Vacuum insulation panel

• US 20050144904A1
• Filed: 11/19/2004
• Published: 07/07/2005
• Est. Priority Date: 11/19/2003
• Status: Active Grant

• Current Assignee: Level Holding B.V.
• Original Assignee: Level Holding B.V.
• Inventors: Veltkamp, Wessel Bart
• Granted Patent: US 8,137,784 B2
• Time in Patent Office: Days
• US Class Current: 52/782.100
• CPC Class Codes: E04B 1/803 with vacuum spaces included in the slab
• CPC Class Codes: Y02A 30/242 Slab shaped vacuum insulation
• CPC Class Codes: Y02B 80/10 Insulation, e.g. vacuum or aerogel insulation
• CPC Class Codes: Y10T 428/24 Structurally defined web or sheet [e.g., overall dimension, etc.]

Abstract

The invention relates to a thermal insulation panel, comprising: a housing with: a first main wall and a second main wall which each extend perpendicularly of a temperature gradient, and auxiliary walls connecting both main walls and extending parallel to the temperature gradient, wherein the auxiliary walls connect with ribs to the main walls, and a filling placed in the housing and able to withstand pressure forces, wherein the pressure within the housing is reduced to a value at which no heat transfer of any significance takes place, and wherein the housing is manufactured from metal, wherein a strip of the auxiliary wall contacting a rib is welded to the main wall, and that a welding strip is welded onto the weld. With mere welding of a sufficiently thin metal foil it is practically impossible to obtain a weld of sufficient quality. With a sandwich weld it is possible to obtain a sufficiently strong and reliable welded connection, even when a very tin metal foil is used as auxiliary wall.

Claims

1. Thermal insulation panel, comprising:

a housing with;

a first main wall and a second main wall which each extend perpendicularly of a temperature gradient, and

auxiliary walls connecting both main walls and extending parallel to the temperature gradient, wherein the auxiliary walls connect with ribs to the main walls, and

a filling placed in the housing and able to withstand pressure forces,

wherein the pressure within the housing is reduced to a value at which no heat transfer of any significance takes place, and

wherein the housing is manufactured from metal,

characterized in that a strip of the auxiliary wall contacting a rib is welded to the main wall, and that a welding strip is welded onto the weld.

2. Thermal insulation panel as claimed in claim 1, characterized in that the auxiliary walls are formed by a piece of metal foil with a thickness between 10 and 50 μ

m.

3. Thermal insulation panel as claimed in claim 2, characterized in that the metal foil is formed by foil of stainless steel.

4. Thermal insulation panel as claimed in claim 1, characterized in that the material of the welding strip is the same as the material of the main wall.

5. Thermal insulation panel as claimed in claim 1, characterized in that the filling material is formed by an open-cell material with small cavities.

6. Thermal insulation panel as claimed in claim 5, characterized in that the filling material is provided with evacuation channels on at least a surface extending transversely of the direction of the temperature gradient.

7. Thermal insulation panel as claimed in claim 6, characterized in that the evacuation channels are arranged in a body separated from the rest of the filling.

8. Thermal insulation panel as claimed in claim 1, characterized in that the filling material comprises fibers extending substantially parallel to the main walls.

9. Thermal insulation panel as claimed in claim 1, characterized in that at least one fixing bracket is attached by means of welding to at least one of the main walls.

10. Thermal insulation panel as claimed in claim 1, characterized in that the housing takes the form of a block and that the main walls are flat.

11. Thermal insulation panel as claimed in claim 9, characterized in that the main walls are bent at their edges in order to form a skirt, which is welded to the auxiliary walls.

12. Thermal insulation panel as claimed in claim 11, characterized in that the skirt is deep-drawn to a thinner dimension.

13. Thermal insulation panel all claimed in claim 9, characterized in that a skirt is formed on the main walls by an angle profile connected to the main wall by welding.

14. Thermal insulation panel as claimed in claim 13, characterized in that the main walls extend outside the auxiliary walls and that the angle profile is welded to the part of the main wall protruding outside the auxiliary wall.

15. Thermal insulation panel as claimed in claim 8, characterized in that the auxiliary walls comprise rounded corners.

16. Thermal insulation panel, characterized in that

the thermal insulation panel is formed from a number of insulation panels as claimed in claim 10, placed with the main surfaces onto each other, and

the mutually adjacent main walls are combined into a single intermediate wall.

17. Thermal insulation panel as claimed in claim 16, characterized in that the intermediate wall is reduced to a wall extending between the auxiliary walls.

18. Thermal insulation panel as claimed in claim 1, characterized in that the insulation panel has the form of the jacket of a circular cylinder that the temperature gradient extends radially and that the main surfaces are placed concentrically.

19. Thermal insulation panel as claimed in claim 18, characterized in that the auxiliary walls are annular and that an outward extending skirt is formed by bending on the outer edge and the inner edge, which skirt is welded to the main walls.

