U.S. patent application number 14/169997 was filed with the patent office on 2014-05-29 for ground mounted solar module integration system.
This patent application is currently assigned to PANELCLAW, INC.. The applicant listed for this patent is PANELCLAW, INC.. Invention is credited to David Anderson, Joseph Armano, Vasilije Jovanovic.
Application Number | 20140145059 14/169997 |
Document ID | / |
Family ID | 50237518 |
Filed Date | 2014-05-29 |
United States Patent
Application |
20140145059 |
Kind Code |
A1 |
Anderson; David ; et
al. |
May 29, 2014 |
GROUND MOUNTED SOLAR MODULE INTEGRATION SYSTEM
Abstract
Embodiments of the present inventions are directed to systems,
devices for use with systems, and method of mounting and retaining
solar panels. In some embodiments, an apparatus for mounting one or
more solar panel modules above a supporting surface is disclosed,
the apparatus including: three foundational members embedded in the
supporting surface; a support frame configured to receive the solar
panel modules; a support strut assembly configured to attach the
support frame to the three foundational members to support the
solar panel modules; where the support strut assembly includes a
plurality of strut members, and includes one or more adjustment
mechanisms that may be used to adjust a length or a joining angle
of at least one of the strut members.
Inventors: |
Anderson; David; (Wellesley,
MA) ; Jovanovic; Vasilije; (Winchester, MA) ;
Armano; Joseph; (North Andover, MA) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
PANELCLAW, INC. |
North Andover |
MA |
US |
|
|
Assignee: |
PANELCLAW, INC.
North Andover
MA
|
Family ID: |
50237518 |
Appl. No.: |
14/169997 |
Filed: |
January 31, 2014 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/US2013/029629 |
Mar 7, 2013 |
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14169997 |
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61698202 |
Sep 7, 2012 |
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61758210 |
Jan 29, 2013 |
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Current U.S.
Class: |
248/550 ;
29/428 |
Current CPC
Class: |
Y02E 10/47 20130101;
Y10T 29/49826 20150115; Y02E 10/50 20130101; Y02B 10/20 20130101;
F24S 25/00 20180501; F24S 25/617 20180501; H01L 31/042 20130101;
H02S 20/00 20130101; F24S 25/13 20180501 |
Class at
Publication: |
248/550 ;
29/428 |
International
Class: |
H01L 31/042 20060101
H01L031/042 |
Claims
1. A system for mounting one or more solar panel modules above a
supporting surface, the system comprising: a positioning device
configured to: position a support frame bearing the solar panels at
a rough position relative to one or more foundational members
embedded in the surface; acquire fine position information
indicative of the position and orientation of the support frame
relative to a reference point; adjust the position and orientation
of the support frame to a final position based at least in part of
the fine position information; wherein the positioning device
comprises a hexapod; and wherein the hexapod is mounted on a
vehicle.
2. The system of claim 1, further comprising a total positioning
system configured to determine the fine position information.
3. The system of claim 2, wherein the total positioning system is
configured to determine a roll, pitch and yaw of the support
frame.
4. The system of claim 2, further comprising a support strut
assembly configured to attach the support frame to the foundational
members to support the solar panel modules; wherein the support
strut assembly is comprised of a plurality of strut members, and
comprises one or more adjustment mechanisms may be used to adjust a
length or a joining angle of at least one of the strut members.
5. The system of claim 3, wherein the plurality of strut members
comprises at least six strut members, and wherein each of the strut
members has a respective adjustment mechanism.
6. The system of claim 4, wherein the support strut assembly is
adjustable using six degrees of freedom to allow the support frame
to be attached to three foundational members at a selected position
and orientation.
7. The system of claim 5, wherein the support strut assembly is
configured to be attached to the foundational members and the
support frame such that the plurality of strut members are
configured to experience substantially only tension and compression
forces.
8. The system of claim 1, wherein the hexapod is configured to lift
the support frame from a stack of support frames.
9. The system of claim 1, wherein the hexapod includes a position
sensor to determine a position of the support frame.
10. The system of claim 1, wherein the hexapod includes a plurality
of hydraulic legs.
11. A method for mounting one or more solar panel modules above a
supporting surface, the method comprising: positioning a support
frame bearing the solar panels at a rough position relative to one
or more foundational members; acquiring fine position information
indicative of the position and orientation of the support frame
relative to a reference point; adjusting the position and
orientation of the support frame to a final position based at least
in part of the fine position information; and using a hexapod to
adjust the position and orientation of the support frame, wherein
the hexapod is mounted on a vehicle, and wherein the vehicle is
used to position the support frame at the rough position.
12. The method of claim 11, further comprising using a total
positioning system to determine the fine position information.
13. The method of claim 12, further comprising, while the
positioning device holds the frame in the final position, using a
support strut assembly configured to attach the support frame to
foundational members to support the solar panel modules.
14. The method of claim 13, wherein the support strut assembly is
comprised of a plurality of strut members, and comprises one or
more adjustment mechanisms that may be used to adjust a length or a
joining angle of at least one of the strut members.
15. The method of claim 14, wherein the plurality of strut members
comprises at least six strut members, and wherein each of the strut
members has a respective adjustment mechanism.
16. The method of claim 15, wherein the support strut assembly is
adjustable using six degrees of freedom to allow the support frame
to be attached to the three foundational members at a selected
position and orientation.
17. The method of claim 16, further comprising attaching the
support strut assembly to the foundational members and the support
frame such that the plurality of strut members are configured to
experience substantially only tension and compression forces.
18. The method of claim 11, further comprising lifting, by the
heaxapod, the support frame from a stack of support frames.
19. The method of claim 11, further comprising using, by the
hexapod, a position sensor to determine a position of the support
frame.
20. The method of claim 11, further comprising using, by the
hexapod, a plurality of hydraulic legs to position the support
frame for installation.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] The present application claims priority to and is a
continuation of International Patent Application No.
PCT/US2013/029629 entitled "Ground Mounted Solar Module Integration
System" filed Mar. 7, 2013, which claims priority to U.S.
Provisional Application No. 61/758,210 entitled "Ground Mounted
Solar Module Integration System" filed Jan. 29, 2013, and U.S.
Provisional Application No. 61/698,202 entitled "Ground Mounted
Solar Module Integration Systems" filed Sep. 7, 2012. The contents
of each of the foregoing are hereby incorporated herein by
reference.
BACKGROUND
[0002] Embodiments disclosed herein are directed to systems,
devices for use with systems, and methods of mounting and retaining
solar panels.
[0003] Solar (e.g., photovoltaic) panels are often manufactured in
the form of flat rigid structures. To facilitate the performance of
the function of generating electricity, solar panels may be mounted
in an area exposed to the sun or other source of light. Often, it
is desirable to mount solar panels outdoors at an angle from the
horizontal so that they will more directly face the sun during peak
daylight hours as opposed to panels mounted flat on the ground. In
some applications, it may be desirable to mount a number of solar
panels together in an array in order to combine the power
generation capabilities of the individual panels. In many
instances, it may be desirable that mounting systems for solar
panel arrays retain the solar panels in place. This may be
accomplished by attaching the solar panels to one another in a
mounting system and/or by mounting the panels to the mounting
system.
[0004] For example, U.S. Patent Application Publication No.
2007/0133474 to Mascolo et al. describes a supported solar panel
assembly including a solar panel module comprising a solar panel
and solar panel module supports including module supports having
support surfaces supporting the module, a module registration
member engaging the solar panel module to position the solar panel
module on the module support, and a mounting element. U.S. Pat. No.
6,534,703 to Dinwoodie describes a solar panel assembly for use on
a support surface comprising a base, a solar panel module, a
multi-position module support assembly, and a deflector.
SUMMARY
[0005] Devices, systems, and techniques are disclosed for mounting
and retaining solar panels. In some embodiments, solar panels are
mounted in arrays on the ground, e.g. in an open field. In some
embodiments, the ground includes local surface undulations, and the
array of solar panels may be constructed to compensate for these
undulations.
[0006] In one aspect an apparatus is disclosed for mounting one or
more solar panel modules above a supporting surface, including:
three foundational members embedded in the supporting surface; a
support frame configured to receive the solar panel modules; and a
support strut assembly configured to attach the support frame to
the three foundational members to support the solar panel modules.
The support strut assembly includes a plurality of strut members,
and includes one or more adjustment mechanisms that may be used to
adjust a length or a joining angle of at least one of the strut
members.
[0007] In some embodiments, the plurality of strut members includes
at least six strut members, and each of the strut members has a
respective adjustment mechanism.
[0008] In some embodiments, the support strut assembly is
adjustable using six degrees of freedom to allow the support frame
to be attached to the three foundational members at a selected
position and orientation.
[0009] In some embodiments, the support strut assembly is
configured such that the plurality of strut members are configured
to experience substantially only tension and compression
forces.
[0010] In some embodiments, the three foundational members are
arranged in a triangular configuration having two rear foundational
members and one front foundational member, and the support strut
assembly includes a front support structure that includes two
struts joined at their base on the front foundational member 140
and two side support structures, each of which consists of two
struts joined at their base and resting on top of a respective one
of the two rear foundational members.
[0011] In some embodiments, the support strut assembly includes a
cross brace.
[0012] In one aspect, a method is disclosed for mounting one or
more solar panel modules above a supporting surface. The method
includes locating three foundational members embedded in the
supporting surface; providing a support frame bearing the solar
panel modules; attaching the support frame to the three
foundational members using a support strut assembly to support the
solar panel modules. The support strut assembly includes a
plurality of strut members, and includes one or more adjustment
mechanisms that may be used to adjust a length or a joining angle
of at least one of the strut members.
