Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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COVER FOR SOLAR PANEL
BACKGROUND INFORMATION
[0001] FIELD OF THE INVENTION
[0002] The invention relates to covers for solar panels. More particularly,
the
invention relates to covers for solar panels that are exposed to intense solar
radiation.
[0003] DESCRIPTION OF THE PRIOR ART
[0004] Solar panels that absorb solar energy for the purpose of heating, be it
water or space, are sometimes at risk of overheating. An example of such a
case is that of a solar system for heating water in a facility that is open
only
seasonally, such as a camp or ski lodge. In the case of a structure that is
only
seasonally occupied, the water in the heater tubes remains stagnant during the
periods of non-use. Heat builds up and is only poorly dissipated if the water
is
not being circulated through the system. Such solar panels are also at risk of
overheating even during times of usage, if, for example, the panels are
exposed
to long and intense periods of solar radiation, such as in the summer. Thus,
in a
residential structure that is occupied year-round in many parts of the US and
that
uses solar panels to obtain hot water, solar radiation in the summer may be
very
intense. The demand for hot water may not be sufficient to dissipate the heat
quickly enough, particularly if the house is unoccupied because the residents
are
away on vacation. Solar energy panels that are used to provide heated water
for
radiant space heating of a structure, as well as hot water, are particularly
at risk
of overheating. These solar panels contain sufficient heat panels to satisfy
the
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heat load in winter months. Once the cold weather is over, the solar panels
are
subject to risk of overheating, because the demand is so much reduced.
[0005] What is needed, therefore, is a protective cover for solar panels,
whether the solar panels are so-called flat panels or panels comprising an
array
of evacuated tubes. What is further needed is such a cover that is easily and
quickly moved between an open position and a closed position.
BRIEF SUMMARY OF THE INVENTION
[0006] The invention is a cover for use with solar panels. The cover provides
protection from the elements of the weather, such as snow, hail, sleet,
debris,
and rain. The cover is also a solar radiation blocker and provides protection
against overheating of the solar panel when it is subjected to intense solar
radiation.
[0007] The cover according to the invention must be removable or
positionable, so as to allow the solar rays to impinge upon the solar panel
when
desired. The cover has an outer surface or outer protective shell that is
weather-
resistant and an inner shell or inner portion that has heat-insulative
properties, to
protect the solar panel from overheating. Various embodiments of the cover are
provided herein according to the invention; some embodiments are manually
fitted over and then removed from the solar panel, others are mechanically
operated to cover and uncover the solar panel. Mechanically operated covers
may have a wind-up mechanism that is manually operated, such as a crank that
winds the cover around a shaft, have an electrically driven mechanism, such as
a
motor and linkages to wind the cover around a shaft or draw the cover up into
a
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compact pleated or bunched configuration, or have segmented portions that are
moved to an open or closed position in order to cover or uncover the solar
panel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0008] FIG. 1 is a perspective view of the top of a rigid, removable
protective
cover according to the invention.
[0009] FIG. 2 is a perspective view of the bottom of the cover of FIG. 1.
[0010] FIG. 3 is an cross-sectional view of the cover of FIG. 1.
[0011] FIG. 4 is a perspective view of the top of a soft, removable protective
cover according to the invention.
[0012] FIG. 5 is a perspective view of the bottom of the cover of FIG. 4.
[0013] FIG. 6 is a cross-sectional view of the soft cover of FIG. 4.
[0014] FIG. 7 is a perspective view of a third embodiment of the cover.
[0015] FIG. 8 is a perspective view of a fourth embodiment of the cover.
[0016] FIG. 9 is a side view of the cover shown in FIG. 8, illustrating
linkages
and connecting rods that are actuated move the protective panel sections to
open and closed positions.
[0017] FIG. 10 is a side view of the cover of FIG. 8, showing the cover
closed.
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DETAILED DESCRIPTION OF THE INVENTION
[0018] The present invention will now be described more fully hereinafter with
reference to the accompanying drawings. This invention may be embodied in
many different forms and should not be construed as limited to the embodiments
set forth herein. Rather, the embodiments shown are provided so that this
application will be thorough and complete, and will fully convey the true
scope of
the invention to those skilled in the art. Like numbers refer to like elements
throughout the figures.
[0019] A conventional solar panel 4 is shown in several of the following
drawings mounted on a conventional frame F. The frame F may be constructed
so as to mount the solar panel 4 in an orientation that is parallel to an
underlying
surface, or be constructed to provide an incline that increases the direct
impingement of the rays from the sun. The frame F is not included within the
scope of the invention and is shown here only insofar as necessary to
illustrate
the inventive covers.
[0020] FIGS. 1 - 3 illustrate a first embodiment of a solar panel cover 10
that
is a rigid cover and FIG. 4 - 6 illustrate a second embodiment of a cover 20
that
is a soft cover. These two covers 10 and 20 are manually removable covers.
FIG. 1 is a perspective view of the top, FIG. 2 a view of the bottom, and FIG.
