METHODS OF DEPLOYING A COVER UTILIZING ACTIVE MATERIAL AND AN EXTERNAL HEAT SOURCE

• US 20090072575A1
• Filed: 03/31/2008
• Published: 03/19/2009
• Est. Priority Date: 09/18/2007
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (General Motors Company)
• Inventors: Browne, Alan L., Johnson, Nancy L.
• Granted Patent: US 8,109,318 B2
• Time in Patent Office: Days
• US Class Current: 296/97.700
• CPC Class Codes: B60J 11/025 specially adapted for covering vehicle parts, e.g. for doors, windows or windscreens
• CPC Class Codes: B60J 11/08 for windows or windscreens antiglare equipment B60J3/00
• CPC Class Codes: B60J 3/002 External sun shield, e.g. awning or visor

Abstract

Methods of deploying and stowing a cover coupled to an actuator comprising active material, includes the steps of heating the material with an external heat source, so as to cause a change in physical property and deploying the cover due to the change, and preferably includes accelerating the heating of the material by focusing the energy of the source with a lens or prism, engaging the cover with an input device and retracting the cover upon input, releasing stored energy as a result of the change, or further deploying the cover by use of a ratcheting mechanism, use of a timer for delayed actuation, use of a sensor configured to determine a condition, such as an opened door or the presence of an occupant, interconnecting to a windshield wiper, immersing the actuator in a heated fluid, and conduction heating the actuator through contact with a heated panel.

Claims

1. A method of deploying a cover having an active material based actuator utilizing an external heat source spaced from the cover, said method comprising the steps of:

a. securing the cover relative to the source such that at least a portion of the actuator is thermally coupled to the source, said at least portion presenting a first temperature;

b. heating said at least portion with the heat source, so as to achieve a second temperature and cause a change in a physical property of the actuator; and

c. deploying the cover as a result of the change, when the second temperature is achieved.

2. The method as claimed in claim 1, wherein the heat source is the sun, the actuator is exposed and thermally coupled to radiant heat energy provided thereby, and step a) further includes securing the cover relative to at least one glazing region defining an area of radiation transparency, so as to prevent the transmission of radiation through at least a portion of the area when deployed.

3. The method as claimed in claim 2, wherein step b) further includes the steps of focusing the radiant heat energy through a lens or prism, so as to accelerate the heating of the actuator.

4. The method as claimed in claim 1, further comprising step:

d. allowing the actuator to cool to a third temperature less than the second whereat the change is reversed, and stowing the cover as a result of the reversal, when the third temperature is achieved.

5. The method as claimed in claim 1, further comprising step:

d. engaging the cover with an input device configured to receive an input from a user, and causing the cover to stow upon receipt of the input after the second temperature is achieved.

6. The method as claimed in claim 5, wherein said cover is adapted for use with a vehicle having at least one door, and the device and door are cooperatively configured such that the input is the opening of the door.

7. The method as claimed in claim 1, wherein step c) further includes releasing stored energy as a result of the change, and deploying the cover as a result of releasing said energy.

8. The method as claimed in claim 7, wherein step c) further includes releasing energy stored in a biased spring.

9. The method as claimed in claim 1, wherein the actuator is drivenly coupled to a ratcheting mechanism, and step c) further includes driving the ratcheting mechanism and deploying the cover as a result of driving the ratcheting mechanism.

10. The method as claimed in claim 1, wherein step b) further includes the steps of immersing the actuator in a fluid and heating the actuator by initially heating the fluid.

11. The method as claimed in claim 1, wherein step b) further includes the steps of contacting the actuator with at least one panel and heating the actuator by initially heating the panel.

12. The method as claimed in claim 1, wherein step b) further includes the steps of connecting the actuator to at least one pyroelectric element, heating at least one of said at least one pyroelectric element so as to generate an electric current, transmitting the current to the actuator, and resisting the current at the actuator so as to heat said at least portion.

13. The method as claimed in claim 1, wherein step c) further includes the steps of deploying the cover to a deployed condition, and locking the cover in the deployed condition with a locking pin.

14. The method as claimed in claim 1, wherein the cover is adapted for use with a front windshield of a vehicle having at least one swingable windshield wiper, and step c) further includes interconnecting with the wiper and cover, and causing the wiper to swing a predetermined angular distance, as a result of the change.

15. The method as claimed in claim 1, wherein the actuator is communicatively coupled to a timer, and step c) further includes the steps of deploying the cover after a delay period has expired.

16. The method as claimed in claim 1, wherein the actuator is communicatively coupled to at least one sensor configured to selectively transmit data to the actuator, and step c) further includes the steps of deploying the cover only after receiving the data.

17. The method as claimed in claim 1, wherein the actuator is coupled to an obscuring element and further configured to deploy the element, when the second temperature is achieved, and step c) further includes the steps of deploying the cover and element to a deployed condition, wherein the element blocks the exposure of the actuator from the source, so as to accelerate cooling of the actuator.

18. The method as claimed in claim 17, wherein a second active-material based actuator is drivenly coupled to the obscuring element, presents a first element temperature, is configured so as to be exposed to and heated by the source, when the element is in the deployed condition, and further configured to retract the element when heated to a second element temperature greater than the first, so that the actuator is re-exposable to the source.

19. A method of deploying a cover utilizing an external heat source spaced from the cover, wherein said cover is adapted for use with a vehicle presenting at least one glazing and defining an interior compartment, and includes an active-material based actuator communicatively coupled to the compartment, said method comprising the steps of:

a. securing the cover relative to the source such that the actuator is exposed and thermally coupled to the source, said actuator presenting a first temperature;

b. heating the actuator with the heat source, so as to achieve a second temperature whereat the actuator is caused to undergo a change in physical property;

c. determining a condition status within the compartment and conveying the condition to the actuator; and

d. selectively deploying the cover as a result of the change, when the second temperature is achieved, based on the condition status.

20. A method of deploying and retracting a cover utilizing an external heat source spaced from the cover, wherein said cover is adapted for use with a vehicle presenting at least one glazing and door, is communicatively coupled to the door, and includes an active-material based actuator, said method comprising the steps of:

a. securing the cover relative to the glazing and source such that the actuator is exposed and thermally coupled to the source, said actuator presenting a first temperature;

b. heating the actuator with the heat source, so as to achieve a second temperature whereat the actuator is caused to undergo a change in physical property;

c. deploying the cover as a result of the change, so as to overlay at least a portion of the glazing, when the second temperature is achieved;

d. determining whether the door is opened or closed after deploying the cover; and

e. retracting the cover, when the door is opened or the actuator cools to a third temperature less than the second.