WO2017007736A1

WO2017007736A1 - Ballasted mount for pv panels

Info

Publication number: WO2017007736A1
Application number: PCT/US2016/040914
Authority: WO
Inventors: Jan Kunczynski
Original assignee: Jan Kunczynski
Priority date: 2015-07-04
Filing date: 2016-07-03
Publication date: 2017-01-12

Abstract

The present invention provides a cost-effective and easily installed rack for mounting a photovoltaic panel using ballast to anchor position. Innovative features include light-weight construction with metal sheeting and attachment mechanisms that avoid the drilling of holes. The predictable 80% weight reduction due to efficient design potentially avoids structural reinforcement at roof locations.

Description

TITLE: BALLASTED MOUNT FOR PV PANELS

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a PCT application claiming priority to U.S. Provisional Application

62/188,648, filed 4 July 2015, which is incorporated herein by reference in entirety.

FIELD OF THE INVENTION

This invention relates to mounting racks for photovoltaic panels, and in particular to ballast-weighted racks for photovoltaic panels.

BACKGROUND OF THE INVENTION

Photovoltaic panels, often referred to as "solar panels" or "PV panels", are rectilinear assemblies of photovoltaic cells. The panels are typically mounted in arrays on rooftops, decks or on the ground to supply electricity to an infrastructure, such as a building, or to the electrical grid. For best effect, the arrays are oriented to the sun's incident angle at any place and time, the tilt angle of the array being variable by location and also by season. The preferred angle is latitude minus 15 degrees in the summer and latitude plus 15 degrees in the winter. In times of high wind conditions, it might be useful to temporarily lower the angle. Low angle shadow effects might result in the need to change the location at certain times during the year, or even during the day.

The mounting systems of current practice often employ fasteners to anchor to the mounting surface and to the PV panel through drilled holes. Adjusting the location of the panel involves unfastening and refastening the hardware, often with new drilling required. Adjustment of angle involves the adjustment of the length of the support struts, providing such adjustment is afforded in the design, in addition to repositioning the fasteners. Of course, the location can be changed more easily with a ballast- mounted installation since the rack is anchored in that case only by weight. Some roof top installations require reinforcement of the roof to offset the combined weight of panels and supporting racks. The racks themselves may be a significant part of the overall load. It becomes critical, particularly when using ballast, to offset the weight of the racks by selecting high strength materials, minimizing cross- sections, and using shape rather than mass to add stiffness. This type of weight- efficient design is lacking in the current technology of mounting systems.

Missing in the prior art is an easily adjustable and easily movable rack system, which requires no drilling or special tools and which can be setup and repositioned within minutes. Even when the installation angle is fixed by design, there is a need for simplicity, low cost fabrication, and an efficient use of weight-to-strength-ratio.

SUMMARY OF THE INVENTION

The present invention addresses the above-mentioned technology gaps by using ballast to anchor the rack to a roof or mounting surface. One novel feature includes using clamps to attach the rack to the PV panels without drilling holes and marring the panels. Another novel feature involves shaping thin sheet metal strips to provide both structural stiffness and flex modulus in one upright supporting element. This is accomplished by brake-bending the strips to form a composite of two interlocked components, one shaped for flexibility at the ends and the other for stiffness between the ends.

It is accordingly an object of the present invention to provide a rack for a PV panel by simple and inexpensive means and materials. It is further object that the rack be easily adjustable as to inclination and location within a matter of 2 to 3 minutes. It is a further object that no drill holes are required in assembly. It is further object that assembly involve no tool other than a driver to set a clamp. It is further object that attachment to the PV panel be accomplished by clamping means. It is a further object that weight of the structural components of the rack, other than ballast, be pared to the minimum required to achieve strength. It is a further object that strength