[0013] In some embodiments, the plurality of strut members includes
at least six strut members, and each of the strut members has a
respective adjustment mechanism.
[0014] In some embodiments, the support strut assembly is
adjustable using six degrees of freedom to allow the support frame
to be attached to the three foundational members at a selected
position and orientation.
[0015] In some embodiments, the method further includes attaching
the support strut assembly to the foundational members and the
support frame such that the plurality of strut members are
configured to experience substantially only tension and compression
forces.
[0016] In some embodiments, the three foundational members are
arranged in a triangular configuration having two rear foundational
members and one front foundational member, and the support strut
assembly includes a front support structure that includes two
struts joined at their base on the front foundational member and
two side support structures, each of which consists of two struts
joined at their base and resting on top of a respective one of the
two rear foundational members.
[0017] In some embodiments, the method further includes attaching a
cross brace to the support strut assembly.
[0018] In one aspect, a system is disclosed for mounting one or
more solar panel modules above a supporting surface, including: a
positioning device for positioning a support frame bearing the
solar panels at a rough position relative to one or more
foundational members embedded in the surface; acquiring fine
position information indicative of the position and orientation of
the support frame relative to a reference point; and adjusting the
position and orientation of the support frame to a final position
based at least in part of the fine position information.
[0019] In some embodiments, the positioning device includes a
hexapod.
[0020] In some embodiments, the hexapod is mounted on a
vehicle.
[0021] In some embodiments, the system further includes a total
positioning system configured to determine the fine position
information.
[0022] In some embodiments, the system further includes a support
strut assembly configured to attach the support frame to the
foundational members to support the solar panel modules. The
support strut assembly includes a plurality of strut members, and
includes one or more adjustment mechanisms may be used to adjust a
length or a joining angle of at least one of the strut members.
[0023] In some embodiments, the plurality of strut members includes
at least six strut members, and wherein each of the strut members
has a respective adjustment mechanism.
[0024] In some embodiments, the support strut assembly is
adjustable using six degrees of freedom to allow the support frame
to be attached to three foundational members at a selected position
and orientation.
[0025] In some embodiments, the support strut assembly is
configured to be attached to the foundational members and the
support frame such that the plurality of strut members are
configured to experience substantially only tension and compression
forces.
[0026] In one aspect, a method is disclosed for mounting one or
more solar panel modules above a supporting surface. The method
includes positioning a support frame bearing the solar panels at a
rough position relative to one or more foundational members;
acquiring fine position information indicative of the position and
orientation of the support frame relative to a reference point; and
adjusting the position and orientation of the support frame to a
final position based at least in part of the fine position
information.
[0027] In some embodiments, the method further includes using a
hexapod to adjust the position and orientation of the support
frame.
[0028] In some embodiments, the hexapod is mounted on a vehicle,
and the vehicle is used to position the support frame at the rough
position.
[0029] In some embodiments, the method further includes using a
total positioning system to determine the fine position
information.
[0030] In some embodiments, the method further includes using a
support strut assembly configured to attach the support frame to
foundational members to support the solar panel modules while the
positioning device holds the frame in the final position.
[0031] In some embodiments, the support strut assembly includes a
plurality of strut members, and includes one or more adjustment
mechanisms that may be used to adjust a length or a joining angle
of at least one of the strut members.
[0032] In some embodiments, the plurality of strut members includes
at least six strut members, and each of the strut members has a
respective adjustment mechanism.
[0033] In some embodiments, the support strut assembly is
adjustable using six degrees of freedom to allow the support frame
to be attached to the three foundational members at a selected
position and orientation.
[0034] In some embodiments, the method further includes attaching
the support strut assembly to the foundational members and the
support frame such that the plurality of strut members are
configured to experience substantially only tension and compression
forces.
[0035] Various embodiments may include any of the above described
elements, either alon, or in any suitable combination.
BRIEF DESCRIPTION OF DRAWINGS
[0036] The accompanying drawings are not intended to be drawn to
scale. In the drawings, each identical or nearly identical
component that is illustrated in various figures is represented by
a like numeral. For purposes of clarity, not every component may be
labeled in every drawing. In the drawings:
[0037] FIG. 1A is a perspective view of a module mount assembly
supporting several solar panel modules;
[0038] FIG. 1B is a top view of the module mount assembly of FIG.
1A;
[0039] FIG. 1C is a rear view of the module mount assembly of FIG.
1A;
[0040] FIG. 1D is a side view of the module mount assembly of FIG.
1A;
[0041] FIG. 2 is a top view of the foundational components of a
system for mounting an array of solar panels;
[0042] FIG. 3A is a helical pile;
[0043] FIG. 3B is an I-beam pile;
[0044] FIG. 3C is an earth screw;
[0045] FIG. 4A is a perspective view of a support strut assembly
that can be used for mounting an array of solar panels;
[0046] FIG. 4B is a top view of the support strut assembly of FIG.
4A;
[0047] FIG. 4C is a rear view of the support strut assembly of FIG.
4A;
[0048] FIG. 4D is a side view of the support strut assembly of FIG.
4A;
[0049] FIG. 5 is a strut used in the support strut assembly of
FIGS. 4A-4D;
[0050] FIG. 6A is a three support strut ball clamp;
[0051] FIG. 6B is a two support strut ball clamp;
[0052] FIG. 6C is a single support strut ball clamp;
[0053] FIG. 6D is a frame connection ball clamp;
[0054] FIG. 7 is a perspective view of a support strut assembly
spacer frame;
[0055] FIG. 8A is a top view of a module frame configured for
installation;
[0056] FIG. 8B a top view of the module frame of FIG. 8A configured
for shipment;
[0057] FIG. 9A is a top view of a first alternative module frame
configured for installation;
[0058] FIG. 9B is a top view of the module frame of FIG. 9A
configured for shipment;
[0059] FIG. 9C is a top view of a second alternative module frame
configured for installation;
[0060] FIG. 9D is a top view of the module frame of FIG. 9C
configured for shipment;
[0061] FIG. 10A is a perspective view of a nested module frame;
[0062] FIG. 10B is an enlarged view of a portion of the nested
module frame of FIG. 10A;
[0063] FIG. 11A is an under-clamp for securing a module frame to a
spar;
[0064] FIG. 11B is the under-clamp of FIG. 11A installed to secure
a module frame and a spar;
[0065] FIG. 12A is an over-clamp for securing a module frame to a
spar;
[0066] FIG. 12B is the over-clamp of FIG. 12A installed to secure a
module frame and a spar;
[0067] FIG. 13A is a system for automating the installation of an
array of solar panel modules;
[0068] FIG. 13B is an enlarged view of a hexapod used in the system
of FIG. 13A;
[0069] FIG. 14 is an automated method for installing an array of
solar panel modules;
[0070] FIG. 15 is a manual method for installing an array of solar
panel modules;
[0071] FIG. 16A is a perspective view of a strut-pile
connection;
[0072] FIG. 16B is an exploded view of a strut for use in the
strut-pile connection of FIG. 16A;
[0073] FIG. 16C is perspective view of a strut-pile connection
prior to installation of the strut;
[0074] FIG. 16D is an enlarged view of a strut-pile connection;
[0075] FIG. 16E is a perspective view of a strut-frame
connection;
[0076] FIG. 17A is a side view of a midclaw for securing two solar
panel modules in an uninstalled configuration;
[0077] FIG. 17B is a side view of the midclaw of FIG. 17A in its
fully installed configuration;
[0078] FIG. 17C is an end view of the midclaw of FIG. 17A in its
fully installed configuration;
[0079] FIG. 18A is a side view of an endclaw for securing a solar
panel module at the end of a module array in an uninstalled
configuration;
[0080] FIG. 18B is a side view of the endclaw of FIG. 18A in its
fully installed configuration;
[0081] FIG. 18C is an end view of the endclaw of FIG. 18A in its
fully installed configuration.
DETAILED DESCRIPTION
[0082] The embodiments described herein are not limited to the
details of construction and the arrangement of components set forth
in the following description or illustrated in the drawings. The
embodiments are capable of other embodiments and of being practiced
or of being carried out in various ways. Also, the phraseology and
terminology used herein is for the purpose of description and
should not be regarded as limiting. The use of "including,"
"comprising," or "having," "containing," "involving," and
variations thereof herein, is meant to encompass the items listed
thereafter and equivalents thereof as well as additional items. The
description of one aspect of the embodiments disclosed herein is
not intended to be limiting with respect to other aspects of the
present embodiments.
[0083] FIG. 1A illustrates an example of a section of a module
mount assembly 100 for supporting solar panel modules 110 that may
be deployed on a mounting surface, for example, an area of open
ground such as a field. Aspects of the present implementations may
be applied to other mounting surfaces, such as roof structures.
[0084] The module mount assembly 100 in this example supports
twelve solar panel modules 110 arranged in a rectangular grid, but
in various embodiments, any number and arrangement of modules may
be used. In some embodiments, the solar panel module 110 is a
packaged interconnected assembly of solar cells, e.g., photovoltaic
cells. In some embodiments, the solar panel module may be used as a
component in a larger photovoltaic system to offer electricity for
commercial and residential applications.
