| 摘要 |
A vacuum insulated panel having high thermal insulating value and long vacuum life, and a method of making such a panel is disclosed. The panel is formed of peripherally welded metal wall members (212, 214) which define a cavity within which a compressed block (222b) of particulate material is disposed. The particulate material, preferably activated carbon, silica or a combination thereof, serves as a barrier to radiant thermal transmission through the panel, acts as a getter to maintain the vacuum in the cavity, and supports the walls of the panel against collapse when the cavity is evacuated. The vacuum insulated panel can be covered with a polyurethane foam insulating material. In one embodiment, the vacuum insulated panel can include a compressed cake of particulate material, e.g., activated carbon, together with an upper layer of fiberglass batt. These two materials form the center of a metal panel sandwich, with the activated carbon serving as a barrier to radiant thermal transmission through the panel, and as a getter, and with the fiberglass batting (222a) serving to filter the particulate material to prevent it from leaving the panel when the panel is placed under a vacuum, for wiping the sidewalls of one of the panels when the panels are assembled, and for preventing the compressed particulate material from entering the peripheral area of the panels which ar welded together to form a complete panel. In a further embodiment of the invention, the cake within the cavity is a sandwich comprising a layer of compressed activated carbon (222b) positioned between two layers (222a, 222c) of compressed fiberglass. |
