Spring clip

A panel array support assembly has lower support joists supporting varied panel rails, to which are connected panel holding device or clips. The panel clips are spring-based and configured so that the length of each clip extends in a direction along the length of the panel rails. The panels are supported well inside of the edges extending in the same direction as the panel rails.

FIELD OF THE INVENTION

This invention relates to support systems for panels and panel-like structures, such as solar energy collection systems, and more particularly to a support system for an array of photovoltaic panels, in addition to a method of quickly assembling the same for activation.

BACKGROUND OF THE INVENTION

Many conventional photovoltaic (solar) panel arrays include a plurality of solar panels, optimally arranged for converting light incident upon the panels to electricity. Various support systems are used for attachment to roofs, free-field ground racks, tracking units, or other substrates/structures. Typically, these support systems are costly, heavy, structurally inferior, mechanically complicated and the installation is labor-intensive. Once the support structure is in place, mounting the solar panels on the support structure can be very difficult. It is further complicated by the tendency of some large solar panels to sag and flex, thereby rendering the panel mounting unstable. Panel repair and adjustment thereby become more difficult.

A conventional two-dimensional panel support system generally includes off-the-shelf metal framing channels having a C-shaped cross-section, such as those sold under the trademarks UNISTRUT™ or BLIME™. These are improvised for use as vertical and horizontal (or upper and lower) support members. The photovoltaic (solar) panels12, or other panel-like structures, are directly secured to upper support members (30inFIG. 3) and held in place by panel clips or panel holders45(as depicted inFIG. 3). These panel clips are manufactured in a wide range of sizes and shapes. The clips45are conventionally positioned and attached about the panel edges once each panel is arranged in place.

In a conventional, free-field ground rack system for mounting solar panels, (as depicted inFIG. 1) vertical support elements, such as I-beams14, are spaced and securely embedded vertically into the ground. Tilt-mounting brackets16are secured to the top of each I-beam, such that a tilt bracket flange extends above the I-beam at an angle, as best seen inFIG. 2A. In this arrangement, two UNISTRUT™ lower joists20or a combined support structure13span the tilt-mounting brackets16and are secured thereto, using bolts240through apertures216(FIG. 3). As seen inFIG. 2B, UNISTRUT™ rails30are positioned across and fastened to lower joists20. To secure each rail30to the corresponding lower joists20, a bolt through a bolt-hole made in the rail sidewall attaches to a threaded opening in a nut plate (not shown) inserted inside the channel of the UNISTRUT™ joist. The nut-like plate engages and tightly secures against the upper flange of the joist's C-channels as depicted inFIG. 2A.

Once the bi-directional matrix span10is assembled, each solar panel12is secured in place by panel holding clips45connected using apertures145in panel rails30(FIG. 4). A select quantity of said clips is secured to the upper support rails about the perimeter of each panel. Each panel clip45is put in place and securely tightened to support rails30. This installation process, especially if involving multiple clips45, is often costly, inaccurate, dangerous and time-consuming.

Another example of a support system for panel-like structures is shown in U.S. Pat. No. 5,762,720, issued to Hanoka et al., which describes various mounting brackets used with a UNISTRUT™ channel. Notably, the Hanoka et al. patent uses a solar cell module having an integral mounting structure, i.e. a mounting bracket bonded directly to a surface of the back-skin layer of a laminated solar cell module, which is then secured to the channel bracket by bolts or slideable, engaging C-shaped members. Other examples of panel support systems are shown in U.S. Pat. No. 6,617,507, issued to Mapes et al.; U.S. Pat. No. 6,370,828, issued to Genschorek; U.S. Pat. No. 4,966,631, issued to Matlin et al.; and U.S. Pat. No. 7,012,188, issued to Erling. All of these patents are incorporated herein as reference.

Foldable support arrays10of upper support rails30and lower support joists20are found in the newer art developed by some of the inventors of the present application. One such example is depicted inFIG. 4. A detailed view of the intersection between upper support rail30and lower support joist20is depicted inFIG. 5. Some of the present inventors have developed a number of foldable support systems for solar panels and other panel-like structures. These are listed in the attached information disclosure documents.

The folding support arrays10of these support systems solve many problems well known in the art of panel array supports. However, even with a reliable, easily-deployed support array, there are still difficulties in the installation of the panels themselves, especially solar panel arrays. In particular, existing support systems require meticulous on-site assembly of multiple parts, performed by expensive, dedicated field labor. Assembly is often performed in unfavorable working conditions, i.e. in harsh weather or in difficult terrain, without the benefits of quality control safeguards and precision tooling. Misalignment of the overall support assembly often occurs, especially when mounting panels to the upper panel rails30with clips45. This can jeopardize the supported solar panels.

