Note: Descriptions are shown in the official language in which they were submitted.
1~13~3
This invention relates to a solar energy concentra-
ting and collecting arrangement, and more particularly to such an
arrangement having a movable collector which is moved to various
positions for maximizing of the collected solar energy as a
function of the solar angle throughout the year and during each
day.
Various solar energy collection arrangements are known.
Many utilize a parabolic mirror or mirrors with a collector
located at the focus. These rnirrors and collectors convention-
ally move as a unit for pointing at the sun.
Several other prior arrangements employ a stationarymirror or mirrors with a movable collector or collectors. Among
these are a spherical mirror construction with a movable cen-
trally spaced collector arranged to angularly move about a
fulcrum according to the position of the sun and the season of
the year. The spherical mirror employs a complex curvature which
- is difficult, expensive, and impractical for large manufacture.
A second arrangement as shown in German Patent 517,417, issued
February 4, 1931, uses an oblong laterally symmetrical parabolic
mirror with its horizontal focus line directly vertically above
the center of and symmetrical with the oblong parabolic re-
flector. To accommodate small variations in sun angle away from
the vertical, the collector is moved both laterally and ver-
tically through a pivoted telescoping arm and cam guideway
; arrangement. The compass orientation of this system is not clear
in view of various inconsistencies in the description. However,
in any event it appears that as a practical matter very little
angular movement of the sun away from the vertical (as viewed ~ ~;
from the end of the reflector and collector) can be accommodated
30 with this system, and certainly not the extent of annual change ~-
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of sun angle relative to the horizontal. In addition the system
is relatively complex and to a considerable extent unwieldy
on a large scale in view of the guide cam and telescoping arm
requirements. It appears that to utilize this arrangement
over any extended period of days or seasons, and even during
large changes of sun angle during some days of the year, the
reflector would also require some form of rocking or pivoted
reorientation to vary the angular position of the mirror, in
addition to utilizing the cam and telescoping collector-support
arm arrangement.
It is an object and feature of the present invention
to provide a relatively simple solar energy concentrating and
collection arrangement which enables the employment of a fixed
reflector and simply movable collector while providing for
practical year-round utili~ation during the major insolation
., .
periods in each day of the year.
The present invention provides a solar energy concen-
trating and collecting arrangement, comprising a generally
~ upwardly facing concave refle¢tor fixedly positioned during
; 20 operational reflection, and a collector havlng a longitudinal
extent extending along the length of the reflector, the collector
being disposed in parallel spaced relation from the effective
reflecting surface of the reflector and movable across a portion
of the arcuate width of the reflector, the reflector having
a first concave radius of curvature along the effectlve length
of a first cyllndrical concentrating reflective arc segment
, thereof, and a second and third lesser concave radii of curva-
ture along the effective length of second and third concentra-
ting reflective cylindrlcal arc segments thereof, each of the
radii lying on a respective axls line running along the length
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of the reflector, the first larger radius cylindrical concentra-
ting reflective arc segment lying between said second and third
:- lesser radii arc segments, and each of the lesser radii cylin~
drical arc segments being inclined at a lesser angle to the
vertical than the first concave concentrating larger radius
reflective arc segment, and means for moving the collector . :
laterally above the reflectQr across a portion of the arcuate ~.
width of the collector to maintain the collector within a beam
of solar energy reflected by the reflector as the reflected
beam moves across the lateral width of the reflector as a function
of variation of the sun angle.
The invention will become more readily apparent to
those skilled in the art from a reading of the following detailed
description of a physical embodiment and mode of practice of the :.
invention, taken in conjunction with the accompanying drawings,
wherein:
Figure 1 is a schematic view of a building, such as -~
; a house, factory, school, etc., embodying the invention;
Figure 2 is a perspec.tive view of a portion of the
roof/reflector-concentrator8 and collectors of the embodiment
of Figure 1, illustrating the general layout;
Figure 3 is an enlarged fragmentary view, illustrating .~ :
in more detail the collector support and movement-imparting . .
arrangement;
Figure 3A i5 a further enlarged cross-sectional view
~ of the collector;
j.: Figure 4 illustrates a modified collector support arm
connecting arrangement;
Figure 5 (which appears on the same sheet as Figure 1)
30 illustrates a preferred arrangement for connecting adjoining
~ ~ .
