Apparatus and method for bending glass using microwaves

• US 20070000285A1
• Filed: 09/07/2006
• Published: 01/04/2007
• Est. Priority Date: 06/28/2002
• Status: Abandoned Application

• Current Assignee: Guardian Glass LLC (KOCH Industries Incorporated)
• Original Assignee: Guardian Industries Corporation (KOCH Industries Incorporated)
• Inventors: Vandal, Robert
• Application Number:
  US11/516,647
• Publication Number:
  US 20070000285A1
• Time in Patent Office: Days
• US Class Current: 65/287
• CPC Class Codes: B32B 17/10036 comprising two outer glass sheets
• CPC Class Codes: B32B 17/10174 Coatings of a metallic or dielectric material on a constituent layer of glass or polymer
• CPC Class Codes: B32B 17/10761 containing vinyl acetal
• CPC Class Codes: B32B 17/10889 shaping the sheets, e.g. by using a mould B32B17/10816 takes precedence
• CPC Class Codes: C03B 29/00 Reheating glass products for softening or fusing their surfaces; Fire-polishing; Fusing of margins
• CPC Class Codes: C03B 29/025 Glass sheets
• CPC Class Codes: C03C 23/0065 by microwave radiation
• CPC Class Codes: Y02P 40/57 Improving the yield, e-g- reduction of reject rates

Abstract

5 An apparatus and method for bending glass substrate(s) are provided. Microwave radiation is used to heat glass substrate(s) for bending. As a result, a coating supported by the substrate(s) is not heated as much during the bending process compared to if only conventional IR radiation was used. Thus, more extreme degrees of glass bending may be achieved, and/or the likelihood of coating damage reduced.

Claims

1. An apparatus for bending coated glass, the apparatus comprising:

at least one source for directing microwave radiation toward a glass substrate in order to heat the glass substrate for bending, wherein a coating supported by the glass substrate comprises at least one infrared (IR) reflecting layer comprising silver (Ag) sandwiched between at least a pair of dielectric layers; and

means for bending the heated glass substrate and the coating thereon so that a smallest radius of curvature defined by a major surface of the resulting bent glass substrate is no greater than about 3,000 mm.

2. The apparatus of claim 1, wherein the glass substrate is bent so that the smallest radius of curvature defined by the bent glass substrate is no greater than about 2,000 mm.

3. The apparatus of claim 1, wherein the glass substrate is bent so that the smallest radius of curvature defined by the bent glass substrate is no greater than about 1,000 mm.

4. The apparatus of claim 1, wherein the microwave radiation comprises wavelength(s) within a range of from about 6 to 10 mm.

5. The apparatus of claim 1, wherein the microwave radiation consists essentially of wavelength(s) within a range of from about 6 to 10 mm.

6. The apparatus of claim 1, wherein the coating comprises first and second IR reflecting layers each comprising Ag, and at least one dielectric layer provided between the first and second IR reflecting layers.

19. The apparatus of claim 1, further comprising an IR radiation source for pre-heating at least one of the glass substrates to about 400 to 550 degrees C., and thereafter using the microwave energy to increase the temperature of the glass substrate(s) to bending temperature(s).

7-18. -18. (canceled)

20. (canceled)