Compliant hermetic seal system for flat glass panel assembly

1. A hermetically-sealed enclosure comprising:

at least two wall elements of substantially congruent shapes;

a spacer system defining an interior space between the wall elements; and

a bridge element including one or more flexible metal foil layers extending between adjacent, respective edges of the wall elements to isolate the interior space from a surrounding environment,

wherein the bridge element is substantially free of step discontinuities in total thickness along the intended weld path, and

wherein the bridge element is bonded to each of the wall elements via an ultrasonic weld to form a continuous bond line.

2. The enclosure of claim 1 , wherein the wall elements include glass.

3. The enclosure of claim 1 , wherein the bridge element includes a first foil layer and a second foil layer that is thicker than the first foil layer.

4. The enclosure of claim 3 , wherein the first foil layer is defined by two pieces of foil having a butt joint, and wherein the second foil layer overlays the butt joint.

5. The enclosure of claim 1 , wherein each foil layer is fabricated from a single sheet of foil.

6. The enclosure of claim 1 , wherein at least one foil layer includes separate pieces of foil that are hermetically bonded at a joint between the separate pieces of foil, and wherein the joint crosses the bond line.

7. The enclosure of claim 1 , wherein the bridge element is bonded via an ultrasonic weld that forms a plurality of bond lines, and wherein at least part of at least one bond line is defined by a plurality of ultrasonic weld segments overlapping at or near their adjacent ends.

8. The enclosure of claim 1 , wherein the bridge element is bonded via an ultrasonic weld that forms a plurality of bond lines, wherein at least part of at least one bond line has first and second ultrasonic weld segments that are adjacent and substantially parallel to each other, and wherein the second ultrasonic weld segment overlaps the first ultrasonic weld segment.

9. The enclosure of claim 1 , wherein at least one bond line is made to a coated surface of a wall element without removal of the coating from the bond line region.

10. The enclosure of claim 1 , wherein at least one bond line is made to a coated surface of a wall element, and wherein the coating has been removed in the region of the bond line by chemical edge deletion.

11. A method for manufacturing a hermetically-sealed enclosure, the method comprising:

assembling first and second wall elements of substantially congruent shapes together and separating the two wall elements from each other to form a space;

extending a bridge element between adjacent, respective edges of the wall elements, the bridge element including one or more layers of flexible metal foil, and the bridge element being substantially free of step discontinuities in total thickness;

bonding the bridge element to the first wall element by ultrasonic welding to form a continuous bond on the first wall element; and

bonding the bridge element to the second wall element by ultrasonic welding to form a continuous bond on the second wall element.

12. The method of claim 11 , further comprising bonding first and second foil layers to at least one of the first wall element and the second wall element.

13. The method of claim 12 , wherein each of the first and second layers is fabricated from a single sheet of foil.

14. The method of claim 12 , wherein the first foil layer is defined by two pieces of foil having a butt joint, and wherein the second foil layer overlays the butt joint.

15. The enclosure of claim 11 , wherein at least one foil layer includes separate pieces of foil that are hermetically bonded at a joint between the separate pieces of foil, and wherein at least one of the joints crosses the bond line.

16. The method of claim 11 , wherein at least one layer of the bridge element includes separate pieces that are hermetically bonded at joints, and wherein at least one of the joints crosses a bond line formed by bonding the bridge element to the first wall element, or a bond line formed by bonding the bridge element to the second wall element.

17. The method of claim 11 , further comprising forming a plurality of ultrasonic weld segments that overlap at least one of the bonds at or near their adjacent ends.

18. The method of claim 11 , wherein at least one bond formed by the bonding steps is made to a coated surface of a wall element without removal of the coating from the weld path region.

19. The method of claim 11 , wherein at least one bond formed by the bonding steps is made to a coated surface of a wall element, and wherein the coating has been removed in the region of the weld path by chemical edge deletion.

20. An insulated glazing unit comprising:

a first flat panel element;

a second flat panel element, the first and second flat panel elements having congruent shapes; and

a plurality of spacers disposed between the first flat panel element and the second flat panel element to space the first flat panel element from the second flat panel element; and

a bridge element including one or more flexible metal foil layers extending between adjacent, respective edges of first and second flat panel elements to isolate the interior space from a surrounding environment,

wherein the bridge element is substantially free of step discontinuities in total thickness along the intended weld path, and

wherein the bridge element is bonded to each of the wall elements via an ultrasonic weld to form a continuous bond line.