3 a
cross-sectional view of the rigid cover 10. The cover 10 comprises an outer
shell
or layer 1 constructed of a form-rigid material, a shock-absorption and/or
insulative layer 3, and straps 7 to secure the cover 10 to a solar panel 4.
The
solar panel 4 is shown only schematically in FIG. 3 The rigid cover 10 is used
preferably on a solar panel that is a flat-plate type panel. Water-conducting
tubes lead into and out of the conventional solar panel and flaps or openings
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are provided on the side walls of the outer shell I to accommodate these
tubes.
The straps 7 include corner straps 6 and/or a long strap 7A that extends
across
the underside of the solar panel 4. The outer shell or layer I is ideally
constructed of a material that is rot and mildew resistant, such as a
lightweight
manufactured material, including a metallic material. The shock-absorbing or
insulative layer 3 is preferably constructed of a foam or other compressible
material. The outer layer 1 and the insulative layer 3 may be laminated to
each
other, to provide a single fabric. It is also possible to use a material that
combines both desired properties, i.e., weather resistance and heat
insulation, to
form the covers 10, 20.
[0021] FIGS. 4 - 6 illustrate a second embodiment of a solar panel cover 20
that is a soft cover that is particularly well suited to fit over solar panels
that are
arrays of evacuated tubes. The cover 20 comprises an outer shell 21 and a
shock-absorption or insulative layer 22 and is manually removable from the
solar
panel 4. The outer shell 22 is ideally constructed of a flexible fabric, such
as
canvas or other flexible fabric that is rot and mildew resistant. The shock-
absorption layer 22 is a layer of foam or other compressible material. The
outer
shell 21 may be secured to the solar with straps 7 similar to those described
in
connection with the cover 10. It may also, instead of the straps 7, have an
elastic
edge 21A that allows the fabric to fit around the solar panel 4 and enclose
the
edges of the panel so as to secure the cover 20 to the panel 4.
[0022] The outer shells 1, 21 may be constructed of or coated with a
reflective
material to reduce the solar radiation that impinges on the cover.
[0023] FIG. 7 is a perspective view of a third embodiment 30 of a solar panel
cover according to the invention for the solar panel 4. The cover is
constructed
of a rollable material 32, such as, for example, a flexible sheet fabric or a
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of slats that allow the cover 30 to roll up or fold up with pleats. A storage
enclosure 34 is provided, for receiving the rolled-up or pleated portion of
the
cover 30. The mechanism for moving the cover 30 between a deployed or
closed position and a non-deployed or open position is a conventional
mechanism, such as is used for electrically operating large awnings, and is
not
shown in any detail. The mechanism may be manually operated or motor-driven.
Ideally, the mechanism is motor-driven with an operating switch that is
conveniently located for easy access. The cover 30 has sides 32A that are
captured in a track 36. The mechanism for rolling and unrolling the cover
forces
the sides 32A along the track 36, so as to cover or uncover the solar panel 4
as
desired. The flexible sheet fabric may be stitched at regular intervals to
facilitate
pleating. Preferably, the cover 30 includes an outer surface that is weather-
resistant and heat-insulative properties. The cover may comprise an outer
weather-resistant layer and an inner heat-insulative layer, or be constructed
of a
material that combines both desired properties.
[0024] FIGS. 8 - 10 illustrate a fourth embodiment 40 of a solar cover
according to the invention for the solar panel 4. This embodiment includes a
series of cover vanes or segments 42 that are mounted on a linkage system 46,
so as to be movable from an open position, shown in FIGS. 8 and 9 and a closed
position, shown in FIG. 10. The cover includes a motor-driven linkage system
46
that is coupled with the segments 42. The linkage system 46 includes a pair of
linkage rods, a first rod 46A and a second rod 46B, each of which are
connected
to the segments 42 as shown in FIG. 9. The first rod 46A is connected to an
outer portion 46C and the second rod to a center portion 46D of each segment
42. A motor M drives the linkages so as to shift the segments 42 between an
open and a closed position. In the embodiment shown, the motor M is enclosed
in protective enclosure 44. The segments 42 may be constructed of a sheet
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metal or plastic material. As with the other embodiments of the cover
described
herein, the outer surface or shell of the segments 42 may be constructed of a
weather-resistant material and the inner portion or inner shell be constructed
of a
material that provides the desired insulative properties to block excessive
solar
radiation and prevent the solar panel from overheating.
[0025] Sensors may be used with any motor-driven system to move the cover
between the deployed and non-deployed positions, depending on weather
conditions. For example, a temperature sensor 50, shown in FIG. 7, may be
coupled with any motor-driven means for moving the cover, to close the cover
when the temperature on the solar panel exceeds a threshold value and/or to
open the cover when the temperature drops below a certain value. Shock
sensors may be used in areas that are prone to severe hail storms, to close
the
cover when impact forces that exceed a predetermined threshold value impinge
on the solar panel.
[0026] The foregoing is considered as illustrative only of the principles of
the
invention. The dimensional relationships for the covers 10, 20, 30, 40 include
variations in size, materials, shape, form, function and manner of operation,
assembly and use. All equivalent relationships to those illustrated in the
drawings and described in the specification are included in the scope of the
present invention.
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