Another problem is the spacing of the photovoltaic (solar) panels12. It is important to accommodate panel expansion and contraction as a result of changes in the weather. Panels must, therefore, be properly spaced for maximum use of the bi-directional area of the span. Various geographical areas may require different panel spacing due to the distinct temperature patterns of each given location. It is also challenging to precisely space the panels on-site using existing support structures and panel clips45, without advanced (and expensive) technical assistance.

For example, with one of the existing conventional designs described above (as depicted inFIGS. 2A and 2B), until the upper rails30are tightly secured to the lower support structure13of multiple support joists20, each upper rail30is free to slide along the lower support joists20and, therefore, needs to be properly spaced and secured once mounted on-site. Additionally, since the distance between the two lower joists20is fixed on account of the drilled bolt-holes through the bracket, it is conventionally preferred to drill the holes on-site, so that the lower joists can be precisely aligned and attached through the pre-drilled attachment holes of the tilt bracket. Unfortunately, the operation of drilling the holes on-site requires skilled workers, and even with skilled installation, misalignment of the support structure and/or the solar panels supported by the structure may still occur (i.e. improperly spaced or slightly skewed from parallel).

The difficulties are compounded by the necessity of drilling holes145to accommodate connectors for the panel clips or holders45. If this process is executed on-site, accurate placement of the solar panels becomes extremely difficult. Even if the apertures145are precisely drilled at the factory, an additional degree of imprecision is introduced when the panel clips45have to be connected to the upper support rails30while being positioned to hold panels12. This is an awkward arrangement, even in the hands of expert installers. Normally, it is accomplished by connecting one (lower) portion of the panel clip45to the upper support rail30, and then positioning panel12to be secured by another (top) portion of panel clip45. Of necessity, this adds an additional assembly step for each panel clip45, while still offering opportunities to accidently introduce misalignment in the overall panel array10.

FIG. 5includes a cross-sectional view and shows an improved prior art arrangement for mounting a panel array. Panels12are held using gaskets130in panel clip45. The panel clip is held to panel rail30using aperture145, though which a connector (not shown) holds the panel clip45to the panel rail30. The panel rail30is held to support joist20by means of threaded connector43, which extends from the bottom of the panel rail30through separating washer24, through support joist20and into tilt-mount bracket16. The through connector43is held by nut44. Despite the effectiveness of this particular arrangement, there are still difficulties to be addressed, as elaborated on below.

Misalignment difficulties are exacerbated by the flexing of the panels12and sagging permitted by the natural flexibility of the panels. The sagging of the panels12can cause the panels to work out of their clips or holders45. Improper installation, which occurs frequently in conventional systems, can lead to dislocation of the panels due to sagging or atmospheric conditions. The use of a wide variety of different mounting positions and panel array arrangements also worsens the stability problems caused by panel sagging or deflection. Further, certain mounting positions will make the panels12more vulnerable to atmospheric disruptions, such as those created by wind and precipitation. All of these variables also complicate electrical connections to the panels.

One method of correcting misalignment is through the use of larger and more effective panel clips45. However, there are drawbacks in this approach. In particular, there are only a limited number of points at which panel clips can be connected. Accordingly, even with enlarged panel clips45, only extremely limited portions of the lengths of panels can be secured.

The problems caused by misalignment due to sagging are further exacerbated in some environments by the accumulation of ice on the panels. This adds weight. Icing can also be a problem, particularly when water works its way into crevasses found throughout the overall panel array10, and then freezes and expands. Still further, icing can become particularly problematic with respect to panel clips45extending beyond the panels12or the support rails30. Accordingly, the use of larger panel clips45and increased numbers of them have typically added to the problems of ice formation on the overall panel array10.

Therefore, a need exists for a low-cost, uncomplicated, structurally strong panel support system, and assembly method, so as to optimally position and easily attach the plurality of photovoltaic panels, while meeting architectural and engineering requirements. Further, there is an urgent need for a panel support system that will maintain the security of the mechanical connections of the solar panels to support rails despite the flexing of the panels (and support structure) caused by any of gravity, vibration, or environmental factors. Likewise, there is an urgent need to simplify the assembly of panel support systems, especially the connections between the upper support rails and panel clips. Such simplification should not compromise the stability or strength of the connections between the panels and the support system.

