Solar energy concentration system

• US 4,266,179 A
• Filed: 02/27/1979
• Issued: 05/05/1981
• Est. Priority Date: 02/27/1979
• Status: Expired due to Term

• Current Assignee: Solar Powered Generators Limited
• Original Assignee: James E. Hamm Jr
• Inventors: Hamm, James E. Jr.
• Primary Examiner(s): HICKEY, ROBERT
• Application Number:
  US06/015,858
• Time in Patent Office: 798 Days
• Field of Search: 322/2 R, 310/306, 353/3, 250/203 R, 126/424, 126/425, 136/89 PC, 350/289, 350/292-294
• US Class Current: 322/2.00R
• CPC Class Codes: F24S 23/79 with spaced and opposed interacting reflective surfaces
• CPC Class Codes: F24S 23/80 having discontinuous faces
• CPC Class Codes: F24S 30/425 Horizontal axis
• CPC Class Codes: F24S 50/20 for tracking
• CPC Class Codes: Y02E 10/47 Mountings or tracking

Abstract

A solar radiant energy concentrating system for concentrating solar radiation on a radiant to electric power thermionic conversion transducer. The radiated energy concentration system utilizes multiple reflector units that collectively together or selectively less than all reflectors as an intensity control are settable to reflect solar radiation onto a multi-surfaced concentrator down onto a focal area encompassing the target area for reflection from the concentrator to the transducer input. The energy concentration is varied in the ratio range of from 20,000 to 1 up to 250,000 to 1. Reflector units are set to compensate for the constantly varying declination angle of the earth toward the sun, step tracks the sun compensating for daily rotation of the earth West to East on its axis up to a full 360° depending on latitude North or South of the equator. The concentrator is generally circular in shape, made up of a series of circular bands with the concentrator stationary and situted such that one or more of the reflector devices can be appropriately aligned at all times to reflect the desired greatest amount of solar energy onto the concentrator. The circular bands are concaved inward and each set at an angle in reference to a flat-face surface to reflect and concentrate the solar rays'"'"' input between the inner and outer edges of a circular band to a prescribed facal area. The transducer is also mounted in stationary relation to the concentrator such as to avoid flexing of electrical power leads.

Claims

1. In a solar radiant energy concentration system:

a reflective concentrator;

a thermionic energy conversion transducer;

said concentrator and said transducer being mounted in fixed relation to each other;

reflector means positioned for reflecting solar radiation to said concentrator and focusing of solar radiation from said concentrator to said transducer;

position setting means;

tracking means for reflector means tracking of the sun during daylight hours of the day;

wherein said reflector means is a plurality of reflectors each positioned for reflecting solar radiation to said concentrator; and

at least one reflector of said plurality of reflectors mounted on each of a plurality of declination adjustor support platforms;

said position setting means includes a one-time declination-latitude position setting structure for each of said declination adjustor support platforms;

each said position setting structure includes declination adjustor support means set at an inclination angle compensating for the latitude of the system location;

said concentrator and said transducer are mounted in substantially North-South orientation with said concentrator generally closer to the equator than said transducer;

said declination adjustor support means is in the form of a platform with pivotal interconnect means at one end with mounting means and having inclination angle setting means supporting said platform at a declination angle with declination angle setting lock means;

with positioning of said declination adjustor means in substantially a North-South orientation at site location with said platform interconnect means at the end of said platform being located toward the equator;

a declination adjustment device is mounted on each of said declination adjustor support platforms;

said declination adjustment device is constructed with the declination adjustment range of 47 degrees movement corresponding to the yearly relationship of the earth to sun North-South-North rotation movement of 47 degrees to eliminate the offset caused by the declination angle of the earth'"'"'s axis; and

wherein said declination adjustment device includes a pivotally mounted declination swivel platform;

an arc segment gear fixed to said declination swivel platform;

a gear rack bar in drive engagement with said arc segment gear and mounted for slidable longitudinal back and forth guided movement on each said declination adjustor support platform;

a drive wheel interconnected by connecting rod means with said gear rack bar for drive of said gear rack bar in a sine wave type plot; and

step drive means for said drive wheel.

2. The solar radiant energy concentration system of claim 1, wherein said reflective concentrator is generally circular in shape made up of a plurality of circular bands.