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reflector-concentrators;
Figure 6 is a schematic representation of a repre-
sentative portion of the reflector-concentrators and collectors
of the embodiment of Figures 1-3, with the ganged collectors
being held horizontal during the parallelogram drive motion
thereof, while Figure 6A is a similar schematic representation
illustrating the arcuate tilting motion of the ganged collectors
in the modification of Figure 4; and
Figures 7 and 8 are diagrammatic illustrations of the
mode of operation of a single reflector-concentrator and col-
lector of the arrangement of Figure 1 at various times during
the year, Figure 8 also showing various angle and dimensional
~ relationships for a given preferred embodiment of a single
!' reflector-concentrator and collector.
Referring now in detail to the Figures of the draw-
ings, a heat utilization building structure, such as a house,
school, factory, etc., generally indicated at 11, has a roof/
reflector-concentrator surface 21, formed by a plurality of in-
dividual reflector-concentrators 31 and may also have a further
roof gurface or surfaces of any desired configuration if so
desired. The extent of roof/reflector-concentrator surface 21
is generally dependent upon the amount of solar energy needed
; for a given desired use. For maximum energy collection from
a given roof size, the entire roof may be formed as a reflector-
,~ concentrator assembly 21, as generally illustrated in the illus-
',! trative embodiment. Windows 15 and doors 17 may be provided in
j walls 13, as desired.
The roof/reflector-concentrator surface 21 is formed
by a plurality of laterally adjacent individual reflector-
connectors 31 which form effective water-tight roof sections
! ~ 4 -
and which are connected together at their lateral edges in sub-
stantially laterally adjoining relation to effect a water-tight
- roof construction. The interconnected reflector-connectors may
be suitably mounted and carried on the various upright and
cross members forming the load-bearing building framework 101,
as through the medium of complementary concave cradles generally
indicated at 36, which may be suitably spaced at the ends of
the individual reflectors 31, and otherwise located if desired
or needed for a given size or load. Side and end covers 32, 32a
may be suitably secured along the respective sides and ends of
the roof/reflector-concentrator surface 21 in order to effectively `~
seal the sides and ends of the roof against rain entry, and
gutters 111 may be provided along the ends of each bank of
reflector-concentrators 31, the illustrative embodiment having
two banks of reflector-concentrators 31 forming the roof 21, with
three gutters at the respective outboard opposite and adjacent ~-
opposing ends of the two banks of reflectors. Rain water will
thus be drained along the troughs formed by the reflectors 31
and into the gutters, from which the drain water may be dis-
charged to the ground as through suitable downspouts or down-
guttering (not shown) as necessary or desired.
A suitable facia generally indicated at 19 may be
provided as an aesthetic enclosure and wind break around the
reflector-concentrator roof 21, as desired, although there will
be a small sacrifice in overall efficiency due to end shadowing
from the facia on the reflectors 31 with the facia extending
above the reflectors to any appreciable extent.
Each reflector-concentrator 31 may be formed of any
suitable solar reflective material, such as metal, glassj plastic,
and such materials may be of load-bearing type and provide some,
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a major portion, or all of the roof surface construction strength
or may be of nonload-bearing substrate. The desired curvature
of each roof/reflector-concentrator 31 may be formed as a smooth
curve or as straight or curved line segments. For instance, a
curved metal roof surface may be formed in one continuous sweep,
or in several panels, or various normally straight panels of
metal, glass, plastic, etc. may be utilized in suitable joined
relation to form the desired overall curved shape roof/
reflector-concentrator surface 31. The roof 21 may also be
only partially reflective in parts thereof or in whole, if so
desired, in order to provide for natural lighting of the in-
terior of the building by light passage through the roof 21.
. ~
Similarly, the section 31 of the roof may also transmit light
to the building interior if 50 desired.
The roof/reflector-concentrators ~1 face upwardly
, preferably with their opposite ends oriented directly East-West
,; for maximum energy utilization, although other compass orienta-
tions may be utilized with less efficient operation.
