Composite backed prestressed mirror for solar facet

• US 6,739,729 B1
• Filed: 06/27/2000
• Issued: 05/25/2004
• Est. Priority Date: 06/27/2000
• Status: Expired due to Term

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Dean, David Lee, Blackmon, James Bertram
• Primary Examiner(s): Shafer, Ricky D.
• Application Number:
  US09/604,224
• Time in Patent Office: 1,428 Days
• Field of Search: 359/846, 359/847, 359/848, 359/851, 359/852, 359/853, 359/867, 359/868, 359/869, 359/870, 359/871, 359/883, 359/894, 428/332, 65/63, 651/02, 652/86, 652/87, 156/84, 156/85, 156/86, 156/168, 156/165, 156/196, 156/212, 156/285, 156/445
• US Class Current: 359/846
• CPC Class Codes: C03B 23/0357 by suction without blowing, e.g. with vacuum or by venturi effect
• CPC Class Codes: F24S 23/82 characterised by the material or the construction of the reflector
• CPC Class Codes: G02B 26/0825 the reflecting element being a flexible sheet or membrane, e.g. for varying the focus flexible mirrors for cosmetic use A45D42/24
• CPC Class Codes: G02B 7/183 specially adapted for very large mirrors, e.g. for astronomy, or solar concentrators
• CPC Class Codes: Y02E 10/40 Solar thermal energy, e.g. solar towers
• CPC Class Codes: Y10T 156/1002 with permanent bending or reshaping or surface deformation of self sustaining lamina

Abstract

A glass structure, such as a mirror facet, having a glass member, a composite structure and a support structure. The composite structure includes a rigid interlayer which is bonded to the glass member and exerts a compressive force thereon to place the glass member in compression. The support structure is used to mount the glass structure and prevents the glass member from collapsing due to the compressive force exerted by the rigid interlayer. The glass structure is particularly well adapted for use in forming heliostats, parabolic dishes, trough concentrators, or other like elements for use in solar power systems, and does not suffer from the limitations or prior forms of such devices.

Claims

1. A glass structure suitable for use in collecting and reflecting thermal energy in a solar power system, the glass structure comprising:

a glass member having a front surface and a rear surface, the glass member being formed such that the rear surface is at least partially arcuately shaped, wherein formation of the glass member places the rear surface in a state of tension; and

resin means applied to the rear surface of the glass member, the resin means curing to form a rigid interlayer that applies a compressive force to the glass member so that both the front and rear surfaces of the glass member are maintained in a state of compression.

2. The glass structure of claim 1, wherein the resin means is selected from a group of resins consisting of unsaturated polyesters, bismaleimides, epoxy vinyl esters and epoxies.

3. The glass structure of claim 1, wherein the resin means includes an inorganic filler.

4. The glass structure of claim 1, further comprising a reinforcing structure that is coupled to the rigid interlayer.

5. The glass structure of claim 4, wherein the reinforcing structure includes a reinforcing member and a resin.

6. The glass structure of claim 5, wherein the reinforcing member is a woven fiberglass.

7. The glass structure of claim 5, wherein the resin is selected from a group of resins consisting of unsaturated polyesters, bismaleimides, epoxy vinyl esters and epoxies.

8. The glass structure of claim 5, further comprising a securing structure coupled to the reinforcing structure and adapted for use in mounting the glass structure.

9. The glass structure of claim 1, wherein the glass member includes a glass panel having a thickness of about 0.001 inch to about 0.4 inch.

10. The glass structure of claim 1, wherein the glass member is a mirror and the glass structure is a mirror facet.

11. The glass structure of claim 1, further comprising a securing structure coupled to the rigid interlayer and adapted for use in mounting the glass structure.

12. The glass structure of claim 11, wherein the securing structure is formed from a metallic material.

13. A glass assembly comprising:

a glass structure with a planar front surface and a planar rear surface that is generally parallel to the front surface, the glass structure being deflected such that the front surface is in a state of compression and the rear surface is in a state of tension, the compression and tension occurring as a result of the deflection of the glass structure; and

a liquid resin applied to the rear surface of the glass structure, the resin curing to form a rigid interlayer, the resin shrinking as it cures to generate a compressive force that is applied to the rear surface of the glass structure, the compressive force generated by the resin being of sufficient magnitude so as to place the rear surface of the glass structure into a state of compression.

14. The glass assembly of claim 13, wherein the liquid resin means is selected from a group of resins consisting of unsaturated polyesters, bismaleimides, epoxy vinyl esters and epoxies.

15. The glass assembly of claim 13, wherein the liquid resin means includes an inorganic filler.

16. The glass assembly of claim 13, further comprising a reinforcing structure that is coupled to the rigid interlayer.

17. The glass assembly of claim 13, wherein the reinforcing structure includes a reinforcing member and a resin.

18. The glass assembly of claim 17, wherein the reinforcing member is a woven fiberglass.

19. The glass assembly of claim 17, further comprising a securing structure coupled to the reinforcing structure and adapted for use in mounting the glass structure.

20. The glass assembly of claim 13, wherein the glass structure includes a glass panel having a thickness of about 0.001 inch to about 0.4 inch.

21. A glass assembly comprising:

a glass structure with a front surface and a rear surface, the glass structure being deflected such that the front surface is axially contracted, which thereby places the front surface in a state of compression, and the rear surface is axially elongated, which thereby places the rear surface in a state of tension; and

a resin applied to the rear surface of the glass structure, the resin curing to form a rigid interlayer that inhibits the glass structure from returning to an undeflected state, the resin shrinking as it cures and applying an axially directed force to the rear surface that counteracts the axial elongation of the rear surface and places the rear surface in a state of compression.

22. The glass assembly of claim 21, wherein the resin is selected from a group of resins consisting of unsaturated polyesters, bismaleimides, epoxy vinyl esters and epoxies.

23. The glass assembly of claim 21, wherein the resin includes an inorganic filler.

24. The glass assembly of claim 21, further comprising a reinforcing structure that is coupled to the rigid interlayer.

25. The glass assembly of claim 24, wherein the reinforcing structure includes a reinforcing member and a resin.

26. The glass assembly of claim 25, wherein the reinforcing member is a woven fiberglass.

27. The glass assembly of claim 25, further comprising a securing structure coupled to the reinforcing structure and adapted for use in mounting the glass structure.

28. The glass assembly of claim 21, wherein the glass structure includes a glass panel having a thickness of about 0.001 inch to about 0.4 inch.

29. A glass assembly comprising:

a glass structure with a front surface and a rear surface, the glass structure being deflected such that the front surface is axially contracted, which thereby places the front surface in a state of compression, and the rear surface is axially elongated, which thereby places the rear surface in a state of tension; and

resin means bonded to the rear surface of the glass structure, the resin means forming a rigid interlayer that inhibits the glass structure from returning to an undeflected state, the resin means applying an axially directed compressive force to the rear surface of the glass structure that counteracts the axial elongation of the rear surface and places the rear surface in a state of compression.