[0085] The solar panel modules 110 are illustrated in FIG. 1A as
being mounted at an angle from the horizontal, but in some
embodiments, the solar panel modules may be mounted at angles other
than that illustrated in FIG. 1A or even horizontally. The solar
panel modules 110 may in some embodiments be mounted at different
angles throughout the module mount assembly 100 and uniformly in
others such as the one shown in FIG. 1A. The solar panel modules
110 are shown in FIG. 1A facing away from what will be described
herein as the Top side of module mount assembly 100. What is
described as the Top side may correspond to geographical North
position of the module mount assembly 100. As shown here, the Top
side may be positioned approximately to the North so that the
tilted faces of the panel modules are directed generally toward the
South, e.g., tilted to more squarely face the direction of the sun
for an installation north of the equator. In some embodiments,
deflector elements (not shown) may be mounted facing the lateral
sides (i.e., the sides perpendicular to the Top side) at the edges
of the module mount assembly 100, or in other positions on the
module mount assembly 100 to deflect wind currents. Of course, in
various embodiments, any other suitable arrangement may be
used.
[0086] Solar panel modules 110 in this example are mounted on a
module frame 120 which is in turn mounted on a support strut
assembly 130. The support strut assembly 130 is mounted on a
foundation 140. A support frame is a support structure that may be
used to support at least a portion of a solar panel; in this
example, the module frame 120 is used to support twelve solar panel
modules 110. A support strut assembly is an adjustable support
structure which supports the module frame 120 and the solar panel
modules 110. A foundation is a structure that contacts the ground
and provides support for the support strut assembly 130, the module
frame 120, and the solar panel modules 110. Examples of the
foundation 140, the support strut assembly 130, and the module
frame 120 are described more fully below.
[0087] FIG. 1B illustrates a top view of the module mount assembly
100 of solar panel modules 110 depicted in FIG. 1A. As shown in
FIG. 1B, the module mount assembly includes 12 solar panel modules
110, arranged in a coplanar configuration. Although the solar panel
modules 110 are shown arranged in 3 columns and 4 rows
("3.times.4"), other configurations are possible. For example, in
other implementations, the solar panel modules 110 can be arranged
in 4 columns.times.3 rows, 2 columns.times.6 rows, or 6
columns.times.2 rows, etc. Also shown in FIG. 1B are the portions
of the module frame 120 that extend slightly beyond the edges of
the solar panel modules 110.
[0088] FIG. 1C illustrates a rear view of the module mount assembly
100 of solar panel modules 110 depicted in FIG. 1A. The support
strut assembly can include a cross brace 132. In other
implementations, the support strut assembly does not include the
cross brace 132.
[0089] FIG. 1D illustrates a side view of the module mount assembly
100 of solar panel modules 110 depicted in FIG. 1A. As depicted in
FIG. 1B, the solar panel modules 110 can be configured at an angle
relative to the ground. In some implementations, the angle is
selected to maximize exposure of the top surfaces of the solar
panel modules 110 to the sun or other light source. For example,
the angle of the solar panel modules 110 can be selected based on
the latitude of the location where the solar panel modules 110 are
to be installed.
[0090] FIG. 2 is a top view of the foundational components of a
system for mounting one or more solar panel modules. The view shown
in FIG. 2 is similar to that shown in FIG. 1B. The solar panel
modules have been removed from the view of FIG. 2 to more clearly
display the other components, such as the support frame 120, the
support strut assembly 130, and the foundational members 140. As
shown, the foundational members 140a-140c are each in contact with
the ground. The foundational members 140 are arranged in a
triangular configuration. The foundational member 140a is located
beneath the front portion of the of the module mount assembly,
while the other two foundational members 140b and 140c are located
beneath either side and toward the rear of the module mount
assembly. In some implementations, the rear two foundational
members 140b and 140c are positioned to provide support through the
support strut assembly 130 at or near the Airy points of the
structure made up of the support frame 120 and the modules 110.
Airy points are defined as the two points that are equidistant from
the center of a member and separated by a distance of 1/ {square
root over (3)} times the length of the member, or approximately 5/9
the length of the member. In some implementations, the foundational
members 140 can be arranged differently (e.g., the module mount
assembly can be supported by two front foundational members and one
rear foundational member).
[0091] The three point configuration of foundational members 140
provides strong support for the module mount assembly 100 and
allows for easily expandable installation of module mount
assemblies. For example, while each individual module mount
assembly 100 can support 12 solar panel modules 110 as discussed
above in connection with FIG. 1A, an installation site may be a
large parcel of land with sufficient area for many module mount
assemblies. If a second module mount assembly is desired at an
installation site, the two rear foundational members 140b and 140c
can be shared with the second module mount assembly and the second
module mount assembly can be installed adjacent to the first module
mount assembly. Thus, a first module mount assembly requires three
foundational members, but each additional module mount assembly
requires only an additional two foundational members. For an
arbitrarily large number of module mount assemblies, only two
foundational members are required per module mount assembly.
[0092] Although a three point foundation configuration is shown, in
some embodiments, more or fewer support points may be used (e.g.,
one, two, four, five, or more support points).
[0093] FIG. 3A is a helical pile 300 that can be used as any of the
foundational members 140 of FIG. 2. The helical pile 300 can
include an elongated shaft 302 and helical platforms 304. In some
implementations, the elongated shaft 302 can have a sharp point at
its bottom end to facilitate driving the helical pile into the
ground. A portion of the helical pile 300 can be driven into the
ground providing support for the other components in the
system.
[0094] FIG. 3B is a cross sectional view of an I-beam pile 310 that
can be used as any of the foundational members 140 of FIG. 2. The
I-beam pile 310 includes two thin rectangular outer members 312
coupled to a third rectangular inner member 314. The I-beam pile
310 can be driven into the ground, for example using a hydraulic
pile driver, and the exposed portion can be used to support the
other components of the solar panel module mount assembly.
[0095] FIG. 3C is an earth screw 320 that can be used as any of the
foundational members 140 of FIG. 2. The earth screw 320 has an
elongated shaft 322, a threaded section 324, and a platform 326.
The earth screw 320 can be screwed into the ground and the platform
326 can support the other components of the system.
[0096] FIG. 4A is a support strut assembly 400 that can be used to
support an array of solar panel modules. The support strut assembly
400 consists of a series of structural members called struts, which
rest atop the foundational members discussed in connection with
FIGS. 3A-3C. A front support structure 402 includes two struts
joined at their base on the front foundational member 140a. The
support strut assembly 400 also includes two side support
structures 404a and 404b, each of which consists of two struts
joined at their base and resting on top of the two rear
foundational members 140b and 140c, respectively. In some
implementations, the support strut assembly 400 can include a cross
brace 406 extending from the base of side support structure 404b to
the top of side support structure 404a. In its final configuration,
the front support structure 402 and the side support structures
404a and 404b of support strut assembly 400 are mechanically
coupled to support an array of solar panels. The points 408a-408d
are coincident with a plane on which an array of solar panel
modules or a frame can be secured (e.g., a plane defined by any
three points selected from points 408a-408d). FIGS. 4B, 4C, and 4D
depict top, rear, and side views of the support strut assembly 400,
respectively. For simplicity, the support strut assembly of FIGS.
4B-4D does not include the front foundational member 140a or the
rear foundational members 140b and 140c. As discussed above, the
angle of the plane defined by points 408a-408d can be selected to
maximize exposure of a solar panel array to the sun or another
light source. The angles and/or lengths of the struts in support
strut assembly 400 are adjustable such that the desired position
and orientation for the array of solar panel modules can be easily
achieved despite uneven terrain surface at the installation site.
The mechanisms for adjustment are described further below.
[0097] FIG. 5 depicts a strut 500 that can be used as any of the
structural elements of the support strut assembly 400 shown in
FIGS. 4A-4D. The strut 500 includes a central support tube 502 and
two threaded rods 504a and 504b. The support tube 502 is a hollow
member which can include threaded inserts. The threaded inserts
couple to the threads on the threaded rods 504a and 504b. Each
threaded rod 504a and 504b also includes a ball end 506 for
mechanically joining to the other components of the system, such as
the foundational components described in connection with FIGS.
3A-3C and the support frame described in connection with FIG. 2. In
some implementations, rod 504a has right-hand threads and rod 504b
has left-hand threads. The length of the strut 500 can therefore be
adjusted by rotating the support tube 502 while the rods 504a and
504b remain in a fixed orientation. For example, rotating support
tube 502 in one direction will cause the rods 504a and 504b to be
drawn into the support tube 502, thus shortening the overall length
of the strut 500. Rotating the support tube 502 in the opposite
direction will cause the threaded rods 504a and 504b to extend
outward from the support tube 502, which will increase the overall
length of the strut 500. In some implementations, the threads on
the support tube 502 and the threaded rods 504a and 504b are
configured such that a full rotation of the support tube 502
results in an increase or decrease of about 0.2 inches in the
overall length of the strut 500. In some implementations, the strut
500 can also include a lock nut 508. After the strut 500 has been
adjusted to its desired size, the lock nut 508 can be tightened to
prevent the support tube 502 from rotating with respect to the
threaded rods 504a and 504b, thus maintaining the desired length of
the strut 500.
[0098] FIGS. 6A-6D depict various implementations of kinematic
mounts for joining the struts to the other components of the
system. For example, FIG. 6A is a three support strut kinematic
mount 600 that can be used to join up to three struts to a single
pile. In one implementation, the three support strut kinematic
mount 600 can be used as the connection point between the rear
support structure 140c, the side support structure 404b, and the
cross brace 406 of FIG. 4A. An I-beam pile, similar to the I-beam
pile 310 of FIG. 3B is shown in FIG. 6A. However, any other type of
pile could be used, such as the helical pile 300 of FIG. 3A or the
earth screw 320 of FIG. 3C.