3. The solar radiant energy concentration system of claim 2, wherein said plurality of circular bands are concaved inward with any one transverse section of each band at any annular location thereon set at an angle relative to a flat-face reference surface of said reflective concentrator.

4. The solar radiant energy concentration system of claim 1, wherein said transducer is a thermionic conversion transducer having relatively closely spaced cathode emitter disc and anode collector disc;

with said anode collector disc having a rearwardly extending cooling extension body; and

with the transverse area of said cathode emitter disc and the anode collector disc substantially enlarged relative to the transverse dimension of said cooling extension body to present adequate focal target area at the transducer cathode emitter disc input target surface.

5. The solar radiant energy concentration system of claim 4, wherein space between said cathode emitter disc and said anode collector disc is less than approximately 0.04 of an inch.

6. The solar radiant energy concentration system of claim 1, wherein each reflector is a flat plate reflector.

7. The solar radiant energy concentration system of claim 1, wherein some of the reflectors of said plurality of reflectors are slightly curved concave reflectors providing some focusing of reflected solar radiation to said concentrator.

8. The solar radiant energy concentration system of claim 7, wherein said concave reflectors are larger in lateral expanse than said concentrator.

9. The solar radiant energy concentration system of claim 1, wherein said drive wheel is a circumferentially toothed wheel with 365 teeth, one for each day of the year, driven by once a day activated step drive means;

and computer digital clock drive signal source means for activating said once a day activated step drive means.

10. The solar radiant energy concentration system of claim 9, wherein said once a day activated step drive means is a solenoid drive device drive engaging teeth of said drive wheel;

and solenoid activated drive wheel position lock and unlock means.

11. The solar radiant energy concentration system of claim 1, wherein each said pivotally mounted declination swivel platform mounts daily rotation adjustor means for tracking daily movement of the sun with reflector means mounted thereon;

and at least one reflector as said reflector means mounted on each said pivotally mounted declination swivel platform.

12. The solar radiant energy concentration system of claim 11, wherein mounting structure for reflector means on each said pivotally mounted declination swivel platform includes, a support post;

and a reflector mounting shaft rotatably mounted in said support post to extend horizontally transversely relative to said declination swivel platform; and

daily rotation drive means mounted on said declination swivel platform;

gear means driven by said daily rotation drive means interconnected to drive said reflector mounting shaft in rotary motion tracking the sun.

13. The solar radiant energy concentration system of claim 12, wherein said daily rotation drive means includes a stepping solenoid drive engaging said gear means;

and computer system digital pulse drive circuit means circuit connected to said stepping solenoid.

14. The solar radiant energy concentration system of claim 12, wherein lock and unlock means is provided position locking and unlocking said gear means driven by said daily rotation drive means;

said gear means having daily start position indexing means; and

reset means for returning said gear means back to the daily start index position.

15. The solar radiant energy concentration system of claim 14, wherein said reset means includes spring return means interconnecting said gear means and fixed means on said pivotally mounted declination swivel platform with said spring return means resiliently stressed to return said gear means and the reflector means positioned thereby back to the daily start index position when the daily rotation drive stepping solenoid is disengaged and when said lock and unlock means is in the unlocked state from said gear means.

16. The solar radiant energy concentration system of claim 15, wherein reset switch means mounted on said declination swivel platform is positioned for activation by said drive wheel in a daily driven limit position;

projection means on said drive wheel for contacting said reset switch means in the daily driven limit position; and

circuit connection of said reset switch means for time computer activation and deactivation of said daily rotation drive stepping solenoid and said lock and unlock means for reset return of said gear means and the reflector means positioned thereby back to the daily start index position.

17. The solar radiant energy concentration system of claim 14, wherein said gear means includes a first bevel gear mounted on and rotatable with said drive wheel;

and a second bevel gear mounted on and rotatable with said reflector mounting shaft in driven engagement with said first bevel gear.

18. The solar radiant energy concentration system of claim 14, including focused radiant energy intensity control means connected for sensing temperature of transducer means components through current flow sensing;

said focused radiant energy intensity control means also connected to computer time control means of the system for selective reset return of one or more of said gear means and reflector means set combinations.