle (3).

7. ) A device as claimed in claim 6, characterized in that said intervention means (8, 9) also comprise comparing means (40) for comparing the temperature of the windscreen (Tv) with the dew point temperature (Tr), and for activating said intervention means (8, 9) when the temperature of the windscreen (Tv) is below the dew point temperature (Tr).

8. ) A device as claimed in claim 6, characterized in that said intervention means (8, 9) also comprise air-conditioning means (9);

and control means (50) for controlling said air-conditioning means (9) so as to direct a stream of hot air onto said windscreen (2).

9. ) A method of preventing misting of the windscreen of a vehicle, characterized by comprising the steps of:

determining ambient conditions capable of misting said windscreen (2); and

automatically activating intervention means (8, 9), upon said ambient conditions occurring, to prevent misting of said windscreen (2).

10. ) A method as claimed in claim 9, characterized in that said step of automatically activating intervention means (8, 9) comprises the step of automatically activating ambient condition altering means (8, 9) to alter at least one of said ambient conditions, at least in the vicinity of said windscreen (2).

11. ) A method as claimed in claim 9, characterized by comprising the step of activating said intervention means (8, 9) when a predetermined relationship exists between the temperature of the windscreen (Tv) and a dew point temperature (Tr).

12. ) A method as claimed in claim 11, characterized in that said predetermined relationship is defined by the temperature of the windscreen (Tv) being below the dew point temperature (Tr).

13. ) A method as claimed in claim 9, characterized in that said step of determining ambient conditions capable of misting said windscreen (2) comprises the steps of:

determining the temperature (Ti) inside the passenger compartment (5) of said vehicle (3);

determining the temperature (Te) outside said vehicle (3); and

determining the humidity (UR) inside the passenger compartment (5) of said vehicle (3).

14. ) A method as claimed in claim 13, characterized in that said step of automatically activating said intervention means (8, 9) comprises the steps of:

calculating the temperature of the windscreen (Tv) as a function of the temperature (Ti) inside the passenger compartment (5) of said vehicle (3), and of the temperature outside said vehicle (3); and

calculating the dew point temperature (Tr) as a function of the temperature (Ti) and humidity (UR) inside the passenger compartment (5) of said vehicle (3).

15. ) A method as claimed in claim 14, characterized in that said step of automatically activating said intervention means (8, 9) also comprises the steps of:

comparing the temperature of the windscreen (Tv) with the dew point temperature (Tr); and

automatically activating said intervention means (8, 9) when the temperature of the windscreen (Tv) is below the dew point temperature (Tr).

16. ) A method as claimed in claim 14, characterized in that said step of automatically activating said intervention means (8, 9) comprises the step of:

controlling air-conditioning means (9) of said vehicle (3) so as to direct a stream of hot air onto said windscreen (2).