Each roof/reflector-concentrator 31 reflects and
' 20 concentrates solar energy into a zone of maximum confluence
which varies in position as a function of the angle of the sun
with respect to the horizontal, as measured in a North-South
vertical plane passing through the roof 21. A solar energy
collector 51 is movably mounted, as by pivot arms 45, for
back-and-forth movement in a North-South direction above each
respective reflector-collector 31.
^~ The collector pivot support arms 45 are pivoted along
~ a horizontal East-West line which may extend beneath, above or
;~ at the surface of the respective reflector-concentrator 31, with
~ 30 generally only small differences in effectiveness of the
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reflector/collector assembly 31, 51. In the illustrative embodi-
ment, the arms 45 are mounted on pivot support bearings 81c
which lie beneath the surface of the roof reflector 21. In the
illustrative embodiment, as generally shown, the ratio of the
reflector chord/length subtended area versus the effective
collection area of the collectors 51 is approximately 15 to 1,
thereby providing a maximum feasible concentration or amplifica-
tion factor of no more than approximately 15 for an individual
reflector/collector unit 31, 51 considered alone, although some
spurious reflection from adjoining reflectors 31 may increase
the pickup to some extent. Other factors, such as angle of
inclination, interference of the collector 51 in passage of ~:~
the sun's rays to the reflector 31 (as at summer periods), re-
duce the maximum possible value to a lesser possible value for ~ ~
various solar angles. This factor further depends upon the ~ ;
extent of interception of the zone of solar reflection confluence
by the collector 51, as will be subsequently discussed in more
detail.
The pivoted support arms 45 are preferably ~uitably
ganged together as by linkage rods or beams 71 or the like to
provide simultaneous ganged motion of the various collectors 51
relative to their respective reflector-concentrators 31. Ganged
parallelogram movement of the pivoted support arms and hori-
zontal linkage beams 71 may be suitably effected as by pivoted
drive arms 81 connected through a torque tube 91 and pivotally
mounted in pivot support bearings 81c on cross-members of the
building framework 101, under one of the reflector-concentrators
31, as more particularly shown in Figure 3. A support brace 83
: may extend to aid in stabilizing the pivot pin 81a for drive arm
81. Pivoted back-and-forth motion of the drive arm 81 about its
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pivot 81a may be suitably effected by a drive motor M and screw
jack 84, the screw jack being preferably of the circulating ball
screw motion type, and this assembly M, 83 may be pivotally
pinned and carried between a pivot pin 83a carried by the build-
ing framework and a pivot pin 83b at the lower short legend of
the drive arm 81.
The pivoted support arms 45 may be suitably pivotally
mounted as indicated at 45a in respective bearings secured to
the building framework 101, and the upper ends of the arms 45 may
be pivotally secured to the horizontal linkage 71 through
respective pivot pins 45b. The effective lengths and angles of
arms 45 and 81 are the same, whereby effective parallelogram
motion may be effected for this collector movement assembly.
In the preferred embodiment of Figures 1-3 and 6, the
collectors 51 are maintained horizontal in their various posi-
tions above the respective reflector-concentrators 31, through
the securement of the ends of the collectors 51 to the horizontal
linkage beams 71, as through the medium of bolts 73. This
horizontal facing of the collectors 51 down toward their res-
pective reflectors aids in energy retention by the collectors
51 by minimizing heat losses particularly from convection loss
which is greater with a tilted altitude of the collector
receiving face.
Alternatively, though less desirably, the collectors
51 may be secured to the respective pivoted arms 345, as shown
in Figures 4 and 6A, and parallelogram motion of the arms 345 and
ganging linkage beam 371, pivotally interconnected as by pin
345b, will effect tilting movement of the collectors 51 as a
function of pivoted movement of the arms 345.
