US4368962A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solar tracking apparatus and system
Assignee: Individual
•
Filing: 1981-01-30
•
Granted: 1983-01-18
•
Expires: 2001-01-30
Abstract
Abstract A solar tracking apparatus and system for supporting and use with solar devices. The apparatus is comprised of a pair of concentric shafts oriented parallel to the earth's rotational axis with one shaft being rotated by a motor at one revolution per day, so that a yoke rigidly attached to this shaft will follow the diurnal motion of the sun. The second concentric shaft is rotated at a rate relative to the first shaft and by means of a spherical four-bar linkage will automatically produce a rotational oscillation of a support or gimbal mounted on the yoke equal to the yearly declination of the sun. A means is also provided for advancing or retarding the diurnal motion of the yoke at specific times of the year so as to correct for anomalies in the motion of the sun, commonly known as "the equation of time". A means is also provided for coupling a large array of solar tracking yokes to a single central drive unit.
Inventors
- 👤 Donald E. Hultberg
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 11:46
CPC Classifications
F; F24; F24S; F24S30/00; F24S30/40; F24S30/45; F24S30/458; F24S50/00; F24S50/20; F24S2030/10; F24S2030/13; F24S2030/136; Y; Y02; Y02E; Y02E10/00; Y02E10/40; Y02E10/47
Claims Analysis
Total Claims: 34
Claim 1
Independent Claim
197 words
An automatic solar tracking apparatus comprising: a first rotatable shaft means; mounting means mounting said first rotatable shaft means parallel to the axis of rotation of the earth; a yoke rigidly attached to said first shaft; first rotating means for providing open loop rotation to said first rotatable shaft means at a substantially uniform and continuous rate of one revolution per mean solar day; correcting means for correcting the rotational rate of said first rotatable shaft means an amount equal to the equation-of-time anomaly so as to accurately follow the hour-angle motion of the sun; support means mounted on said yoke rotatable about an axis perpendicular to the rotational axis of said first rotatable shaft means; a second rotatable shaft means; linking means linking said support means to said second rotatable shaft means; second rotating means adapted to provide open-loop rotation to said second rotatable shaft means at a substantially uniform and continuous rate of one revolution per siderial day so that differential rotational rates of said second shaft and said corrected first shaft cause said linking means to automatically oscillate said support means by an amount substantially equal to the yearly declination motion of the sun.
Claim 2
Dependent Claim
197 words
An automatic solar tracking apparatus comprising: a first rotatable shaft means; mounting means mounting said first rotatable shaft means parallel to the axis of rotation of the earth; a yoke rigidly attached to said first shaft; first rotating means for providing open loop rotation to said first rotatable shaft means at a substantially uniform and continuous rate of one revolution per mean solar day; correcting means for correcting the rotational rate of said first rotatable shaft means an amount equal to the equation-of-time anomaly so as to accurately follow the hour-angle motion of the sun; support means mounted on said yoke rotatable about an axis perpendicular to the rotational axis of said first rotatable shaft means; a second rotatable shaft means; linking means linking said support means to said second rotatable shaft means; second rotating means adapted to provide open-loop rotation to said second rotatable shaft means at a substantially uniform and continuous rate of one revolution per siderial day so that differential rotational rates of said second shaft and said corrected first shaft cause said linking means to automatically oscillate said support means by an amount substantially equal to the yearly declination motion of the sun.
Claim 3
Dependent Claim
45 words
The solar tracking apparatus according to claim 1 wherein said first rotating means comprises: a constant-speed motor; first coupling means connecting said motor to said first shaft, said first coupling means being proportioned to provide one revolution per mean solar day of said first shaft.
Claim 4
Dependent Claim
29 words
The solar tracking apparatus according to claim 2 wherein said first coupling means comprises: a plurality of gears coupling said motor to said first shaft for simultaneous rotation therewith.
Claim 5
Dependent Claim
40 words
The solar tracking apparatus according to claim 2 wherein said second rotating means comprises: a second coupling means coupling said motor to said second shaft whereby said second shaft makes one complete revolution per year relative to said first shaft.