20. Thermal insulation panel as claimed in claim 19, characterized in that the skirts of the auxiliary walls are welded against the inner surfaces of the main walls.

21. Thermal insulation panel as claimed in claim 18, characterized in that the filling material is formed by winding a fiber helically round the inner main wall.

22. Thermal insulation panel as claimed in claim 8, characterized in that the fibers are formed by glass fibers.

23. Box-like construction open on one side, characterized in that the walls of this box-like construction are assembled from panels as claimed in claim 10, wherein the main walls are situated on the inner side respectively the outer side of the box-like construction.

24. Box-like construction as claimed in claim 23, characterized in that mutually connecting main surfaces of the panels are connected only to each other.

25. Box-like construction as claimed in claim 23, characterized in that main surfaces adjacent to the open side are provided with a strip of foil connecting to the open side.

38. Method as claimed in claim 25, characterized in that the evacuation is carried out via an opening which is arranged in a main wall and which is closed after evacuation by welding on a plate, which during evacuation is held in place above the opening by means of magnetism.

39. Method as claimed in claim 38, characterized in that the beginning of the evacuation is carried out at a vacuum pump pressure which results in laminar flow in the evacuation channels and molecular flow in the filling.

40. Method as claimed in claim 38, characterized in that flushing takes place up to a pressure wherein laminar flow just occurs in the filling.

41. Method as claimed in claim 38, characterized in that flushing takes place with a light gas during evacuation.

26. Method for manufacturing a thermal insulation panel, comprising:

a housing with;

a first main wall and a second main wall which each extend perpendicularly of a temperature gradient, and

auxiliary walls connecting both main walls and extending parallel to the temperature gradient, wherein the auxiliary walls connect with ribs to the main walls, and

a filling placed in the housing and able to withstand pressure forces,

wherein the pressure within the housing is reduced to a value at which no heat transfer of any significance takes place,

wherein the housing takes the form of a block and the main walls are flat; and

wherein the housing is manufactured from metal,

characterized by the following steps of;

placing on each other a lower main wall, the filling and the upper wall;

arranging a foil, from which the auxiliary wall must be formed, around the thus formed assembly;

welding the foil to the skirts; and

evacuating the thus resulting panel,

wherein the foil is welded to the skirts while adding a welding strip.

27. Method as claimed in claim 26, characterized in that the foil is welded simultaneously to both the skirts adjacent to the foil.

28. Method as claimed in claim 27, characterized in that the welding takes place by means of laser welding.

29. Method as claimed in claim 26, characterized in that the foil is pulled tight before welding commences.

30. Method as claimed in claim 26, characterized in that the loose end of the foil is pulled tight during the welding.

31. Method as claimed in claim 26, characterized in that the lower main wall is placed on a vacuum table prior to welding.

32. Method as claimed in claim 31 characterized in that an underpressure is applied to the interior of the panel during welding.

33. Method as claimed in claim 32 characterized in that an auxiliary foil is placed around the assembly while an under pressure is being applied and that the metal foil and the welding strips are arranged simultaneously with the welding while the auxiliary foil is removed.

34. Method for manufacturing a thermal insulation panel as claimed in claim 26, characterized in that prior to placing of the filling, the filling is formed by winding a fiber around a core, cutting through the thus formed fiber package in radial-axial direction to the winding core.

35. Method as claimed in claim 34, characterized in that during winding the tension in the fiber is controlled for the purpose of winding the fiber with a tension such that the tension in the fibers is substantially the same at cutting.

36. Method as claimed in claim 35, characterized in that the tension in the fibers is controlled by subjecting the fibers to an increase in temperature.

42. Method as claimed in claim 36, characterized in that the opening is closed after evacuation, and the pressure is measured after a certain period of time, wherein the panel is rejected if the pressure is too high.

37. Method for manufacturing a thermal insulation panel, comprising:

a housing with;

a first main wall and a second main wall which each end perpendicularly of a temperature gradient, and

auxiliary walls connecting both main walls and extending parallel to the temperature gradient, wherein the auxiliary walls connect with ribs to the main walls. and

a filling placed in the housing and able to withstand pressure forces,

wherein the pressure within the housing is reduced to a value at which no heat transfer of any significance takes place.

wherein the parts of the auxiliary walls connecting onto the ribs are thicker than the remaining part of the auxiliary walls,

wherein the housing takes the form of a cylinder; and

wherein the housing is manufactured from metal,

characterized by the following steps of;

winding a filling round the inner main wall;

arranging the outer main wall around the filling;

placing the auxiliary walls against the main walls;

welding bent edges of the auxiliary walls to the main walls while adding a welding strip; and

evacuating the thus resulting panel,

wherein the foil is welded to the skirts while adding a welding strip.