Temperature sensor for power supply

• US 20060098371A1
• Filed: 11/08/2004
• Published: 05/11/2006
• Est. Priority Date: 11/08/2004
• Status: Active Grant

• Current Assignee: RRC power solutions GmbH
• Original Assignee: RRC power solutions GmbH
• Inventors: Hackett, Gareth J., Wambsganss, Peter M.
• Granted Patent: US 7,408,132 B2
• Time in Patent Office: Days
• US Class Current: 361/103
• CPC Class Codes: H02H 5/042 using temperature dependent resistors

Abstract

A temperature sensor, such as a thermistor, senses the temperature inside a power source connector, or other portion, of a power supply. This sensed temperature may then be used to determine if the output power should be reduced or switched off in order to avoid overheating of the connector, or other portion of the power supply. Overheating of the power supply may occur, for example, if contact between the connector and a cigarette lighter power receptacle is incomplete. A microcontroller may be used to monitor the temperature sensed by the temperature sensor and reduce or disable the power supply if the temperature is above a threshold temperate. Accordingly, heat damage to the plastic components of the power supply, the cigarette lighter receptacle, may be reduced.

Claims

1. A power supply configured to receive electrical power from a cigarette lighter receptacle in a vehicle, the power supply comprising:

a power supply housing configured to house a power module,a microcontroller electronically coupled to the power module and configured to control a power signal transmitted from the power module; and

a temperature sensor disposed outside of the power supply housing and configured to sense a temperature of a portion of the power supply and transmit an indication of the sensed temperature to the microcontroller.

2. The power supply of claim 1, wherein the microcontroller is further configured to reduce a level of the power signal in response to determining that the sensed temperature is above a predetermined threshold temperature.

3. The power supply of claim 1, wherein the power signal comprises a voltage level and a current level.

4. The power supply of claim 2, wherein the predetermined threshold temperature is selected from the group comprising:

about 80, 90, 100, 110, 120, 130, 140, and 150 degrees centigrade.

5. The power supply of claim 1, wherein the microcontroller is further configured to disable the power module in response to determining that the sensed temperature is above a predetermined threshold temperature.

6. The power supply of claim 1, further comprising a connector configured to couple the power module with the power source, wherein the temperature sensor is disposed in the connector.

7. The power supply of claim 6, wherein the temperature sensor transmits the indication of the sensed temperature to the microcontroller via one or more electrical connection lines coupling the connector and the power supply housing.

8. The power supply of claim 1, wherein the temperature sensor comprises a negative temperature coefficient resistor.

9. The power supply of claim 1, wherein the temperature sensor comprises an integrated circuit.

10. A method of reducing overheating of a power supply configured to receive a power signal from a vehicle through a cigarette lighter receptacle, the method comprising:

sensing a temperature of at least a portion of the power supply,determining if the sensed temperature is greater than a predetermined threshold; and

reducing a power level of the power supply in response to determining that the sensed temperature is greater than a predetermined threshold temperature.

11. The method of claim 10, wherein the at least a portion of the power supply comprises a connector configured to engage with the cigarette lighter receptacle.

12. The method of claim 10, wherein the at least a portion of the power supply comprises an electrical cable connecting the power supply to a power source connector.

13. The method of claim 10, wherein the at least a portion of the power supply comprises an electrical cable connecting the power supply to an electronic device connector.

14. The method of claim 10, wherein the predetermined threshold temperature is selected from the group comprising:

about 80, 90, 100, 110, 120, 130, 140, and 150 degrees centigrade.

15. A power supply comprising,a power module configured to convert a power signal received from a power source,a connector configured to couple the power module with the power source,a first temperature sensor disposed proximate the power module and configured to sense a temperature of the power module,a second temperature sensor disposed in the connector and configured to sense a temperature of the connector;

and

a power control module configured to reduce a power level of a power signal transmitted from the power supply in response to determining that the temperature of the connector is greater than a predetermined threshold temperature.

16. The power supply of claim 15, wherein the power level of the power signal transmitted from the power supply is reduced to about zero watts.

17. The power supply of claim 15, wherein the power control module comprises a microcontroller in data communication with the second sensor.

18. The power supply of claim 15, wherein the power control module is further configured to disable output of the power signal from the power supply in response to determining that the temperature of the power module is greater than another predetermined threshold temperature.

19. The power supply of claim 15, wherein the power supply is coupled to the power source via a cigarette lighter receptacle.

20. The power supply of claim 15, wherein the power supply is coupled to the power source via an in-seat power delivery receptacle.

21. A system for reducing overheating of a power supply configured to receive a power signal from a cigarette lighter receptacle in a vehicle, the system comprising:

means for sensing a temperature of at least a portion of the power supply,means for determining if the sensed temperature is greater than a predetermined threshold; and

means for reducing a power level of the power supply in response to determining that the sensed temperature is greater than a predetermined threshold temperature.

22. The system of claim 21, wherein the means for sensing is disposed in a connector configured to mechanically engage the cigarette lighter receptacle.