[0099] The three support strut kinematic mount 600 includes a pile
connection 602. The pile connection can be mechanically fastened to
the pile, for example using bolts 604. In some implementations, the
pile connection 602 provides an electrical path to ground between
the support strut assembly and the pile 310. For example, in some
embodiments, the pile connection may be a pinch type connection
that grasps the pile 310.
[0100] The kinematic mount 600 also includes a plate 606 coupled to
the pile connection 602. As shown in the figure, the plate 606 can
be aligned at an angle relative to the pile connection 602. The
plate 606 has three conical seats 608 into which the ball end 506
of a strut 500 can be partially inserted (see conical seat 608 of
FIG. 6B). The kinematic mount 600 also includes a clamp 610. The
clamp 610 can be fastened to the plate 606 with a bolt 612, such
that the ball end 506 is secured between the plate 606 and the
clamp 610. In some implementations, the bolt 612 is a captive bolt
that is preinstalled on the clamp 610. The clamp also includes
chamfered slots 614 which fit around the ball end 506. The shape of
the chamfered slot 614 and the conical seat 608 allow the ball end
506 to rotate freely so that the angle of the strut 500 can be
modified, while maintaining the connection between the ball end 506
and the pile 310. The freedom of rotation provided by the kinematic
mount 600, combined with the adjustable length of the struts 500
described in connection with FIG. 5, allow the support strut
assembly 400 to be adaptable to uneven ground at the installation
site. Note that, in some embodiments, the use of the conical seat
608 in combination with the chamfered slots 614 allows the
kinematic mount to be assembled easily without the need for careful
alignment or elements machined to tight tolerances.
[0101] FIG. 6B depicts a two support strut kinematic mount 620 and
FIG. 6C depicts a single support strut kinematic mount 630. The
components of the kinematic mount 620 and 630 are similar to the
components described above in connection with the three support
strut kinematic mount 600 of FIG. 6A. For example, the kinematic
mount 620 and 630 each have a pile connection 602, a plate 606 with
conical seats 608, and a clamp 610. The distinguishing features are
the number of cutouts 608 and the shape of the clamp 610. In one
implementation, the two support strut kinematic mount 620 can be
used as the connection point between the rear support structure
140b and the side support structure 404a of FIG. 4A. The single
support strut kinematic mount 630 can be used as the connection
point between the front structural support member 140a and the side
support structure 402 of FIG. 4A.
[0102] FIG. 6D illustrates another implementation of a strut
kinematic mount 640 that can be used to join a ball end 506 of a
strut 500 to a frame, such as the support frame 120 shown in FIG.
1. The kinematic mount 640 includes many of the same components as
kinematic mount 610, 620, and 630, including the plate 606 with
conical seats 608, and a clamp 610. However, because the kinematic
mount 640 is mounted directly to the support frame 620 rather than
to a pile, it does not include a pile connection.
[0103] In some implementations, the kinematic mount 600, 620, 630,
and 640 described above are configured to substantially eliminate
moment loads on the struts 500 used in support strut assembly 400.
The struts 500 therefore have to support only tension and
compression forces when the strut assembly 400 is installed. This
design allows the struts 500 to be manufactured with a
significantly smaller cross sectional area, relative to the size
that would be required if the struts 500 were also exposed to
significant moment loads.
[0104] In some embodiments, e.g., as described above, the strut
assembly 400 includes six degrees of freedom (e.g., corresponding
to one length adjustment for each of the struts 500). This
arrangement is particularly advantageous in that it may allow for
substantial elimination of moment loads 500 on all struts in the
assembly 400. However, is some embodiments, e.g., where some moment
loads may be acceptable, fewer degrees of freedom may be used.
[0105] FIG. 7 illustrates a support strut assembly (SSA) spacer
frame 700 for supporting an array of solar panel modules. The SSA
spacer frame 700 includes many of the essential components of the
support strut assembly 400 of FIGS. 4A-4D, including the front
support structure 402 and the side support structures 404a and
404b, each of which can include two struts 500. In some
implementations, the SSA spacer frame 700 can also include a cross
brace similar to cross brace 406 of FIG. 4A, although such a cross
brace is not depicted in FIG. 7. The SSA spacer frame can be
mounted on foundational members, such as the foundational members
140a-140c of FIG. 4.
[0106] The SSA spacer frame also includes a sub-frame 710. The
sub-frame 710 is a rectangular arrangement of four structural
members having substantially the same size as the support frame 120
of FIG. 1A. During installation, a ground crew can use the
sub-frame 710 to easily align the SSA spacer frame on uneven
ground, by aligning the sub-frame exactly as the array of solar
panel modules is to be aligned. In some implementations, the SSA
spacer frame 700 weighs only about 50 pounds. In contrast, the
support frame 120 can weigh several hundred pounds. The SSA spacer
frame 700 therefore makes it safe for the ground crew to align and
install the SSA spacer frame 700 without the use of heavy lifting
equipment, even on an irregular ground surface.
[0107] In some implementations, the structural components of the
SSA spacer frame have an adjustable length to accommodate
installation on an uneven surface. For example, the struts 500 of
FIG. 5 can be used as the structural members of the SSA spacer
frame 700, and the joints 610, 620, 630, and 640 of FIGS. 6A-6D can
be used to join the structural members. The structural members can
arrive at the installation site with pre-defined lengths, in order
to minimize the amount of adjustment performed by the ground crew
during installation.
[0108] FIG. 8A depicts a top view of a module frame 800 configured
for installation and use with a solar panel module. For example,
the module frame 800 could be used as the module frame 120 of FIG.
1A. The purpose of the module frame 800 is to support an array of
solar panel modules in a fixed orientation. As discussed above, the
module frame 800 can be mounted onto the support strut assembly 400
or the SSA spacer frame 700. In some implementations, the module
frame 800 is connected to the support strut assembly 400 by a joint
such as the joint 640 of FIG. 6D.
[0109] The module frame 800 includes a plurality of spars 810 and
two purlins 820. In some implementations, the purlins 820 are
positioned to support the Airy points of the spars 810, as
described above in connection with the foundational structures of
FIG. 2. The intersection of each spar 800 and each purlin 820
includes a hinge 830. As shown in FIG. 8A, the hinges 830 are in an
open configuration for installation, which allows a portion of each
spar 810 to extend outward from each purlin 820, maximizing the
length of the spars 810 and providing the largest possible surface
area for the module frame 800 to support an array of solar
panels.
[0110] FIG. 8B depicts a top view of the module frame 800
configured for shipment. In this configuration, the hinges 830 are
in a closed position, rotated (e.g., through 90 degrees) from the
open position shown in FIG. 8A. The portion of each spar 810 that
extends beyond the purlins 820 during installation is thus
redirected to lie adjacent to the purlins 820. When stowed for
shipment in this configuration, the module frame 800 occupies a
smaller area than it would in the configuration shown in FIG. 8A.
The smaller area allows for the module frame 800 to be shipped more
efficiently. Note that in other embodiments, other types of hinged
members may be used to allow the overall size of the module frame
800 to be reduced for shipment.
[0111] FIG. 9A shows a module frame 900 configured for
installation. For example, the module frame 900 could be used as
the module frame 120 of FIG. 1A. The purpose of the module frame
900 is to support an array of solar panel modules in a fixed
orientation. As discussed above, the module frame 900 can be
mounted onto the support strut assembly 400 or the SSA spacer frame
700. In some implementations, the module frame 900 is connected to
the support strut assembly 400 or the SSA spacer frame 700 by a
joint such as the joint 640 of FIG. 6D.
[0112] The module frame 900 includes a plurality of spars, such as
the spar 910, which has three pieces 910a, 910b, and 910c. The
module frame 900 also includes two purlins 920. In some
implementations, the purlins 920 are positioned to support the Airy
points of the spars 910, as described above in connection with the
foundational structures of FIG. 2. The pieces 910a-c of the spars
910 have hollow cross sections, and the dimensions of the outer
pieces 910a and 910c are slightly larger than the dimensions of the
inner piece 910b, such that the inner piece 910b can slide inside
the outer pieces 910a and 910c. In some implementations, the spars
910 have circular, C-shaped, U-shaped, or any other suitable cross
sections. As shown in FIG. 9A, the outer pieces 910a and 910c can
be arranged to extend outward beyond the purlins 920, maximizing
the length of the spars 910 and providing the largest possible
surface area for the module frame 900 to support an array of solar
panels.
[0113] FIG. 9B depicts a top view of the module frame 900
configured for shipment. In this configuration, the inner piece
910b slides within the outer pieces 910a and 910c of the spars 910
decreasing the overall length of the spars 910. When stowed for
shipment in this configuration, the module frame 900 occupies a
smaller area than it would in the configuration shown in FIG. 9A.
The smaller area allows for the module frame 900 to be shipped more
efficiently.
[0114] FIG. 9C shows a module frame 930 configured for
installation. For example, the module frame 930 could be used as
the module frame 120 of FIG. 1A. The purpose of the module frame
930 is to support an array of solar panel modules in a fixed
orientation. As discussed above, the module frame 930 can be
mounted onto the support strut assembly 400 or the SSA spacer frame
700. In some implementations, the module frame 930 is connected to
the support strut assembly 400 by a joint such as the joint 640 of
FIG. 6D.