A preferred reflector-concentrator construction is
illustrated in Figure 3, in which glass mirror segments 31a are
cemented to a suitably curved sandwich formed of sheet metal 33,
rigid insulating foam 35, and sheet metal 37. This construction
enables the formation of a suitably rigid mirror reflector with
a desired curvature, and which will withstand the necessary
weather loads~ The various layers of the curved sandwhich 31a,
33, 35, and 37 may be suitably bonded together as a unit through
cement or the like, and multiple layers of foam 35 may be em-
ployed to enable ease of curve formation thereof particularly if
such is not precast in the desired curvature. The glass mirror
segments 31a may be omitted, with decrease in reflection
efficiency being effected for most other effectively utilizable
surfaces such as polished aluminum, steel, or other sheet metal
or the like as the reflector surface which might thus be formed
by the sheet 33 of the reflector 31 sandwich construction.
Other constructions for reflector-concentrators may be utilized,
as desired.
The reflector-concentrators 31 are suitably inter-
connected at their adjoining edges to effect a water-tight joint.
A suitable connecting arrangement is illustrated in Figure 5,
including male and female edge moldings 41, 43, which may be
formed as metal (e.g. aluminum, magnesium, steel, etc.) extru-
sions extending along all or a major portion of the length of
the adjoining reflector-concentrators 31. The male edge molding
43 has an upper male edge 43a which nests within a rubber seal-
ing gasket 44b disposed within a reverse lip 41a of the female
edge molding 41, and interfitting spacer ridges 41Q, 43Q run
along the intermediate lower ends of the respective moldings. A
further rubber sealing and mounting gasket 44a is compressed
between the moldings 41, 43 within the space above ridges 411,
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431, and the entire assembly 41, 43, 44a, 44b is secured together
through multiple longitudinally spaced bolts 47 and nuts 47a.
The longitudinal edges of adjoining reflector-concentrators 31
are retained between upper and lower angled flanges 41fu, 41fu
and 43fu, 43fu on the respective interfacing edge moldings 41
and 43.
Each collector 51 may be suitably formed with a
plurality of laterally side-by-side fluid flow heat transfer
tubes 57a, 57b through which a suitable fluid, such as water,
gas, etc. may be flowed for collection of the reflected solar
energy from its respective reflector-concentrator 31. These
tubes 57a, 57b may be connected for in-flow at one end and out-
flow at the other end of the collector 51, or preferably as
shown, may be reverse-flow interconnected at one end of the
collector for increased fluid flow path length within the con-
centrator as well as simplified external fluid interconnection `
thereto and therefrom. The parallel flow tubes 57a, 57b may be
suitable connected, as through flexible hose conduits 49a, 49b
carried in a common protective insulating sheath or jacket 49
with common feed and return conduits 47a, 47b. Feed and returnconduits 47a, 47b may be connected in parallel with in-flow and
out-flow side-by-side conduits 57a, 57b of each of the collectors
51, and a heat exchange fluid, preferably liquid, such as water
may be pumped through the conduits 47a, 47b, 49a, 49b, and 57a,
57b.
As shown in Figure 3, the collectors 51 are formed
with their respective reflected energy absorption elements 59,
57a, 57b facing downward toward the respective reflector-con-
centrator, and thereby enabling the interception of the solar
reflection thereto from reflector 31 at a given proper angle of
-- 10 --
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this assembly. Collectors 51 preferably are insulated at their
outer surfaces facing away from reflector 31, as by rigid or ;
other plastic foam or other suitable insulation 55, with a rigid
opaque wrap-around generally U-shaped structural beam-like cover
element 53, which may suitably be formed as a metal extrusion.
A solar energy transparent cover glass plate or plates 58 may be
secured beneath the energy absorption tubes 57a, 57b, with a down-
wardly finned black body heat-absorbing heat-sink block 59 secured
in spaced relation above the cover glass 58, as by anchoring in
the plastic foam insulation with a longitudinal ridge anchor
connector running along the length of the block 59. Elastic shock-
resistant seals such as soft rubber gasket seals 56 may suitably
retain the cover glass 59 within the beam cover element 53. The
fluid conduit tubes 57a, 57b are carried in intimate direct con-
tact with the finned black body heat-sink block 59, as by embed-
ding in the heat-sink block 59 or laying the tubes 57a, 57b in
longitudinal grooves in the upper side of the block 59 and crimp-
ing longitudinal lips adjoining the grooves down around the
tubes 57a, 57b, as illustrated. Heat adsorbed by the black body
finned heat-sink block will be conducted directly to the intimate-
ly held fluid passage tubes 57a, 57b and the fluid passing there-
through. This construction together with the horizontal position-
ing of the collectors 51 in their various lateral positions aids
in effecting a desired efficiency of energy collection and trans-
fer at the collectors while also minimizing energy losses which
may occur through convection with a tilted collector altitude.