Claim 6
Dependent Claim
39 words
The solar tracking apparatus according to claim 2 wherein said second rotating means comprises: a second coupling means coupling said motor to said second shaft whereby said support means makes one complete oscillation per year relative to said yoke.
Claim 7
Dependent Claim
42 words
The solar tracking apparatus according to claim 5 wherein said second coupling means provides a rotational rate of said second shaft relative to said first shaft substantially equal to the ratio of siderial days per year to the solar days per year.
Claim 8
Dependent Claim
30 words
The solar tracking apparatus according to claim 6 wherein said second coupling means comprises: a plurality of gears coupling said second shaft to said first shaft for simultaneous rotation therewith.
Claim 9
Dependent Claim
17 words
The solar tracking apparatus according to claim 1 wherein said linking means comprises a spherical four-bar linkage.
Claim 10
Dependent Claim
73 words
The solar tracking apparatus according to claim 8 wherein the spherical four-bar linkage comprises: a first arm having one end rigidly secured to said second shaft; a second arm rotatably secured to said first arm by means of a first pivot; a second pivot whose axis is perpendicular to the axis of said first pivot rotatably securing said second arm to said support means; all axes of rotation meeting at a common point.
Claim 11
Dependent Claim
23 words
The solar tracking apparatus according to claim 9 wherein said support means comprises a gimbal having its ends rotatably secured to said yoke.
Claim 12
Dependent Claim
18 words
The solar tracking apparatus according to claim 1 wherein said second shaft is concentric with said first shaft.
Claim 13
Dependent Claim
55 words
The solar tracking apparatus according to claim 11 wherein said correcting means comprises: correcting means for correcting errors due to the earth's orbit around the sun; said correcting means adapted to advance and retard the rotation of said yoke an amount equal to the eccentricity and obliquity error in the earth's motion around the sun.
Claim 14
Dependent Claim
87 words
The solar tracking apparatus according to claim 12 wherein said correcting means comprises: a lower main shaft and an upper main shaft comprising said first rotatable shaft means; said rotating means rotating said lower main shaft at one revolution per mean solar day; connecting means connecting said upper main shaft to said lower main shaft; and said connecting means adapted to rotate the upper main shaft relative to the lowermain shaft in a leading or lagging relationship according to anomalies in the earth's orbit around the sun.
Claim 15
Dependent Claim
57 words
The solar tracking apparatus according to claim 13 wherein said correcting means includes: a first arm secured to the lower main shaft; a second arm secured to the upper main shaft; a crank arm connecting said first and second arms whereby said upper main shaft rotates with said lower main shaft in a leading or lagging relationship.
Claim 16
Dependent Claim
41 words
The solar tracking apparatus according to claim 14 including: a gear train connecting said crank arm to said second shaft whereby said crank arm is rotated by the differential action of said second shaft with respect to said lower main shaft.
Claim 17
Dependent Claim
34 words
The solar tracking apparatus according to claim 15 wherein said gear train ratio is selected to rotate said crank at the differential rate of said second shaft with respect to said lower main shaft.
Claim 18
Dependent Claim
34 words
The solar tracking apparatus according to claim 15 wherein said gear train is selected to rotate said crank at twice the differential rate of said second shaft with respect to said lower main shaft.
Claim 19
Dependent Claim
107 words
The solar tracking apparatus according to claim 13 including: a first arm secured to the lower main shaft; a second arm secured to the upper main shaft; a third arm rotatably mounted between said first and second shaft; a first crank arm connecting said third arm to said second arm; and connecting means connecting said first and second crank arms whereby said upper main shaft is rotated in a leading or lagging relationship with respect to the lower main shaft whereby the sun tracker automatically compensates for anomalies due to the eccentricity of the earth's orbit around the sun and due to the obliquity of the ecliptic.
Claim 20
Dependent Claim
65 words
The solar tracking apparatus according to claim 18 wherein said connecting means comprises: a first gear train connecting said first crank arm to said second shaft; a second gear train connecting said second crank arm to said second shaft; and whereby said first and second crank arms are rotated simultaneously with said differential rotation of said second shaft with respect to said lower main shaft.