Conventionally, solar panels are supported at two opposite edges of the panel along the entirety of the panel length. This type of edge support, while convenient, permits panel buckling and loosening, as previously described. This in turn necessitates adjustments in the panel holding structures, which are often not successful since they are conventionally limited to two edges of the panel. An arrangement in which panels could be supported at positions other than two edges could eliminate many problems resulting from panel buckling, sagging, and loosening.

At present, none of the conventional panel support systems offer the capabilities of eliminating the problems mentioned above. An improved support system would achieve a precise configuration in the field without extensive work at the installation site. The use of such an improved system would facilitate easy, secure placement of solar panels onto the support structure prior to the final tightening of the panel clips. The shipping configuration of the improved support system would be such so as to be easily handled in transit while still facilitating rapid deployment.

Rapid deployment must be facilitated on any type of substrate providing stable support for the panels, without damaging or otherwise compromising the panels or substrate. Rapid deployment would also include rapid and secure mechanical connection of the panels using simple panel clips in a manner that would keep the panels secure despite loosening tendencies from panel sagging and flexing, or any number of other factors. Final panel clip tightening would not be necessary until all panels were in place. The preferred system would also minimize ice accumulation on the panel array, especially at the panel clips.

SUMMARY OF THE INVENTION

It is a primary object of the present invention to improve upon conventional photovoltaic solar panel systems, especially with regard to assembly and installation.

It is another object of the present invention to provide a support and installation system for solar panels in which the panels are less likely to be damaged during installation.

It is a further object of the present invention to provide a simplified support system for solar panels that is easily installed while still facilitating a precise configuration.

It is an additional object of the present invention to provide a solar panel support system that can be assembled very quickly on site, due to fewer assembly steps.

It is still another object of the present invention to provide a solar panel support system that can achieve close tolerances during field installation, without the necessity of skilled on-site labor.

It is still an additional object of the present invention to provide a solar panel support system which can be easily adapted to a wide variety of solar panel array sizes and shapes.

It is yet another object of the present invention to provide a solar panel support system which minimizes the necessity for precise measurements at the installation site.

It is again a further object of the present invention to provide a solar panel support system that can be arranged in a variety of different positions and at varying exposure angles.

It is still an additional object of the present invention to provide a solar panel support system that can be precisely configured to a specific environment.

It is another object of the present invention to provide a support system for solar panels and other panel-like structures in which degradation caused by metal-to-metal contact is substantially reduced.

It is again another object of the present invention to provide a support system for panel-like structures in which accommodation is made for movement caused by changes in temperatures, humidity or other environmental considerations.

It is still a further object of the present invention to provide a simplified connection system for solar panels using a reduced number of parts.

It is still an additional object of the present invention to provide a solar panel mounting system that can accommodate easy installation and removal of panels on adjacent frameworks.

It is still another object of the present invention to provide a panel support system wherein a wide variety of different sizes and shapes of panel configurations can be accommodated, and easily installed, as well as removed.

It is again a further object of the present invention to provide a panel support system in which panels can be easily attached to support brackets without incurring damage to the panels.

It is still another object of the present invention to provide a support system for panels or panel-like structures for a wide range of uses, positions, and configurations.

It is still a further object of the present invention to provide a panel mounting system, which is entirely self-contained with its own installation interface.

It is again an additional object of the present invention to provide a panel mounting system that facilitates quick, secure mounting of the panels once the support system is deployed.

It is yet another object of the present invention to provide a panel support system that can accommodate flexing, sagging, and other deformation of the panels while maintaining a secure connection thereto.

It is yet a further object of the present invention to provide a panel mounting system which facilitates increased panel clip capacity.

It is again an additional object of the present invention to provide a panel mounting system that facilitates safe tightening of panel clips.

It is yet another object of the present invention to provide a panel clip or connector that can accommodate for flexing of both the panel and the support system.

It is still a further object of the present invention to provide a panel connection system that can facilitate rapid installation while maintaining a secure hold on the panels or panel-like structures.

It is yet an additional object of the present invention to provide panel rails configured to ensure a secure panel connection, without final tightening of all the panel clips.

It is yet a further object of the present invention to reduce the cost of panel support structures by eliminating the overall length of structural aluminum panel rails, such as those currently used in conventional systems, without sacrificing the strength of the overall structure.

It is still an additional object of the present invention to provide a panel support system admitting to substantial flexibility of configuration.

It is again another object of the present invention to provide a panel support system which limits ice formation at various parts of the panel array, especially the panel clips.

It is again a further object of the present invention to provide a panel support system having a profile which limits or avoids overhanging structures extending from the supported panels.

It is again another objection of the present invention to provide a panel support system that accommodates folding for transport.

It is again an additional object of the present invention to provide a panel support system, including panel clips, that is not susceptible to loosening or allowing panels to shift.