requirements include protection from damage by wind incidence. These objects, and others to become hereinafter apparent, are embodied in a rack for adjustably mounting a photovoltaic panel to a substantially horizontal surface comprising, in a first element, a bendable member having a distal end, a proximal end, longitudinal extent and opposing channels running along the longitudinal extent at lateral edges of the bendable member. A second element comprises a stiff member inter-positioned with the opposing channels of the bendable member medially between the distal and proximal ends to leave a protrusion of the bendable member at the distal end while forming a brace between the protrusion and the proximal end. A third element comprises a ballast having sufficient weight to removably anchor the brace by placement upon a portion of the distal end protrusion bent at a first angle. A fourth element comprises a connecting member to connect with a frame element of the photovoltaic panel by means of interlock thereto while protruding therefrom in a swept boss. Lastly, a fifth element comprises at least one clamp to removably connect the brace at a selected position at at least one of the lateral edges of the bendable member in the vicinity of the proximal end with the swept boss, the connection supporting the photovoltaic panel. In the best mode configuration of the above elements, the photovoltaic panel may be braced upright at a selected angle of inclination and mounted to the substantially horizontal surface by means of the ballast and the clamp, the mounting otherwise without fasteners.

As this is not intended to be an exhaustive recitation, other embodiments may be learned from practicing the invention or may otherwise become apparent to those skilled in the art.

DESCRIPTION OF THE DRAWINGS

Various other objects, features and attendant advantages of the present invention will become fully appreciated as the same becomes better understood through the accompanying drawings and the following detailed description, in which like reference characters designate the same or similar parts throughout the several views, and wherein:

FIG. 1 is a front perspective view of an adjustable embodiment of the mounting rack of the present invention; FIG. 2 is a front perspective view of an alternative embodiment of the mounting rack; FIG. 3 is an exploded perspective view of the adjustable embodiment of FIG. 1;

FIG. 4 is a rear elevation view of the adjustable embodiment of Fig. 1 with detail callouts;

FIG. 5 is a detail view of FIG. 4 showing an attachment mechanism at the proximal end of the brace member including the connecting member;

FIG. 6 is a detail view of FIG. 4 showing attachment of the foot member to a lower frame member of the PV panel;

FIG. 7 is an exploded perspective view of the alternative embodiment of FIG. 2; FIG. 8 is a front elevation view of the alternative embodiment;

FIG. 9 is a section view taken along the line 9-9 of FIG. 8 with a detail callout;

FIG. 10 is a detail view of FIG. 9 showing an attachment mechanism at the proximal end of the brace member;

FIG. 11 a cut perspective view of the assembly of the bendable member and the stiff member;

FIG. 12 is a perspective view of the connecting member; and

FIG. 13 is a diagram illustrating various angular relationships.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring to Fig's 1 and 2, a rack 1 for adjustably mounting a photovoltaic panel 2 to a substantially horizontal surface, such as a rooftop, is comprised of a brace member 10, a means for removably anchoring 20 the brace member 10, and a means for removably attaching 30 the brace member 10 to the photovoltaic panel 2 without defacing, or otherwise altering, the panel. Preferably, a minimum of two braces is used for each panel in flanking positions with respect to the panel. With a proper design of the brace, such as that discussed herein following, the weight burden of the rack can be reduced by as much as 80 percent over a conventional commercial rack.

In the preferred embodiment, as shown in Fig's 3-6, the brace 10 is comprised of a bendable member 11 inter-positioned with a stiff member 100. The bendable member 11 has a distal end 12, a proximal end 13, longitudinal extent and opposing channels 15 (Fig. 11). The opposing channels 15 run along the longitudinal extent at lateral edges 19. The bendable member 11 is formed from a first strip 102 of sheet metal by folding the running edges of the strip inwardly to form the opposing channels 15, after which the opposing channels 15 bracket a gap 104 (Fig. 11). The bendable member 11 has at least one bend 108 near the distal end 12 forming a protrusion 14. The at least one bend 108 forms a first angle 16 between the bendable member 11 and its protrusion 14 (Fig's 3 and 13). The bend is of sufficient radius to prevent fatigue of the material when the first angle is repeatedly manipulated. In forming any bends, the opposing channels 15 are hammered flat to remove buttressing structure at the instant locale of the bend.

