The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 20, 1998
Filed:
Jan. 16, 1996
John C Whitehead, Davis, CA (US);
Other;
Abstract
A variable volume of solar heated water is stored in an insulated indoor tank. The hot water is indirectly pressurized by incoming cold water, which is accumulated separately to maintain a constant total volume without mixing. A small reduction in the total pressure of hot water is maintained, so that water can flow through a solar heat collector and into hot storage without pumps. In one preferred embodiment, the incoming cold water is accumulated in a tank (8) located above an insulated hot water tank (14). The tanks share a volume of compressed air, which freely passes through a pipe (12) connected between the tops of the two tanks. The transfer of compressed air permits incoming cold water to pressurize and displace hot water without mixing or heat loss. A control valve (24) is opened during sunny hours to permit flow from the upper tank (8), through a solar heat receiver (30), and into the lower tank (14). This collector flow is driven by the reduced elevation pressure of water in the lower tank (14), so no pump is needed. The valve controller (44) is simple because there is no possibility of sending heated water to a cooler collector, and flow stops by itself when the hot tank (14) becomes full. The air pipe (12) additionally serves as a bypass to deliver cold water after all hot water is used. Means are provided for freeze protection, replacement of lost air, and venting of excess air. The collector (30) may be located on the roof of a building, while the tanks (8, 14) are located lower in the building.