It is still another object of the present invention to provide a panel support system in which conditions for standing water accumulation are drastically reduced, as is ice accumulation.

It is yet a further object of the present invention to provide a panel support system that facilitates superior support of panels to avoid sagging.

It is again another object of the present invention to provide a panel support system in which panels are held by quick-connect/quick-release spring mechanisms.

It is the overall goal of the present invention to provide a comprehensive panel mounting system that facilitates rapid and secure installation, including deployment of the panel support structure, and placement of the panels on that support structure.

These and other goals and objects of the present invention are achieved by a panel holding clip configured to hold at least one panel to an upper panel rail in a panel support array. The panel holding clip includes a base structure having a horizontal support extending along the upper panel rail. The panel holding clip also includes a first upright structure extending perpendicularly from the base structure and having a distal end. A first perpendicular holding structure extends horizontally from the distal end of the upright structure. A spring structure is positioned to exert force on an external panel held by the panel holding clip.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As has been previously discussed, conventional panel (solar and other types) support systems tend to be constituted by two dimensional arrays having lower support joists20and upper support rails30. Panel clips or holders45are then field-mounted on the upper support rails so that the panels12can be placed thereon, and secured with additional portions of the clips. Even with factory pre-alignment and set up of support joists20and upper panel rails30, conventionally, there is little that can be done about the many assembly steps required to place both the panel clips45and the panels12on the upper support rails30.

The present inventions, as depicted inFIGS. 6-18, constitute a departure from the prior arrangements. In particular, panel clips6still hold panels12along their edges. However, panel rails30are not found along the longitudinal (parallel to the length of the panel rails) edges of the panels12. Rather, the panel rails30support panels12at positions well inside of the edges of the panels12. This results in far superior support for the panels12than can be found in any of the other conventional arrangements used for supporting solar panel arrays. This is clearly seen inFIGS. 15-18. This novel support arrangement prevents a substantial amount of the sagging, twisting, warping, and loosening of the panel clips found in conventional solar panel support systems.

Panels12are supported and held by clips6only at the ends of the panels12, as depicted inFIGS. 6-18. Because the panel rails30are covered along most of their lengths by panels12, the panel clip6can be installed only at the ends of the panel rails30, or at gaps between panels12, as depicted inFIGS. 17 and 18.

The holding capability of panel clips6is enhanced by spring-biased structures7that apply additional force against panels12to hold them in place. Despite the fact that additional spring force is provided by the spring-biased mechanisms (such as spring structure7), the panels12are easier to install due to the flexibility provided by the spring mechanisms. Because of the spring action, panels12can be easily slid into panel clips6that are already secured to the panel rails. This spring action provides enough flexibility that panels12can be adjusted beneath secured panel clips6, without damage to the panel12, or extensive loosening and tightening operations.

The new mounting configurations depicted inFIGS. 6-18also provide superior de-icing characteristics. This is achieved by allowing considerably fewer surfaces or structures on which water can accumulate. For example, since sagging is eliminated from panels12, water cannot accumulate on them, thereby eliminating the formation of ice deposits and/or the build-up of excessive and unnecessary weight.

Also, the narrow profiles of each of the clips6provide very little structure that is conducive to the accumulation of water and the formation of ice at the intersections of the panel clips6and other structures. With reference toFIGS. 6 and 7, each perpendicular holding structure62,62(A) and62(B) has a corresponding beveled surface66,66(A) and (B), respectively, to help prevent the accumulation of water at the intersection between the clip6and the panel12. The arrangement whereby the edges of most of the panel are free from an intersection with a panel rail30reduces opportunities for water accumulation and ice formation.

Further, the width of the panel clip6is such that the panel clip6is a bit wider than the width of the panel rail30. This prevents water collection, as well as the opportunity for ice formation, at the intersection or interface between panel clip6and panel rail30.

For the most part, when water flows toward the edges of panel12, it is not held by intersections of surfaces from the side of panel12and the upper edge of panel rail30. Accordingly, the water simply slides off the open edges of panel12. Even one embodiment of spring structure7is arranged so that water will flow off the surface of panel rail30(by means of legs71(A),71(B)).

The first embodiment of the novel panel clips6is depicted inFIG. 6. This is a front perspective view of a single-sided panel clip6facing in the direction of the panel12edge, which is to be held. The surface against which the panel edge will interface is provided by upright structure61. This, in turn, supports a perpendicular holding structure62, which is configured to extend over the surface of panel12(not shown). Panel clip6is supported by legs64(A) and (B) and horizontal support or cross piece63. The cross piece provides structural support for a connector aperture65, through which a connector9(inFIG. 12) can be inserted to hold panel clip6to the top of panel rail30.