Fluid feed and return lines 47a, 47b may be suitably
connected to a desired heat utilization system, such as a heat
storage and building interior heating arrangement, and/or a
30 cooling system, such as one based on absorption cooling ~;
- 1 1 - .
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principles.
Alternatively, various machinery may be caused to
perform work by the solar heat transferred to the fluid in
collectors 51, or other desired and suitable heat derived work
may be performed. With this invention, fluid temperatures, such
as for water as the fluid, may be raised to as high as 300F or
more, dependent on fluid flow rate, relative sizes of collector
and reflector, etc. Practical heating and absorption cooling
may be accomplished well within and below this temperature
extent for the fluid L flowed through the collector 51.
As shown particularly in Figures 7 and 8, the in-
dividual reflector-concentrators 31 each have a semi-cylindrical
concave reflecting surface which is formed of adjoining arcuate
segments SlA, S2, and SlB, the opposite outermost arcuate
; segments being preferably identical in radius and arcuate length
and being of lesser radius of curvature Rl, R3 than the radius
of curvature R2 of the central arcuate segment S2. Thus, the
concavely curved trough segments SlA and SlB curve up at a
sharper rate than does the central segment S2, and thereby aid
in maximizing overall confluence of the reflected solar rays
; into a zone for interception by the respective collector 51 at
various sun angles encountered throughout the year. Also, by
- providing a symmetrical trough-like concave reflector-concentra-
tor unit 31 the adjoining reflector-concentrators 31 may be
simply interconnected to form a roof of an overall flat, though
; obviously more detailedly undulating, envelope configuration
for use on building structures where such a roof is most
desirable, including particularly institutional, industrial,
and some residential buildings.
The vertically facing symmetrical three-radii
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1~3é3~
reflector-concentrator configuration is effective to provide a
substantial degree of concentration of solar energy onto the
collectors 51, the precise degree of concentration varying with
the sun angle, and varying generally from approximately 6:1 to
approximately 10 or 11:1 concentration ratio in the illustrative
embodiment for a latitude of approximately 28 North latitude.
As an illustration of the effective reflected sunlight envelope
intercepted by the collectors 51 at various times of the year,
Figure 8 diagrammatically shows the effective reflected solar
energy envelope zones intercepted by the collector in the
illustrative embodiment for various periods of the year, namely
at mid-day summer solstice, mid-day spring/fall equinox, and mid-
day winter solstice. The zones of effective reflection on the
mirror surface of reflector-concentrator 31 are indicated res-
pectively at SESM, SEF/SM and SEWM on this diagram.
A particular illustrative embodiment of the individual
reflector-concentrators 31 and collectors 51 for a latitude of
approximately 28, such as generally illustrated, may suitably
employ the following relationships, referring to Figure 7 for
20 reference characters and elements:
Radii Rl and R3 of front and rear arc
segments SlA and SlB 62 units
Radius R2 of center arc segment S2 81 units
Effective width CW of collector 51 6 units
Length of pivot arm 45 40-3/4 units
Length a 24 units
Lengths b and c, each 21 units
Length d 24 units
Length e 15-1/3 units
Length f 6-1/4 units
Length g 4 units
Arc segments SlA and SlB 27 units
,, : ': '. . , ~ ,
: - ' ' : ~ , : . .
