| 20090194250 | HEAT ACCUMULATOR - A heat accumulator includes a thermally insulated heat storage vessel having an opening formed in a bottom wall thereof, a quantity of heat accumulating medium arranged within the vessel, and a fluid circulation tube of double tube structure inserted from the opening into the vessel and extending vertically upward toward a top wall of the vessel for introducing a fluid into the vessel or discharging the fluid out of the vessel. The heat accumulator further includes a heat-insulating layer provided on an outer peripheral surface of the fluid circulation tube and extending over at least a longitudinal portion of the fluid circulation tube extending from the bottom wall of the vessel in an upward direction to a predetermined height of the vessel. | 08-06-2009 |