The stiff member 100 is formed from a second strip 103 of sheet metal by deforming it longitudinally to take up a non-linear cross-section portion 105 (Fig. 11). The nonlinear cross-section portion 105 is flanked at each running edge thereof by flanges 106. The flanges 106 are configured to slidingly interpose in the opposing channels 15 with the non-linear cross-section portion 105 protruding in a normal direction from the gap 104. The protrusion of shape adds buttressing structure to the brace 10, which prevents longitudinal flexion and thereby adds stiffness to the brace. Because the stiffness is added by shaping thin materials having compression strength, such as metal sheeting, a bracing function is achieved with minimal weight. Preferably, the non-linear cross-section portion 105 is arcuate in shape, as shown in the figures. Other cross-sectional shapes could include rectilinear, V-shaped or another geometry (not shown).

In the preferred embodiment, the means for removably anchoring 20 the brace member 11 comprises ballast 21. Ballast 21 overlays the protrusion 14 of the bendable member 11 to anchor it by applying its weight. The weight of the ballast 21 is sufficient to prevent movement of the brace, and therefore the photovoltaic panel, under environmental conditions, and particularly under conditions of high wind incidence. The protrusion 14 is preferably bent up in a hook 107 at the distal end 12 to "cup" the ballast 21 between the hook 107 and the first angle 16.

In the preferred embodiment, the means for attaching 30 the brace member 10 to the photovoltaic panel 2 comprises at least one clamp 31 connected to a connecting member 32 (Fig's 3, 5 and 12). The connecting member 32 removably attaches to an upper frame member of the photovoltaic panel 2 by clamping means. Preferably, the clamping means is by screws threaded through die-tapped holes in the connecting member 32. The connecting member 32 has an externally placed swept boss 33. The at least one clamp 31 connects the swept boss 33 to one of the lateral edges 19 of the bendable member 11 thereby removably attaching the brace 10 to the photovoltaic panel 2 (Fig. 5). The swept boss 33 has a curvature 35 which provides angular variation relative to the photovoltaic panel 2 for a selection of clamping positions. A selected clamping position occurs at a second angle 17. The selected angle of inclination 3 of the photovoltaic panel 2 is the arithmetic sum of the first angle 16 and the second angle 17 minus 90 degrees, which latter represents the normal to the brace member 10 and the orientation of the clamp 31 (Fig's 1 and 13).

Fig's 7-10 show an alternate embodiment useful for large arrays of photovoltaic panels, where it is impractical to change position or alter the angle of inclination after installation. In the alternate embodiment, the rack 1 is comprised of a bendable member 11 inter-positioned with a stiff member 100, as discussed above for the preferred embodiment. The bendable member 11 has a distal end 12, a proximal end 13, longitudinal extent and opposing channels 15 (Fig. 11). The opposing channels 15 run along the longitudinal extent at lateral edges 19. The bendable member 11 is formed from a first strip 102 of sheet metal by folding the running edges of the strip inwardly to form the opposing channels 15, after which the opposing channels 15 bracket a gap 104. The bendable member 11 has at least a first bend 108 near the distal end 12 forming a first protrusion 14 and an at least a second bend 109 at the proximal end 13 forming a second protrusion 110. The at least first bend 108 forms a first angle 16 between the bendable member 11 and its protrusion 14 and the at least second bend 109 forms a third angle 18 between the bendable member 11 and its protrusion 110 (Fig's 7, 10 and 13). The bends are of sufficient radius to prevent fatigue of the material when the first and third angles are repeatedly manipulated. In forming the bends, the opposing channels 15 are hammered flat to remove buttressing structure at the instant locale of the bends.

In the alternate embodiment, the stiff member 100 is formed from a second strip 103 of sheet metal by deforming it longitudinally to take up a non-linear cross-section portion 105 (Fig. 11). The non-linear cross-section portion 105 is flanked at each running edge by the flanges 106. The flanges 106 are configured to slidingly interposition in the opposing channels 15 with the non-linear cross-section portion 105 protruding from the gap 104. The protrusion of shape adds buttressing structure to the brace 10 which prevents longitudinal flexion and thereby adds stiffness to the brace. Because the stiffness is added by shaping thin materials having compression strength, such as metal sheeting, a bracing function is achieved with minimal weight. Preferably, the non-linear cross-section portion 105 is arcuate, as shown in the figures. Other cross-sectional shapes could include rectilinear, V-shaped or another geometry (not shown).