[0115] The module frame 930 includes a plurality of spars, such as
the spar 940, which has three pieces 940a, 940b, and 940c. The
module frame 930 also includes two purlins 950. In some
implementations, the purlins 950 are positioned to support the Airy
points of the spars 940, as described above in connection with the
foundational structures of FIG. 2. The pieces 940a-c of the spars
940 have hollow cross sections, and the dimensions of the outer
pieces 940a and 940c are slightly smaller than the dimensions of
the inner piece 940b, such that the outer pieces 940a and 940c can
slide inside the inner piece 940b. In some implementations, the
spars 940 have circular, C-shaped, or U-shaped cross sections. As
shown in FIG. 9C, the outer pieces 940a and 940c can be arranged to
extend outward beyond the purlins 950, maximizing the length of the
spars 940 and providing the largest possible surface area for the
module frame 930 to support an array of solar panels.
[0116] FIG. 9D depicts a top view of the module frame 930
configured for shipment. In this configuration, the outer pieces
940a and 940c slide into the inner piece 940b of the spars 940,
decreasing the overall length of the spars 940. The purlins 950
remain in a fixed position. When stowed for shipment in this
configuration, the module frame 930 occupies a smaller area than it
would in the configuration shown in FIG. 9C. The smaller area
allows for the module frame 930 to be shipped more efficiently.
[0117] FIG. 10A depicts a module frame 1000. The module frame 1000
could be used as the module frame 120 of FIG. 1A. The purpose of
the module frame 1000 is to support an array of solar panel modules
in a fixed orientation. As discussed above, the module frame 1000
can be mounted onto the support strut assembly 400 or the SSA
spacer frame 700. In some implementations, the module frame 1000 is
connected to the support strut assembly 400 by a joint such as the
joint 640 of FIG. 6D. The module frame 1000 includes spars 1010 and
purlins 1020.
[0118] FIG. 10B depicts an enlarged view of the intersection of a
spar 1010 and a purlin 1020 of FIG. 10A. The spar 1010 and purlin
1020 are nested, such that the spar 1010 passes directly through
the purlin 1020. This is in contrast with the typical way in which
spars and purlins are stacked on top of each other. The nested
configuration of the spar 1010 and purlin 1020 of FIG. 10B reduces
the total height of the module frame 1000, which can result in more
efficient shipping of large quantities of module frames 1000. In
addition, the nested configuration allows both flanges of the spar
1010 to be supported by the purlin 1020, resulting in a more rigid
module frame 1000. The nested configuration shown in FIGS. 10A and
10B could be used in connection with other features described
above, such as the module frames discusses in connection with FIGS.
8A-B and 9A-B.
[0119] FIG. 11A depicts a perspective view of an underclamp 1100
for securing a solar panel module to a module frame, such as the
module frame 120 of FIG. 1A. The underclamp 1100 includes a module
slot 1110 located at a top portion of the underclamp 1100 and two
frame slots 1120 located beneath the module slot. Threaded cutouts
1130 extend through each of the frame slots 1120 and into the
module slot 1110. Bolts 1140 are mechanically coupled to the
threaded cutouts 1130.
[0120] FIG. 11B depicts the underclamp 1100 installed to join a
solar panel module 1150 and a module frame. The module frame
includes a spar 1160. As shown in FIG. 11B, a flange on the solar
panel module 1150 can be inserted into the module slot 1110, and a
flange of the spar 1160 can be inserted into the frame slot 1120.
Both of the bolts 1140 can then be tightened to secure the solar
panel module 1150 and the module frame in place.
[0121] As discussed above, the solar panel module 1150 and the spar
1160 can be made of an electrically conductive material with an
outer coating, such as an anodized coating or a galvanized coating.
In some implementations, the underclamp 1100 and the bolts 1140 can
be made of a conductive material, such as stainless steel or
aluminum. The bolts 1140 can pierce the coatings on the solar panel
module 1150 and the spar 1160 as they are tightened, such that all
of the components of the system are electrically connected. An
electrical connection to ground can then be attached to any of the
system components to reduce the risk of electrical shock to workers
who install or maintain the solar panel module 1150, and also to
protect the electrical components of the solar panel module 1150.
In some implementations, the bolts 1140 can be tightened so that
they pass completely through either or both of the spar 1160 and
the solar panel module 1150.
[0122] FIGS. 12A and 12B show a side view and a perspective view,
respectively, of an overclamp 1200 for securing a solar panel
module to a module frame, such as the module frame 120 of FIG. 1A.
The overclamp 1200 includes a flange 1210 and a U-shaped member
1220 mechanically coupled by a bolt 1230. A solar panel module 1240
can be secured between a bottom edge of the flange 1210 and a top
surface of the U-shaped member 1220 by loosening or tightening the
bolt 1230. A spar 1250 of a module frame can be secured within the
U-shaped member 1220, as shown in FIG. 12A.
[0123] In some implementations, the U-shaped member 1220 is made
from a rigid material and the spar 1250 must slide through the
opening in the U-shaped member 1220. In other implementations, the
U-shaped member 1220 is made from a flexible material and includes
angled teeth 1260, allowing the U-shaped member 1220 to flex over
the width of the spar 1250 and snap into place around the spar
1250. In yet another implementation, the vertical sides of the
U-shaped member 1220 can be coupled to the top surface of the
U-shaped member 1220 by hinges, which can open and close around the
spar 1250. While the spar 1250 is shown with a square cross section
in FIGS. 12A and 12B, other shapes can also be used for the spar
1250. In instances where another shape is used for the spar 1250,
the shape of the U-shaped member can be varied to match the shape
of the spar 1250, so that the spar 1250 can be held securely in
place.
[0124] FIG. 13A depicts a system 1300 for automating a portion of
the installation process for an array of solar panel modules. The
system includes an excavator 1310, a hexapod 1320, and a survey
station 1330. Foundational supports, such as the foundational
supports 140 of FIG. 1A, can be preinstalled by a ground crew. A
stack of module frames, such as module frames 120, can be placed
next to the excavator 1310 or can be stacked on a trailer attached
to the excavator 1310.
[0125] The hexapod 1320 can be configured to lift a single module
frame 120 from the stack of module frames 120. The frame 120 can
then be roughly positioned via the hydraulic arm of the excavator
1310. In some implementations, the frame 120 can be positioned
within about one foot of its final location by the excavator 1310.
The survey station 1330 can then determine the current rough
position of the frame 120 and the more accurate position required
for installation. In some implementations, the hexapod 1320 can
also include position sensors to help determine the position of the
frame 120. These positions can be transmitted from the survey
station 1330 to the hexapod 1320.
[0126] In some embodiments, the survey station may determine the
position of the frame 120 very accurately, e.g., with an accuracy
of 1 m or less, 0.1 m or less, 0.01 m or less, 0.001 m or less,
0.0001 meters or less, 0.00001 m or less, 0.000001 m or less,
0.0000001 m or less, e.g., in the range of 0.1 mm to 10 cm or any
subrange thereof. In some embodiments, the survey station may
accurately determine the orientation of the frame. For example, in
some embodiments, the survey station may determine each of the
roll, pitch and yaw of the frame with an accuracy of at least 5.0
degrees, 1.0 degree, 0.1 degrees, 0.01 degrees, 0.001 degrees,
0.0001 degrees or less, e.g., in the range of 0.0001 degrees to 5
degrees, or any subrange thereof.
[0127] In various embodiments, the survey station may be a total
survey station of the type know in the art, e.g., the TPS line of
survey stations available from Leica Geosystems
(http://www.leica-geosystems.com).
[0128] In some embodiments, the total station is an
electronic/optical instrument that includes an electronic
theodolite (transit) integrated with an electronic distance meter
(EDM) to determine the position and orientation of an object
relative to the instrument, or some other reference point. In some
embodiments, a target, e.g., a reflective target such as a prism
cube may be attached to the hexapod to aid in detecting the
position of the frame 120. Robotic total stations allow the
operator to control the instrument from a distance via remote
control.
[0129] In some embodiments, the position information may include
the position of the center of mass of the frame 120 in space (e.g.,
its x, y, and z spatial coordinates in a rectilinear coordinate
system) along with the roll, pitch and yaw of the frame.
Advantageously, these six degrees of freedom fully define the
position and orientation of the frame in space relative to a
reference point (e.g., the survey station). In other embodiments,
alternative coordinate and orientation system may be used. In some
embodiments, e.g., in applications where the precise positioning of
the frame 120 is not critical, position information including fewer
than six degrees of freedom may be used.
[0130] As shown in FIG. 13B, the hexapod 1320 has six hydraulic
legs 1340. A control system can command the legs 1340 to actuate,
precisely positioning the frame 120 for installation. In some
implementations, the hexapod 1320 receives power (e.g., electrical
or hydraulic power) from the excavator 1310. When the frame 120 has
been accurately positioned, a ground crew can perform installation
of the support strut assembly 400 of FIGS. 4A-4D. Because the frame
120 is held securely in its final location, the installation
procedure performed by the ground crew is greatly simplified. For
example, the ground crew can see exactly where the joints of the
support strut assembly 400 must be positioned, and can adjust the
lengths and angles of the struts accordingly. Furthermore, because
the relatively heavy module frame is held in place by the hexapod
1320, the ground crew can install the support strut assembly 400
and attach it to the module frame 120 without any special heavy
lifting equipment.
[0131] Although in the examples above, a hexapod 1320 was used to
position the frame 120, in other embodiments, other positioning
devices may be used, e.g., an articulated robotic arm.