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Arc segment S2 43 units
Minimum sun angle MNS desired to be
accommodated by collector 51 17 degrees
Maximum sun angle MXS desired to be
accommodated by collector 51 104 degrees
Minimum required angle MNC for collector/
arm assembly 51, 45 to accommodate
maximum desired sun angle (of
approximately 104 degrees) 7 degrees
Maximum required angle MXC for collector/
arm assembly 51, 45 to accommodate
minimum desired sun angle (of
approximately 18 degrees) 147 degrees
For other latitudes, particularly within the range of
. 10 0 to 40 or 50 latitudes, the same dimensions of this illustra-
tive reflector may be utilized, if desired, with a simple change
in the length of the pivot arm and the location of the pivot
position 45a for movement of collector 51 as determined by a
plot of the reflection angles of the sun from the various curved
surfaces of the reflector-concentrator at the various sun angles
encountered at the given latitude, and thereupon selecting the
optimum arcuate motion path for the collector 51, which will thus
dictate the arm 45 length and pivot 45a position. For instance,
for a latitude of approximately 39 North the length of arm 45 is
shortened to 32 units, with length f being lengthened to 21
. units and length g being zero, in order to obtain a desired
. extent of concentrated energy collection day by day throughout
the year, in this latitude location.
Determination of location of collectors 51 for each
solar angle may be precisely determined for a given reflector 31,
either by empirical plotting, or computer or other mathematical
; analysis of the confluence lines along the front-to-back extent
of the reflector with the collector positioned for the particular
desired maximizing of reflected solar energy interception at the
: 30 various sun angles, with such compromises between maximums at
~ - 14 -
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various angles as may be desired for a given location and utili-
zation. Positioning of the arms 45 and collectors 51 may be :
effected either on a predetermined control basis, or by energy
sensing and feedback control of the drive means for movement of
the collectors 51. As all of the reflector-concentrators 31 have
preferably substantially identical curvatures and collectors,
a single common control may thus be suitably employed for the
bank of reflector-concentrators 31 forming the roof 21, with its
associated collectors 51, based for instance on reflected energy-
10 sensing pickup at one of the collectors 51, or several such pick- ~:
ups may be employed and utilized as a common control. Obviously,
each arm 45 and collector 51 might also be separately driven and
controlled if so desired, though such will not normally be desir- :
able.
Desirably, arc segments SlA, S2 and SlB are smoothly
joined at a common point of tangency, a common tangency radius
line extending through the centers of radius RlC and R2C as well
as R2C and R3C for the three radii Rl, R2 and R3.
As previously noted, various zones of reflected solar i :;,
energy confluence for the illustrative embodiment are schematical- ;
ly shown in Figure 8, the zones being only approximately shown ~`
and representing the midday times at approximately 28N latitude : :
.
for the sun's position at noon on each of the winter solstice, .
summer solstice and spring and fall equinoxes. It has been found ; . .
that a good ratio of energy concentration and collection can be .~ ~ .
obtained over the major insolation periods of each day of the ~ ~ :
year by utilization of three or more radii for respectively three ~
or more of the sections of the roof reflector 21, the radii being :
lesser in length for arc segments increasingly spaced from the
30 lateral center of the respective reflector-concentrator 31. In ;~
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the illustrative example, three radii are satisfactorily employed,
the smaller Rl and R3 defining the central vertically facing re-
flector surface arc segment S2, as shown schematically in Figure
7. Referring again to Figure 8, it will be noted that at no sun
angle or reflection zone does the multiple-radii generated reflect-
or-concentrator 31 form a single focus line, but instead forms
various zones of confluence, and the size and location of the
zones of confluence vary with the sun angle, which in turn varies
both over the period of a year and during each day. In this res-
pect, inspection of the sun positions for the illustrative 28Nlatitude location readily show the requirements imposed on the
system in given days over the period of a year. These zones are
illustratively indicated in Figure 8, and designated as daily
movement aones for the collectors 51 and their supporting pivot
arms 45. It will be noted from Figure 8 that the reflector can
and does accommodate solar angles to a limited degree behind the
90 vertical. Of course, the side or end angle of inclination
must also be considered, and in order to maximlze solar energy
collection at low end angles the same as measured in the East-
West vertical plane, the reflectors 31 and collectors Sl shoulddesirably be relatively long along their length, particularly
with respect to the distance of the collectors 51 from the re-
flectors 31.