In the alternate embodiment, the means for anchoring 20 the brace member 11 comprises ballast 21. Ballast 21 overlays the first protrusion 14 of the bendable member 11 to anchor it by applying its weight. The weight of the ballast 21 is sufficient to prevent movement of the brace, and therefore the photovoltaic panel 2, under environmental conditions, and particularly under conditions of high wind incidence. The first protrusion 14 is preferably bent up in a hook 107 at the distal end 12 to "cup" the ballast 21 between the hook 107 and the first angle 16.

In the alternate embodiment, the means for attaching 30 the brace member 10 to the photovoltaic panel 2 comprises at least one clamp 31 connected between the second protrusion 110 and an upper frame member of the photovoltaic panel 2 (Fig. 10). Preferably, there are at least two clamps 31 for each attachment location. The selected angle of inclination 3 of the photovoltaic panel 2, in the case of the alternate embodiment, is the arithmetic difference between the first angle 16 and the third angle 18 (Fig's 1 and 13).

The photovoltaic panel 2 may also be anchored at a lower end thereof by a foot member 40. The foot member 40 is a cut section of bendable member 11 having a first bend 108 and a second bend 109 at distal and proximal ends, respectively, to cradle a ballast 21 at the distal end and to form a support extension 36 at the proximal end (Fig. 6). The support extension 36 is attached to a lower frame member of the photovoltaic panel 2 by at least one clamp 31. Preferably, there are two foot members 40 for each panel and two clamps 31 for each foot. The first strip 102 of sheet metal and the second strip 103 of sheet metal are comprised of 25 gauge (0.43 mm) silver-anodized aluminum hardened to T5 or T6. The bends and folds of the strips are formed in a sheet metal bending brake. In climates with heavy corrosion (near salt water, for example), the aluminum sheet is preferably replaced with 316L stainless steel in 30 gauge (0.30 mm). The ballast 21 is preferably comprised of cast concrete block, but can alternatively be any heavy object, such as a sand bag, for example. The connecting member 32 is preferably comprised of extruded 6063 aluminum, but can alternatively injection molded with resin.

The rack 1 can easily be installed on location by clamping the connecting member 32 to the photovoltaic panel 2 and the foot 40 to the photovoltaic panel 2 with clamps 31. Ballast 21 is then placed on the first protrusions 14 of the bendable member 11 and the foot 40 to anchor them in place. Finally, the preassembled brace member 10 is clamped, with clamp 31, at a selected position along one of the lateral edges 19 of the bendable member 11, meanwhile flexing the pre-formed first bend 108, to thereby arrive at the selected angle of inclination 3. In the alternative case, the clamping at the proximal end 13 is to the second protrusion 110. The installation can take as little as 2 to 3 minutes and involve only a driver tool. The angle of inclination can be changed simply by loosening clamps and repositioning them relative to the brace, taking even less time. The bendable member 11 and the stiff member 100 can easily slide apart to facilitate cutting to custom size, if needed.

It is to be understood that the invention is not limited in its application to the details of construction and to the arrangements of the components set forth in the preceding description or illustrated in the drawings. For example, the ballast 21 may be placed against the lower frame member of the photovoltaic panel 2 thereby eliminating the foot 40 and related clamps 31 to further simplify. Also, it is to be understood that the phraseology and terminology employed herein are for the purpose of the description and should not be regarded as limiting.

Claims

CLAIMS What is claimed is:

1. A rack for mounting a photovoltaic panel to a substantially horizontal surface, comprising:

a brace member oriented at a selected incline angle;

a ballast having sufficient weight to removably anchor the brace to the substantially horizontal surface; and

a means for removably attaching the brace to the photovoltaic panel without defacing the panel;

whereby, the photovoltaic panel may be braced upright at a preferred angle of inclination and mounted to the substantially horizontal surface by the ballast and to the photovoltaic panel by the means for attaching, the mounting devoid of new holes drilled.