[0132] FIG. 14 is a method 1400 for automating the installation of
an array of solar panel modules. The method includes the step of
installing foundational members (BLOCK 1410). In instances where a
plurality of solar panel modules are to be installed, the
foundational members for all of the solar panel module can be
installed at once. For example, FIG. 13A depicts rows of foundation
members 140 that have been preinstalled. As described above in
connection with FIG. 2, the foundational members can be installed
in a triangular configuration, such that the rear foundational
members will support the rear two Airy points of each solar panel
module. In some implementations, the foundational members can be
any of the structures shown in FIGS. 3A-3C, such as the helical
pile 300, the I-beam 310, or the earth screw 320.
[0133] The method 1400 includes the step of positioning a module
frame using the hexapod (BLOCK 1420). As described above in
connection with FIG. 14, a module frame can be picked up by a
hexapod and roughly positioned by an excavator. The hexapod can
then communicate with a survey station to more accurately position
the frame for installation.
[0134] The method 1400 includes the step of installing the support
strut assembly (BLOCK 1430), such as the support strut assembly 400
of FIGS. 4A-4D. The support strut assembly can have adjustable
struts and joints to facilitate installation on uneven terrain. A
ground crew can connect the support strut assembly to the
foundational structures that were previously installed (BLOCK
1410). The lengths of the struts and angles of the joints can then
be adjusted by the ground crew such that the upper section of the
support strut assembly aligns with the module frame, which is held
in its correct position by the hexapod.
[0135] The method 1400 includes the step of installing a solar
panel module (BLOCK 1440). The support structure, including the
foundation, the support strut assembly, and the module frame, has
already been installed. A ground crew can thus install a solar
panel module onto the support structure. In some implementations,
the solar panel module is installed using one or both of the
underclamp 1100 of FIGS. 11A and 11B and the overclamp 1200 of
FIGS. 12A and 12B.
[0136] The method 1400 also includes the step of moving the hexapod
to a subsequent foundation (BLOCK 1450). If there are solar panel
modules or frames remaining to be installed, the excavator can be
moved to the next foundation. In some implementations, the
excavator can tow a trailer on which additional module frames are
stacked. The method 1400 can then return to BLOCK 1420 to complete
the installation for the next foundation.
[0137] In some implementations, the steps of the method 1400 can be
performed in a different order than is presented in FIG. 14. For
example, it may not be necessary to install a solar panel module
(BLOCK 1440) before moving the hexapod to the next foundation
(BLOCK 1450). The steps requiring use of the hexapod may be
performed in sequence before any solar panel modules are installed
(BLOCK 1440), and manual installation steps can be performed
subsequently.
[0138] FIG. 15 is a method for manually installing an array of
solar panel modules. The method 1500 includes the step of
installing foundational members (BLOCK 1510). In instances where a
plurality of solar panel modules is to be installed, the
foundational members for all of the solar panel modules can be
installed at once. As described above in connection with FIG. 2,
the foundational members can be installed in a triangular
configuration, such that the rear foundational members will support
the rear two Airy points of each solar panel module. In some
implementations, the foundational members can be any of the
structures shown in FIGS. 3A-3C, such as the helical pile 300, the
I-beam 310, or the earth screw 320.
[0139] The method 1500 includes the step of installing the support
strut assembly (BLOCK 1520), such as the support strut assembly 400
of FIGS. 4A-4D. The support strut assembly can have adjustable
struts and joints to facilitate installation on uneven terrain. A
ground crew can connect the support strut assembly to the
foundational structures that were previously installed (BLOCK
1510). The lengths of the struts and angles of the joints can then
be adjusted by the ground crew such that the upper section of the
support strut assembly defines a plane on which a module frame can
subsequently be installed.
[0140] The method 1500 includes the step of installing a module
frame (BLOCK 1530). Having already installed the support strut
assembly in its correct orientation (BLOCK 1520), the module frame
can be installed onto a top portion of the support strut
assembly.
[0141] In some implementations, the steps of the method 1500 can be
performed in a different order than is presented in FIG. 15. For
example, it may not be more efficient to install the foundational
members (BLOCK 1510) for a plurality of module mount assemblies,
before installing any of the strut assemblies (BLOCK 1520), frames
(BLOCK 1530), or solar panel modules (BLOCK 1540).
[0142] The method 1500 also includes the step of installing a solar
panel module (BLOCK 1540). The support structure, including the
foundation, the support strut assembly, and the module frame, has
already been installed. The ground crew can thus install a solar
panel module onto the support structure. In some implementations,
the solar panel module is installed using one or both of the
underclamp 1100 of FIGS. 11A and 11B and the overclamp 1200 of
FIGS. 12A and 12B.
[0143] In some implementations, alignment of the components of the
solar panel array may be adjusted at various points in the method
1500. For example, the method 1500 can be performed as described
above, and a electronic or optical positioning equipment can be
used to determine whether the array of solar panels is properly
aligned. If a misalignment is detected, the lengths of some or all
of the struts can be adjusted to compensate such that the array is
correctly aligned.
[0144] In some other implementations, positioning equipment can be
used to determine the locations of the foundational members in
three-dimensional space immediately after they are installed.
Knowledge of the locations of the locations of the foundational
members, combined with knowledge of the desired orientation of the
solar panel array, can be used to compute the necessary adjustments
for the struts and other components. The struts can then be
adjusted accordingly, either before or after they are installed on
the foundational members. Alignment techniques such as those
described above can help to maintain proper orientation of the
solar panel array, particularly when the array is to be installed
on an uneven surface.
[0145] FIG. 16A is a perspective view of a strut-pile connection
1600, according to an illustrative implementation. The connection
1600 can be used to join components, such as the helical pile 300
of FIG. 3A, the I-beam pile 310 of FIG. 3B, or the earth screw 320
of FIG. 3C with struts, such as the struts of the strut support
assembly 400 shown in FIG. 4A. In some implementations, the piles
or earth screws can serve the function of the foundational members
140 of FIG. 1A.
[0146] As shown in FIG. 16A, a strut, such as strut 1605, can
include a hollow tube 1610, a threaded rod 1620 having a spherical
end 1625, and a spherical washer 1630. Additional features and
functionality of the strut 1605 are described in connection with
FIGS. 16B-16E below. The I-beam pile 310 can include keyhole
cutouts such as the keyhole cutout 1640 into which a portion of the
strut 1605 can be inserted and secured. Any number of keyhole
cutouts 1640 can be present on the various surfaces of the I-beam
pile 310, allowing multiple struts 1605 to be attached to the pile
310. The location and orientation of the keyhole cutouts 1640 can
be adjusted to allow for differing orientations of the struts 1605.
Although an I-beam pile 310 is shown in FIG. 16A, a pile of any
shape could be substituted.
[0147] FIG. 16B is an exploded view of a strut 1605 for use in the
strut-pile connection 1600 of FIG. 16A, according to an
illustrative implementation. The strut 1605 includes a hollow tube
1610, a threaded rod 1620 having a spherical end 1625, a spherical
washer 1630 having a cylindrical seat 1635, a threaded insert 1645,
screws 1650, a nut 1655, a barrel nut 1660, and a bolt 1665 having
a flange 1670. When the strut 1605 is assembled, the threaded
insert 1645 is inserted into the hollow tube 1610 and secured with
the screws 1650. The threaded rod 1620 is inserted through both the
nut 1655 and the threaded insert 1645. The length of the strut 1605
can be adjusted by rotating the threaded rod 1620 clockwise or
counterclockwise within the threaded insert 1645. In some
implementations, some of the threads on the threaded rod 1620 can
be modified after it has been inserted into the nut 1655 and the
threaded insert 1645. For example, the structure of the threads at
the end of the threaded rod 1620 opposite the spherical end 1625
can be altered in order to prevent the threaded rod 1620 from
passing back through the threaded insert 1645. This can help to
increase safety by preventing the assembled strut 1605 from
separating into two pieces after assembly, while still for the
length of the strut 1605 to be adjusted.
[0148] The spherical end 1625 of the threaded rod 1620 includes a
cutout into which the barrel nut 1660 is inserted. The bowl-shaped
surface of the spherical washer 1630 is then placed in contact with
the spherical end 1625 of the threaded rod 1620, and the bolt 1665
is inserted through the spherical washer 1630 and through the
barrel nut 1660. The flange 1670 of the bolt 1665, as well as the
cylindrical seat 1635 of the spherical washer 1630, help to secure
the strut 1605 to a pile in the strut-pile connection 1600.
[0149] FIG. 16C is a perspective view of a strut pile connection
1600 prior to installation of the strut 1605, according to an
illustrative implementation. The components of the strut 1605 are
assembled as discussed above in connection with FIG. 16B. The bolt
1665 is only partially tightened, so that a gap remains between the
flange 1670 and the spherical washer 1630. The bolt 1665 is then
inserted into the keyhole cutout 1640 of the pile 310.
[0150] The keyhole cutout 1640 includes a larger upper region and a
smaller lower region. The diameter of the large upper region is
greater than the diameter of the flange 1670, but smaller than the
diameter of the spherical washer 1630, which allows the bolt 1665
to pass through the larger upper region of the keyhole cutout 1640
but prevents the spherical washer 1630 from also passing through.
The entire strut 1605 is then moved down and seated into the
smaller lower region of the keyhole cutout 1640, which has a
diameter smaller than the diameters of both the spherical washer
1630 and the flange 1670. The bolt 1665 can then be tightened
completely, securing the strut 1605 to the pile 310. The spherical
end 1625 of the threaded rod 1620 can move freely within the
spherical washer 1630, allowing the strut 1605 to move while
remaining secured to the pile 310.
