초록 ▼

The wall of a protective jacket of a vacuum flask, containing a double-walled vessel whose walls are permeable to solar radiation, includes parts capable of being swung open. These parts and a wall part situated between them each have a reflective coating. The reflective surfaces of these coatings,

The wall of a protective jacket of a vacuum flask, containing a double-walled vessel whose walls are permeable to solar radiation, includes parts capable of being swung open. These parts and a wall part situated between them each have a reflective coating. The reflective surfaces of these coatings, viewed in cross-section, extend along a parabola when the movable wall parts are opened out, so that incident solar radiation is collected in the core zone of the vessel. A solar-radiation absorbing member may be disposed in this core zone, e.g., a metal tube having a black outer surface. Liquid contents of such a vacuum flask can be heated by means of solar energy.

대표청구항 ▼

In a vacuum flask of the type including a vessel having an inner wall and an outer wall, both permeable to solar radiation and bounding a space exhausted of air, and a protective jacket, the improvement which comprises: a said protective jacket of which at least one part is capable of being open, sa

In a vacuum flask of the type including a vessel having an inner wall and an outer wall, both permeable to solar radiation and bounding a space exhausted of air, and a protective jacket, the improvement which comprises: a said protective jacket of which at least one part is capable of being open, said part having an inner surface with reflective means to deflect solar radiation to said vessel to heat the contents thereof when said part is swung open.