As the days approach the spring and fall equinoxes the :
daily excursions of movement required for the ganged arm/collector
assemblies 45, 51 decrease, until at the respective two equinoxes
the ganged arm/reflector assemblies 45, 51 require no angular
movement as the sun rises and sets on the East-West orientation
line of the reflector axes, and forms a constant angle throughout
the day as measured in a North-South vertical plane passing
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through the reflectors 31.
In the illustrative embodiment, the solar concentration
factors, or amplification factors, vary with the solar angle.
The concentration or amplification factor is a function of the
extent of coverage or interception of the zone of confluence of
the reflected solar energy at a given sun angle, and it is there~
fore desirable to maximize this extent of interception at the
various angular positions of the sun and the collector/arm
assemblies 51, 45, insofar as is practical and economical.
It has been founa that by mounting the arms 45 on respective
pivot axes near the surface of reflectors, as at, above or pre-
ferably beneath the reflector surface, an adequate extent of
interception of the various zones of solar energy confluence may
be obtained for the collector Sl. In the illustrative embodiment
the horizontal pivot line for pivot support arms 45 is disposed
slightly beneath the effective reflective surface of respective
reflectors 31, and is spaced from the center of longitudinal
center line of the reflector 31 in a direction away from the
Equator, the extent of desired displacement varying with the
latitude of the user location. However, this arm pivot line may : .
if desired be otherwise located for a given embodiment, as for :
instance above or at the surface of reflector 31.
In the modification illustrated in Figure 2A, the common
center pivot arms 45 for the longitudinally paired collectors 51
of the two banks of reflectors 31 are replaced by separate indi-
vidual center zone individual pivot support arms 245, and the
respective longidutinally paired collectors 51 of the two side-
by-side banks of reflector/collector units are individually tied
together only ~hrough the common drive torque tube 91 which
serves to impart pivotal movement to the parallelogram linkage
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45, 81, 71, 245, 271, 81, 245, 271, 81, etc. for each end of the
ganged groups of collectors 51, 51 etc.
It will, of course, be appreciated that all of the
drawings are only illustrative and are not themselves intended to
be illustrated necessarily in true size relationships, although
such is to some extent approximately the case, as particularly in
Figure 7. This observation applies also to the zones of solar
reflection confluence and the collector 51 interception zones,
although such are shown to give a fairly indicative illustration
of the principles and mode of operation and practice involved.
The typical specific illustrative example proportions
as previously shown and described, particularly with respect to
Figure 7, are, as previously noted, for an embodiment and practice
of the invention primarily within a latitude of approximately
28. Also, as noted, the embodiment is arranged such that the
concentration factors for summer, spring and fall solar energy
collection are maximized, to some extent at the expense of
winter concentration factors, in order to maximize available
solar-derived heat energy for air conditioning, (although still
enabling the satisfaction of minimum requirements for heating
during at least the major portion of most winter conditions).
While the invention has been illustrated and described
with respect to particular illustrative embodiments and modes of
practice, and various possible modifications have been described,
it will be appreciated that various further modifications and
improvements may be made without departing from the scope and
spirit of the invention. For lnstance, the reflectors 31 may be
formed as a single or multiple reflector assembly only, and not
as a roof of a building, although this is normally the most
advantageous and preferred embodiment. Further, while a pivoted
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1~13B:~3
support arm arrangement 45, and particularly a ganged movement
arrangement, is illustrated and preferred for supporting and
moving the collectors 51 through the desired zone of movement,
various other collector supporting and movement arrangements may
be employed. Also, while three radii Rl, R2 and R3 are employed
in the illustrative example, especially for simplicity of design
and construction, more than three radii may be suitaly employed,
graduating from shortest at the front and rear to the longest at
the center zone of the reflector-concentrator 31, and may in fact ~:
be constructed with a continuously varying radius from front to
back of the reflector 31. Such a continuously varying radius
reflector 31 may, however, be beyond the desired complexity for .
normal construction and the triple radius construction is con- ~-
sidered to be adequate and most easily constructed from a practi- : ~
cal standpoint. Accordingly, the invention is not to be limited ::
to the particular illustrative embodiment and mode of operation :
and practice, but only by the scope of the appended Claims.
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