[0151] An advantage of the strut-pile connection 1600 is that the
strut 1605 can be delivered to the installation site fully
assembled as described in connection with FIG. 16B. Field
technicians therefore do not have to be concerned with obtaining
loose fasteners, such as the bolt 1665, in order to secure the
strut 1605 to the pile 310. The installation process is therefore
simplified and the risk of misplacing small mechanical fasteners at
the installation site is minimized.
[0152] FIG. 16D is an enlarged view of the strut-pile connection
1600, according to an illustrative implementation. Two struts,
1605a and 1605b, are shown. For clarity, strut 1605b is shown
without the bolt 1665 attached. Typically, the bolt 1665 is
installed on the strut 1605b when the strut 1605 arrives at the
installation site, as described above.
[0153] As can be seen on strut 1605b, the cylindrical seat 1635 of
the spherical washer 1630 can be inserted into the smaller lower
region of the keyhole cutout 1640. In some implementations, the
diameter of the cylindrical seat 1635 is substantially equal to the
diameter of the lower region of the keyhole cutout 1640 so that the
strut 1605b cannot move up or down within the keyhole cutout 1640.
Strut 1605a is shown in its fully installed configuration, secured
by the bolt 1665.
[0154] FIG. 16E is a perspective view of a strut-frame connection
1680, according to an illustrative implementation. For example, the
strut-frame connection 1680 can be used to secure a strut, such as
strut 1605 of FIG. 16B, to a frame, such as module frame 800 of
FIG. 8A. the strut-frame connection 1680 contains features
identical to those described in connection with the strut-pile
connection 1600 of FIG. 16A, and operates in substantially the same
manner. As shown in FIG. 16E, the frame 800 includes keyhole
cutouts 1640. The strut 1605 is assembled as described above in
connection with FIG. 16B, and is then inserted through the keyhole
cutout 1640 such that the spherical washer 1630 is seated within
the bottom portion of the keyhole cutout 1640. The bolt 1665 is
then tightened to secure the strut 1605 to the frame 800.
[0155] FIG. 17A is a side view of a midclaw 1700 for securing two
solar panel modules in an uninstalled configuration, according to
an illustrative implementation. For example, the midclaw 1700 can
be used to secure two modules, such as modules 110 of FIG. 1A, to a
frame, such as frame 800 of FIG. 8A. The midclaw 1700 includes two
flanges 1705, a midclaw bolt 1710, a rafter block 1715, and a
rafter block bolt 1720. The rafter block 1715 is mounted on top of
rafter 1717 (e.g., a portion of a frame such as frame 800 of FIG.
8A). When the rafter block 1715 is secured to the rafter 1717 with
the rafter block bolt 1720, the midclaw 1700 remains in a fixed
position, allowing a technician to correctly place the modules 110a
and 110b against the top side of the rafter block 1715, without
being concerned about the position of the claw 1700. The midclaw
bolt 1710 can then be tightened, lowering the midclaw 1700 until
the modules 110a and 110b are secured between the top of the rafter
block 1715 and the flanges 1705.
[0156] FIG. 17B is a side view of the midclaw of FIG. 17A in its
fully installed configuration, according to an illustrative
implementation. The bottom surface of rafter block 1715 is secured
flush against the rafter 1717 by the rafter block bolt 1720. The
bottom surfaces of modules 110a and 110b lie flat against the top
surface of the rafter block 1715, and the midclaw bolt 1710 has
been tightened so that the flanges 1705 secure the top surfaces of
the modules 110a and 110b.
[0157] FIG. 17C is an end view of the midclaw of FIG. 17A in its
fully installed configuration, according to an illustrative
implementation. The rafter block 1715 is mounted on top of the
rafter 1717. Note that the rafter 1717 has a hollow U-shaped
structure, and a rafter nut 1725 is secured to the bottom of the
rafter bolt 1720 and located within the rafter 1717. Thus, to
secure the rafter block 1715 to the rafter 1717, a technician can
tighten the rafter bolt 1725 until it is positioned against the
inside surface of the rafter 1717 while the rafter block 1715 is
positioned against the outside surface of the rafter 1717. As
described above, the technician can then focus on aligning the
solar panel modules rather than worrying about the position of the
midclaw 1700. For clarity, the solar panel modules are not visible
in FIG. 17C. The modules can be placed on top of the rafter block
1715, and a technician can then tighten the midclaw bolt 1710 until
the flanges 1705 contact the modules, securing the modules between
the flanges 1705 and the rafter block 1715.
[0158] FIG. 18A is a side view of an endclaw 1800 for securing a
solar panel module at the edge of a module array in an uninstalled
configuration, according to an illustrative implementation. For
example, the endclaw 1800 can be used to secure a module, such a
module 110 of FIG. 1A which does not share an edge with another
module in the array, to a frame, such as frame 800 of FIG. 8A. The
endclaw 1800 includes many features similar to those of the midclaw
1700 of FIG. 17A. For example, the endclaw 1800 includes two
flanges 1805a and 1805b, an endclaw bolt 1810, a rafter block 1815,
and a rafter block bolt 1820. Unlike the rafter block 1715 of FIG.
17A, the rafter block 1815 is asymmetrical in side view, and
includes a raised portion on one side. The raised portion includes
two grooves 1850a and 1850b.
[0159] The rafter block 1815 is mounted on top of rafter 1817
(e.g., a portion of a frame such as frame 800 of FIG. 8A). When the
rafter block 1815 is secured to the rafter 1817 with the rafter
block bolt 1820, the endclaw 1800 remains in a fixed position,
allowing a technician to correctly place the module 110 against the
top side of the rafter block 1815, without being concerned about
the position of the claw 1800. The endclaw bolt 1810 can then be
tightened, lowering the endclaw 1800 until the module 110 is
secured between the top of the rafter block 1815 and the flange
1805a. The flange 1805b is then secured against the raised portion
of the rafter block 1815 in groove 1850a. This allows the endclaw
1800 to remain level prevents the endclaw 1800 and the endclaw bolt
1810 from experiencing torsional forces. Instead, the endclaw 1800
and the endclaw bolt 1810 are subjected only to tension forces,
which helps to preserve the structural integrity of the endclaw
1800 and hold the module 110 more securely. In this example, the
flange 1805b rests against groove 1850a because groove 1850a is at
substantially the same height as the module 110. In other
implementations, the flange 1805b could be secured against the
second groove 1850b to accommodate a module of a different
height.
[0160] FIG. 18B is a side view of the endclaw of FIG. 18A in its
fully installed configuration, according to an illustrative
implementation. The bottom surface of rafter block 1815 is secured
flush against the rafter 1817 by the rafter block bolt 1820. The
bottom surfaces of module 110 lies flat against the top surface of
the rafter block 1815, and the endclaw bolt 1810 has been tightened
so that the flange 1805a secures the top surface of the modules 110
and the flange 1805b is secured in the groove 1850a.
[0161] FIG. 18C is an end view of the endclaw of FIG. 18A in its
fully installed configuration, according to an illustrative
implementation. The rafter block 1815 is mounted on top of the
rafter 1817. Note that the rafter 1817 has a hollow U-shaped
structure, and a rafter nut 1825 is secured to the bottom of the
rafter bolt 1820 and located within the rafter 1817. Thus, to
secure the rafter block 1815 to the rafter 1817, a technician can
tighten the rafter bolt 1825 until it is positioned against the
inside surface of the rafter 1817 while the rafter block 1815 is
positioned against the outside surface of the rafter 1817. As
described above, the technician can then focus on aligning the
solar panel module rather than worrying about the position of the
endclaw 1800. For clarity, the solar panel module is not visible in
FIG. 18C. The module can be placed on top of the rafter block 1815,
and a technician can then tighten the endclaw bolt 110 until the
flange 1805a contacts the module, securing the module between the
flanges 1805a and the rafter block 1815.
[0162] In some implementations, any of the structural components
described above may be used to provide a continuous electrical
connection for grounding purposes. For example, materials for
components such as struts, bolts, nuts, clamps, and other
components can be selected based on their electrical conductivity.
Electrically conductive metals, such as aluminum alloys or zinc
alloys may be used. Various implementations may include protective
coatings over electrically conductive materials. These coatings may
be electrically conductive or may be insulating materials. The
implementations discussed above may be used to create structures
that are electrically grounded even in instances where electrically
insulating coatings are used.
[0163] For example, serrations on various components may break
through an insulating coating to provide an electrical path to
ground. In one implementation, a frame such as frame 800 of FIG. 8A
may be made from an electrically conductive material coated with an
insulating material. The modules may be secured to the frame using
the midclaw of FIG. 17A or the end claw of FIG. 18A, which may
themselves be made from conductive materials. Serrations on the
flanges of the midclaw and endclaw may break through a coating on
the frame to provide an electrical connection. The electrical path
can continue through other components such as struts and piles so
that the solar panel modules are electrically connected to ground
for safety or reliability purposes.
[0164] Various examples have been given for devices, systems and
methods for mounting solar panel modules. As used herein, the term
solar panel module refers to a complete, environmentally protected
unit designed to generate power when exposed to sunlight and
comprising one or more solar cells and, optionally, optics and/or
other components (typically exclusive of a tracker). A solar cell
is a photovoltaic device that generates electricity when exposed to
light. However, some embodiments may be used for mounting solar
panel modules or arrays of solar modules, where the term solar
panel modules refers to collection of modules mechanically fasten
together, wired, and designed to provide a field-installable unit.
