Stoves and furnaces – Solar heat collector – With means to convey fluent medium through collector
Reexamination Certificate
1999-06-09
2001-06-12
Lazarus, Ira S. (Department: 3743)
Stoves and furnaces
Solar heat collector
With means to convey fluent medium through collector
C126S653000, C126S674000, C126S570000, C126S572000, C126S585000
Reexamination Certificate
active
06244264
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention is an improved stationary collector of light that is especially adapted to collect sunlight. In particular, it is a non-imaging solar concentrator with reflecting sections that may be symmetric or asymmetric and with one or more absorbers.
Non-imaging passive solar collectors have been used for a number of years to gather and use sunlight at elevated temperatures. The term “passive” is taken to mean a collector that can receive and use solar energy at a wide range of angles so that it does not need to be moved to track the sun. Of course, such a collector could also be caused to move if desired.
An example of a non-imaging collector is given in U.S. Pat. No. 5,537,991 entitled “Non-imaging Solar Collector”, Winston et al., issued Jul. 23, 1996, which is incorporated here by reference as if set forth fully. The invention taught by that patent is a symmetric reflector with a central heat removal tube and a wedge-shaped absorber that extends from the absorber tube to or nearly to the symmetric reflector. The '991 patent has referred to the wedge-shaped absorber as exhibiting an “ice-cream-cone” geometry because its cross-section resembles an ice cream cone. The '991 patent overcomes some of the disadvantages of the prior art such as having radial fins that lose efficiency through re-radiation and also such as having non-concentrically disposed heat removal tubes. The '991 patent, however, has symmetric reflectors that place limits on their collection versatility over a range of angles of incidence of sunlight. It also has a wedge-shaped collector that extends from a central heat removal tube directly downward to the reflector. This also creates certain disadvantages in collection. The current state of the art is summarized in U.S. Pat. No. 5,586,013, entitled “Nonimaging Optical Illumination System,” U.S. Pat. No. 5,816,693, entitled “Nonimaging Optical Illumination System,” and U.S. Pat. No. 5,610,768, entitled “Nonimaging Radiant Energy Device.”
When solar collectors are used, the radiant flux that they concentrate can create problems if the heat is not removed from the region of the absorber. This may happen, for example, if a pump circulating a coolant through the collector fails. If steps are not taken quickly, the collector may be damaged or even destroyed.
It is an object of the present invention to make a better passive solar collector.
It is a further object of the present invention to provide a passive solar collector that will maximize collection of solar energy at times of day when the air-conditioning load is at or near a maximum.
It is a further object of the present invention to provide a passive solar collector that will absorb a maximum amount of solar radiation and reradiate a minimum amount.
It is a further object of the present invention to provide a passive solar collector that is protected against excessive temperatures without the need for human intervention.
It is a further object of the present invention to provide a solar collector that includes as an absorber a thermos-bottle configuration.
It is a further object of the invention to provide an improved method and apparatus for producing a user-selected non-imaging optical output from natural light sources.
It is a further object of the invention to provide a novel method and apparatus for providing user-selected non-imaging optical output of light energy from optical designs by controlling edge rays of a light source.
Other objects will become apparent in the course of a detailed description of the invention.
SUMMARY OF THE INVENTION
A passive solar collector has a reflector, a central tube and an absorber that is connected to the central tube. The absorber may be symmetric about some axis or it may be asymmetric. The central tube may be a type of thermos bottle that heats an enclosed fluid, or it may be a heat removal tube, or it may be part of a beat pipe, or it may contain a pipe that circulates fluid to be heated. Different reflectors may be optimized for particular times of the year so that there may be a winter collector and a summer collector, or collectors for even more different parts of the year. The reflector and the absorber may be enclosed in a transparent tube that normally contains air at a pressure less than atmospheric pressure, or a gas such as argon, xenon, or a gaseous compound having poor heat-transfer characteristics. The collector is protected against overheating by one or more of several systems, including a getter that releases gases to spoil the vacuum when it is overheated and reabsorbs the gases when it cools to restore the vacuum. The getter may be barium, zirconium, or a commercial getter material The collector may also be protected by a mechanically-operated shade that covers the collector if it overheats. The absorbent material may also be designed to reduce its absorption if it overheats, or the transparent tube may be treated with a material that darkens upon overheating to reduce the amount of light that is admitted.
REFERENCES:
patent: 2030350 (1936-02-01), Bremser
patent: 3823305 (1974-07-01), Schroder
patent: 3830288 (1974-08-01), Laing
patent: 3915147 (1975-10-01), Rineer
patent: 4056309 (1977-11-01), Harbison et al.
patent: 4059093 (1977-11-01), Knowles et al.
patent: 4112918 (1978-09-01), Palkes
patent: 4119085 (1978-10-01), Knowles et al.
patent: 4122831 (1978-10-01), Mahdjuri
patent: 4142509 (1979-03-01), Hermann et al.
patent: 4159712 (1979-07-01), Legg
patent: 4220139 (1980-09-01), Ramsden
patent: 4231353 (1980-11-01), Kanatani et al.
patent: 4290473 (1981-09-01), Pierson et al.
patent: 4307712 (1981-12-01), Tracy
patent: 4321419 (1982-03-01), Hanafin
patent: 4382436 (1983-05-01), Hager
patent: 4446850 (1984-05-01), Zilisch
patent: 4455998 (1984-06-01), Kroontje et al.
patent: 4494526 (1985-01-01), Wurst et al.
patent: 4531511 (1985-07-01), Hochberg
patent: 4579107 (1986-04-01), Deakin
patent: 4615329 (1986-10-01), Takeuchi et al.
patent: 4658806 (1987-04-01), Boozer
patent: 4766941 (1988-08-01), Sloop et al.
patent: 4834066 (1989-05-01), Collins et al.
patent: 5344206 (1994-09-01), Middleton
patent: 5625742 (1997-04-01), Boffito et al.
patent: 5735328 (1998-04-01), Salhoff et al.
patent: 26 22 718 (1977-12-01), None
patent: 2006420 (1979-05-01), None
patent: 57-174654 (1982-10-01), None
Foley & Lardner
Lazarus Ira S.
Lee David
Rechtin Michael D.
Solar Enterprises International, LLC
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