2. The rack of claim 1, wherein the means for removably attaching comprises at least one clamp connecting the brace member to the photovoltaic panel.

3. The rack of claim 1, wherein the means for removably attaching comprises a connecting member to connect with a frame element of the photovoltaic panel and at least one clamp to removably connect the brace to the connecting member.

4. A rack for adjustably mounting a photovoltaic panel to a substantially horizontal surface, comprising:

a bendable member having a distal end, a proximal end, longitudinal extent and opposing channels running along the longitudinal extent at lateral edges of the bendable member;

a stiff member inter-positioned with the opposing channels of the bendable member medially between the distal and proximal ends to leave a protrusion of the bendable member at the distal end while forming a brace between the protrusion and the proximal end;

a ballast having sufficient weight to removably anchor the brace by placement upon a portion of the distal end protrusion bent at a first angle; a connecting member to connect with a frame element of the photovoltaic panel by means of interlock thereto while protruding therefrom in a swept boss;

at least one clamp to removably connect the brace at a selected position at at least one of the lateral edges of the bendable member in the vicinity of the proximal end with the swept boss, the connection supporting the photovoltaic panel;

whereby, the photovoltaic panel may be braced upright at a selected angle of inclination and mounted to the substantially horizontal surface by means of the ballast and the clamp, the mounting otherwise without fasteners.

5. The rack of claim 4, wherein the bendable member is formed from a first strip of sheet metal by folding running edges of the strip inwardly to form the opposing channels and bracket a gap there between.

6. The rack of claim 5, wherein the stiff member is formed from a second strip of sheet metal by deforming it longitudinally so as to take up a non-linear cross-section portion flanked by flanges, the flanges configured to slidingly inter-lock in the channels with the non-linear lateral cross-section portion protruding from the gap, the protrusion adding sufficient structural stiffness to prevent longitudinal flexion of the brace.

7. The rack of claim 6, wherein the non-linear cross-section is arcuate.

8. The rack of claim 6, wherein the non-linear cross-section is rectilinear.

9. The rack of claim 6, wherein the non-linear cross-section is V-shaped.

10. The rack of claim 4, wherein the swept boss has a curvature providing angular variation relative to the photovoltaic panel, and wherein a selected variable angle at the selected clamping position is a second angle.

11. The rack of claim 10, wherein the selected angle of inclination is the sum of the first angle and the second angle minus 90 degrees.

12. A rack for mounting a photovoltaic panel to a substantially horizontal surface, comprising:

a bendable member having a distal end, a proximal end and longitudinal extent;

a stiff member inter-positioned with the bendable member medially between the distal and proximal ends to leave protrusions of the bendable member at the distal and proximal ends while forming a brace there between;

a ballast having sufficient weight to removably anchor the brace by placement upon a portion of the distal end protrusion bent at a first angle;

at least one clamp to connect the brace to the photovoltaic panel, the clamp connecting at a portion of the proximal end protrusion bent at a third angle;

whereby, the photovoltaic panel may be braced upright at a preferred angle of inclination and mounted to the substantially horizontal surface by means of the ballast and the at least one clamp, the mounting otherwise without fasteners.

13. The rack of claim 12, wherein the bendable member is formed from a first strip of sheet metal by folding running edges of the strip inwardly to form the opposing channels and bracket a gap there between.

14. The rack of claim 13, wherein the stiff member is formed from a second strip of sheet metal by deforming it longitudinally so as to take up a non-linear cross-section portion flanked by flanges, the flanges configured to slidingly inter-lock in the channels with the non-linear lateral cross-section portion protruding from the gap, the protrusion adding sufficient structural stiffness to prevent longitudinal flexion of the brace.

15. The rack of claim 14, wherein the non-linear cross-section is arcuate.

16. The rack of claim 14, wherein the non-linear cross-section is rectilinear.

17. The rack of claim 14, wherein the non-linear cross-section is V-shaped.

18. The rack of claim 12, wherein the selected angle of inclination is the difference between the first angle and the third angle.