Various embodiments may be used to mount any other suitable devices
(e.g. mirrors, heat tubes, thermoelectric devices, optical devices,
etc.).
[0165] While various inventive embodiments have been described and
illustrated herein, those of ordinary skill in the art will readily
envision a variety of other means and/or structures for performing
the function and/or obtaining the results and/or one or more of the
advantages described herein, and each of such variations and/or
modifications is deemed to be within the scope of the inventive
embodiments described herein. More generally, those skilled in the
art will readily appreciate that all parameters, dimensions,
materials, and configurations described herein are meant to be
exemplary and that the actual parameters, dimensions, materials,
and/or configurations will depend upon the specific application or
applications for which the inventive teachings is/are used. Those
skilled in the art will recognize, or be able to ascertain using no
more than routine experimentation, many equivalents to the specific
inventive embodiments described herein. It is, therefore, to be
understood that the foregoing embodiments are presented by way of
example only and that, within the scope of the appended claims and
equivalents thereto, inventive embodiments may be practiced
otherwise than as specifically described and claimed. Inventive
embodiments of the present disclosure are directed to each
individual feature, system, article, material, kit, and/or method
described herein. In addition, any combination of two or more such
features, systems, articles, materials, kits, and/or methods, if
such features, systems, articles, materials, kits, and/or methods
are not mutually inconsistent, is included within the inventive
scope of the present disclosure.
[0166] The above-described embodiments can be implemented in any of
numerous ways. For example, the embodiments may be implemented
using hardware, software or a combination thereof. When implemented
in software, the software code can be executed on any suitable
processor or collection of processors, whether provided in a single
computer or distributed among multiple computers.
[0167] Further, it should be appreciated that a computer may be
embodied in any of a number of forms, such as a rack-mounted
computer, a desktop computer, a laptop computer, or a tablet
computer. Additionally, a computer may be embedded in a device not
generally regarded as a computer but with suitable processing
capabilities, including a Personal Digital Assistant (PDA), a smart
phone or any other suitable portable or fixed electronic
device.
[0168] Also, a computer may have one or more input and output
devices. These devices can be used, among other things, to present
a user interface. Examples of output devices that can be used to
provide a user interface include printers or display screens for
visual presentation of output and speakers or other sound
generating devices for audible presentation of output. Examples of
input devices that can be used for a user interface include
keyboards, and pointing devices, such as mice, touch pads, and
digitizing tablets. As another example, a computer may receive
input information through speech recognition or in other audible
format.
[0169] Such computers may be interconnected by one or more networks
in any suitable form, including a local area network or a wide area
network, such as an enterprise network, and intelligent network
(IN) or the Internet. Such networks may be based on any suitable
technology and may operate according to any suitable protocol and
may include wireless networks, wired networks or fiber optic
networks.
[0170] A computer employed to implement at least a portion of the
functionality described herein may comprise a memory, one or more
processing units (also referred to herein simply as "processors"),
one or more communication interfaces, one or more display units,
and one or more user input devices. The memory may comprise any
computer-readable media, and may store computer instructions (also
referred to herein as "processor-executable instructions") for
implementing the various functionalities described herein. The
processing unit(s) may be used to execute the instructions. The
communication interface(s) may be coupled to a wired or wireless
network, bus, or other communication means and may therefore allow
the computer to transmit communications to and/or receive
communications from other devices. The display unit(s) may be
provided, for example, to allow a user to view various information
in connection with execution of the instructions. The user input
device(s) may be provided, for example, to allow the user to make
manual adjustments, make selections, enter data or various other
information, and/or interact in any of a variety of manners with
the processor during execution of the instructions.
[0171] The various methods or processes outlined herein may be
coded as software that is executable on one or more processors that
employ any one of a variety of operating systems or platforms.
Additionally, such software may be written using any of a number of
suitable programming languages and/or programming or scripting
tools, and also may be compiled as executable machine language code
or intermediate code that is executed on a framework or virtual
machine.
[0172] In this respect, various inventive concepts may be embodied
as a computer readable storage medium (or multiple computer
readable storage media) (e.g., a computer memory, one or more
floppy discs, compact discs, optical discs, magnetic tapes, flash
memories, circuit configurations in Field Programmable Gate Arrays
or other semiconductor devices, or other non-transitory medium or
tangible computer storage medium) encoded with one or more programs
that, when executed on one or more computers or other processors,
perform methods that implement the various embodiments of the
invention discussed above. The computer readable medium or media
can be transportable, such that the program or programs stored
thereon can be loaded onto one or more different computers or other
processors to implement various aspects of the present invention as
discussed above.
[0173] The terms "program" or "software" are used herein in a
generic sense to refer to any type of computer code or set of
computer-executable instructions that can be employed to program a
computer or other processor to implement various aspects of
embodiments as discussed above. Additionally, it should be
appreciated that according to one aspect, one or more computer
programs that when executed perform methods of the present
invention need not reside on a single computer or processor, but
may be distributed in a modular fashion amongst a number of
different computers or processors to implement various aspects of
the present invention.
[0174] Computer-executable instructions may be in many forms, such
as program modules, executed by one or more computers or other
devices. Generally, program modules include routines, programs,
objects, components, data structures, etc. that perform particular
tasks or implement particular abstract data types. Typically the
functionality of the program modules may be combined or distributed
as desired in various embodiments.
[0175] Also, data structures may be stored in computer-readable
media in any suitable form. For simplicity of illustration, data
structures may be shown to have fields that are related through
location in the data structure. Such relationships may likewise be
achieved by assigning storage for the fields with locations in a
computer-readable medium that convey relationship between the
fields. However, any suitable mechanism may be used to establish a
relationship between information in fields of a data structure,
including through the use of pointers, tags or other mechanisms
that establish relationship between data elements.
[0176] Also, various inventive concepts may be embodied as one or
more methods, of which an example has been provided. The acts
performed as part of the method may be ordered in any suitable way.
Accordingly, embodiments may be constructed in which acts are
performed in an order different than illustrated, which may include
performing some acts simultaneously, even though shown as
sequential acts in illustrative embodiments.
[0177] All definitions, as defined and used herein, should be
understood to control over dictionary definitions, definitions in
documents incorporated by reference, and/or ordinary meanings of
the defined terms.
[0178] The indefinite articles "a" and "an," as used herein in the
specification and in the claims, unless clearly indicated to the
contrary, should be understood to mean "at least one."
[0179] The phrase "and/or," as used herein in the specification and
in the claims, should be understood to mean "either or both" of the
elements so conjoined, i.e., elements that are conjunctively
present in some cases and disjunctively present in other cases.
Multiple elements listed with "and/or" should be construed in the
same fashion, i.e., "one or more" of the elements so conjoined.
Other elements may optionally be present other than the elements
specifically identified by the "and/or" clause, whether related or
unrelated to those elements specifically identified. Thus, as a
non-limiting example, a reference to "A and/or B", when used in
conjunction with open-ended language such as "comprising" can
refer, in one embodiment, to A only (optionally including elements
other than B); in another embodiment, to B only (optionally
including elements other than A); in yet another embodiment, to
both A and B (optionally including other elements); etc.
[0180] As used herein in the specification and in the claims, "or"
should be understood to have the same meaning as "and/or" as
defined above. For example, when separating items in a list, "or"
or "and/or" shall be interpreted as being inclusive, i.e., the
inclusion of at least one, but also including more than one, of a
number or list of elements, and, optionally, additional unlisted
items. Only terms clearly indicated to the contrary, such as "only
one of" or "exactly one of," or, when used in the claims,
"consisting of," will refer to the inclusion of exactly one element
of a number or list of elements. In general, the term "or" as used
herein shall only be interpreted as indicating exclusive
alternatives (i.e. "one or the other but not both") when preceded
by terms of exclusivity, such as "either," "one of," "only one of,"
or "exactly one of." "Consisting essentially of," when used in the
claims, shall have its ordinary meaning as used in the field of
patent law.
[0181] As used herein in the specification and in the claims, the
phrase "at least one," in reference to a list of one or more
elements, should be understood to mean at least one element
selected from any one or more of the elements in the list of
elements, but not necessarily including at least one of each and
every element specifically listed within the list of elements and
not excluding any combinations of elements in the list of elements.
This definition also allows that elements may optionally be present
other than the elements specifically identified within the list of
elements to which the phrase "at least one" refers, whether related
or unrelated to those elements specifically identified. Thus, as a
non-limiting example, "at least one of A and B" (or, equivalently,
"at least one of A or B," or, equivalently "at least one of A
and/or B") can refer, in one embodiment, to at least one,
optionally including more than one, A, with no B present (and
optionally including elements other than B); in another embodiment,
to at least one, optionally including more than one, B, with no A
present (and optionally including elements other than A); in yet
another embodiment, to at least one, optionally including more than
one, A, and at least one, optionally including more than one, B
(and optionally including other elements); etc.
[0182] In the claims, as well as in the specification above, all
transitional phrases such as "comprising," "including," "carrying,"
"having," "containing," "involving," "holding," "composed of," and
the like are to be understood to be open-ended, i.e., to mean
including but not limited to. Only the transitional phrases
"consisting of" and "consisting essentially of" shall be closed or
semi-closed transitional phrases, respectively, as set forth in the
United States Patent Office Manual of Patent Examining Procedures,
Section 2111.03
* * * * *
References