US3678685A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solar energy powered heliotrope
Assignee: National Aeronautics and Space Administration
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Filing: 1970-09-25
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Granted: 1972-07-25
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Expires: 1990-09-25
Abstract
Abstract This invention relates to a solar energy powered heliotrope which functions in a passive, stored energy manner to orient a solar array towards the sun. A bimetallic motor element is activated by solar energy to generate a work output. A constant torque spring assembly coupled to the motor element stores useful energy as a function of the work output. A bimetallic sensing element detects misorientation between the solar array and the sun. An escapement mechanism is actuated by the sensing element whenever misorientation between the solar array and the sun is detected; the escapement mechanism automatically and incrementally releases the stored energy to rotate the solar array in discrete increments until it is oriented towards the sun.
Inventors
- 👤 Ralph Crawford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:29
CPC Classifications
F; F24; F24S; F24S50/00; F24S50/20; F03; F03G; F03G6/00; F03G6/002; Y; Y02; Y02E; Y02E10/00; Y02E10/40; Y02E10/46; Y02E10/47
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
76 words
A solar energy powered heliotrope for orienting a solar array towards the sun comprising motor means responsive to solar energy for generating a work output; energy storage means coupled to said motor means for storing energy as a function of said work output; sensing means for detecting misorientation between said solar array and the sun; and means actuated by said sensing means for stepwise releasing energy stored by said storage means to drive said solar array.
Claim 2
Dependent Claim
76 words
A solar energy powered heliotrope for orienting a solar array towards the sun comprising motor means responsive to solar energy for generating a work output; energy storage means coupled to said motor means for storing energy as a function of said work output; sensing means for detecting misorientation between said solar array and the sun; and means actuated by said sensing means for stepwise releasing energy stored by said storage means to drive said solar array.
Claim 3
Dependent Claim
17 words
The heliotrope of claim 1 wherein said means actuated by said sensing means is an escapement means.
Claim 4
Dependent Claim
16 words
The heliotrope of claim 1 wherein said motor means and said sensing means comprise bimetallic elements.
Claim 5
Dependent Claim
13 words
The heliotrope of claim 3 wherein said bimetallic elements comprise helically shaped coils.
Claim 6
Dependent Claim
16 words
The heliotrope of claim 3 wherein said energy storage means comprises a constant torque spring assembly.
Claim 7
Dependent Claim
90 words
A solar energy powered heliotrope for orienting a solar array towards the sun comprising thermal motor means responsive to solar energy for generating a work output; energy storage means receiving said work output for storing useful energy as a function of said work output; thermal sensing means for detecting misorientation between said solar array and the sun; and escapement means actuated by said thermal sensing means for releasing energy stored by said storage means to drive said solar array and thereby produce orientation of said solar array towards the sun.
Claim 8
Dependent Claim
90 words
A solar energy powered heliotrope for orienting a solar array towards the sun comprising thermal motor means responsive to solar energy for generating a work output; energy storage means receiving said work output for storing useful energy as a function of said work output; thermal sensing means for detecting misorientation between said solar array and the sun; and escapement means actuated by said thermal sensing means for releasing energy stored by said storage means to drive said solar array and thereby produce orientation of said solar array towards the sun.
Claim 9
Dependent Claim
19 words
The heliotrope of claim 6 wherein said thermal motor means and said thermal sensing means comprise bimetallic helical coils.
Claim 10
Dependent Claim
24 words
The heliotrope of claim 7 wherein said energy storage means comprises a constant torque spring assembly wherein said energy is stored in tensioned springs.
Claim 11
Dependent Claim
58 words
The heLiotrope of claim 8 wherein said thermal sensing means further comprises shade means for alternately causing solar illumination and shadowing of said thermal sensing means whereby said escapement means is actuated by said thermal sensing means to release said energy stored by said storage means in discrete increments each time said sensing means is illuminated or shadowed.
Claim 12
Dependent Claim
74 words
The heliotrope of claim 9 wherein said shade means comprises an inner cylindrical shade fixedly positioned to completely surround said thermal sensing means, and an outer cylindrical shade concentric and rotatable with respect to said inner shade, both said inner and outer shades having a plurality of alignable slots therein whereby said thermal sensing means is illuminated when said plurality of slots are aligned and is shadowed when said plurality of slots are misaligned.
Claim 13
Dependent Claim
73 words
The heliotrope of claim 10 wherein said outer cylindrical shade is rotated by each release of said energy stored by said storage means, and said inner and outer shades are synchronized with said escapement means whereby whenever one increment of energy is released so that said outer shade rotates to misalign said slots, an immediately succeeding release of said energy stored by said storage means rotates said outer shade to align said slots.
Claim 14
Dependent Claim
44 words
The heliotrope of claim 11 wherein said outer shade further comprises a solid arc section on a surface of said outer shade, said solid arc section being capable of shadowing said thermal sensing means when said solid arc section is normal to the sun.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-07-25 | 1976-01-24 | 1976-07-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-07-25 | 1980-01-24 | 1980-07-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-07-25 | 1984-01-24 | 1984-07-25 | $7700.00 | Window Closed / Lapsed |