Claim 21
Dependent Claim
26 words
The solar tracking apparatus according to claim 19 wherein: said first gear train has a one-to-one ratio; and said second gear train has a two-to-one ratio.
Claim 22
Dependent Claim
67 words
The solar tracking apparatus according to claim 1 wherein: a said first rotating means comprises; a variable-speed motor; first coupling means coupling said variable-speed motor to said first shaft; said correcting means comprising a programmable speed-controlling means for adjusting the rotational rate of said variable-speed motor so as to rotate said first rotatable shaft at a rate substantially equal to the hour-angle rotational rate of the sun.
Claim 23
Dependent Claim
29 words
The solar tracking apparatus according to claim 21 wherein said first coupling means comprises: a plurality of gears coupling said motor to said first shaft for simultaneous rotation therewith.
Claim 24
Dependent Claim
87 words
The solar tracking apparatus according to claim 21 wherein said programmable speed-controlling means comprises: a computer program for repetitively solving an equation defining the hour-angle rotational rate of the sun as a function of time; a programmable clock-controlled computer means having a variable output which varies in proportion to said program; power transfer means driving said variable-speed motor in proportional response to the variable output of said computer means whereby said variable-speed motor will rotate said first rotatable shaft means at a rate defined by said equation.
Claim 25
Dependent Claim
48 words
The solar tracking apparatus according to claim 23 wherein said computer program is adapted to repetitively solve the following equation defining the hour-angle rotational rate of the sun, ω with respect to the earth as a function of time: ##EQU7## radians per day, wherein: ##EQU8## wherein: ##EQU9## wherein:
Claim 26
Dependent Claim
5 words
t=time (in days from perihelion)
Claim 27
Dependent Claim
5 words
t=time (in days from perihelion)
Claim 28
Dependent Claim
41 words
t o =time interval between perihelion and the vernal equinox (in days). ε=elliptical eccentricity of earth's orbit (0.01674). Δ=obliquity of the ecliptic (23.4523°). N=reduction ratio of said first coupling means. π=ratio of the circumference to the diameter of a circle (3.14159).
Claim 29
Dependent Claim
41 words
t o =time interval between perihelion and the vernal equinox (in days). ε=elliptical eccentricity of earth's orbit (0.01674). Δ=obliquity of the ecliptic (23.4523°). N=reduction ratio of said first coupling means. π=ratio of the circumference to the diameter of a circle (3.14159).
Claim 30
Dependent Claim
88 words
Solar tracking apparatus according to claim 1 wherein said second rotating means comprises: a constant-speed motor; a second coupling means coupling said constant-speed motor to said second shaft; said coupling means proportioned to provide a fixed rotational rate of one revolution per siderial day to said second shaft; said second coupling means orientated to provide the same directional rotational sense to said second shaft as said first shaft so as to yield a differential rotation substantially equal to one revolution per year between said first and second shafts.
Claim 31
Dependent Claim
30 words
The solar tracking apparatus according to claim 25 wherein said second coupling means comprises: a plurality of gears coupling said constant-speed motor to said second shaft for simultaneous rotation therewith.
Claim 32
Dependent Claim
28 words
The solar tracking apparatus according to claim 1 including: a pedestal mounting said solar tracking apparatus with the axis of said yoke parallel to the earth's rotational axis.
Claim 33
Dependent Claim
34 words
The solar tracking apparatus according to claim 27 including: a plurality of pedestals each having a solar tracking apparatus mounted thereon; and connecting means connecting said solar tracking systems to a central drive unit.
Claim 34
Dependent Claim
61 words
The solar tracking apparatus according to claim 28 wherein: said connecting means consists of a plurality of rotating drive shafts; said drive shafts extending outward from said central drive unit; said drive shafts branching geometrically by means of right-angle gear boxes; and said drive shafts terminating in 2 n trackers where n is the number of similar branches in the array.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-01-17 | 1986-07-19 | 1987-01-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-01-17 | 1990-07-19 | 1991-01-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-01-17 | 1994-07-19 | 1995-01-18 | $7700.00 | Window Closed / Lapsed |