Spring structure7is made of a flexible, deformable material, and includes a ridge structure72. Pressure on ridge72, for example from a panel12(not shown inFIG. 7), will serve to deform ridge72so that the panel can fit under perpendicular holding structure62. Because the material constituting spring structure7is resilient, ridge72will continue to exert force against panel12(not shown), serving to hold it tightly in place. Legs71(A),71(B) are operative to prohibit lateral movement to both the spring structure7and the panel clip6.

For the sake of design and arrangement flexibility, a double panel clip6constitutes another embodiment of the present invention, as depicted inFIG. 7. The double panel clip6is the same as a single panel clip6, except that a second upright structure61(B) is included. The side profile of the double panel clip6arrangement is depicted inFIG. 9, which can be easily compared to the single-side profile ofFIG. 8.

The only difference in the two-sided spring structure7arrangement is found in the comparison of the structures depicted inFIG. 10(A-B)andFIG. 11(A-B). In particular, first and second ridge72(A) and (B) are found with the double-ended arrangement. This permits a second panel12(not shown) to be inserted beneath the second perpendicular holding structure62(B). In both configurations of the spring structure7, a connector aperture73is placed to align with the connector aperture65in the horizontal support structure63of panel clip6.

The double panel clip6structure ofFIGS. 7,9,11(A),11(B) and13also includes a spring structure7having an additional set of legs,71(C),71(D). Just as there is a second upright structure61(B), there is also a second perpendicular holding structure62(B) with its own beveled edge66(B).

Because the spring structure7has a double-ridge arrangement,72(A),72(B), two external panels12can be held by virtue of the spring action exerted by ridges72(A),72(B), before the final tightening of connector9is carried out. This greatly aids in the rapid installation of panels, a major object of the present inventive system.

FIGS. 12 and 13depict through-connector9(preferably a threaded screw) holding both single and double panel clips6,6(A) and (B), respectively, onto the surface of a panel rail30. The security of connector9is facilitated by lock washer91. However, other connection techniques can be used besides the configuration of connector9and lock washer91depicted inFIGS. 12 and 13.

Spring action to hold panels12can be applied by other mechanisms besides the precise spring structure7depicted inFIGS. 6-13. For example, inFIGS. 14 and 15, spring pressure is applied to panel12through the perpendicular holding structure62of clip6. The spring action comes from a resilient bushing8, which functions as a spring. This spring action allows the Z-shaped clip6to exert varying levels of pressure on a panel12through the perpendicular holding structure62. The level of spring action is adjusted by connector9operating through collar81on resilient member8.

Panel clip6, shown inFIGS. 14-15, is similar to those inFIGS. 6-13with certain exceptions. For example, the panel clips ofFIGS. 14 and 15are Z-shaped, with a flat horizontal flange68, having a connector aperture65. Horizontal flange68lies flat on panel rail30. Like previous embodiments, the width of the clip6is somewhat greater than the width of rail30so that the opportunities for water accumulation, and thus ice formation, are limited.

Resilient member8is preferably a spring or a resilient bushing (the bushing being made of polyurethane or a similar resilient material that exhibits a spring-like quality) so that there is flexibility in the overall holding arrangement of panel clip6, as depicted inFIG. 14. The spring tension exerted by resilient member8is controlled by collar81, which presses down uniformly on the top of resilient member8. The overall tension is controlled by connector9, which passes through collar81, resilient member (i.e., bushing or spring)8, connector aperture65, and into panel rail30.

FIGS. 15-18depict various embodiments of the present invention holding panels12to panel rails30. Other than the use of the inventive panel clip6configurations, the arrangement ofFIGS. 15-18differs substantially from support arrangements for conventional solar panels.

Considering all ofFIGS. 15-18, it is important to note that panels12are not supported along their outer edges, as is the case with conventional panel support arrangements. Rather, the lengths of panel rails30run along the interior of panels12, as depicted most clearly inFIGS. 16 and 18. As depicted in these drawings, the edges of the panels are not supported along their lengths by panel rails30. The result is that water is free to flow down between the panels12, and does not accumulate and/or form ice in freezing conditions. This is crucial in reducing the weight of the panel array over time.

Further, because panels12are supported away from their edges, sagging in the middle of the panels is virtually eliminated. This is crucial since sagging often results in water accumulation and ice formation. The elimination of sagging also eliminates twisting, warping, and the like. These are factors that tend to tear panels loose from the panel clips. The result of the arrangements ofFIGS. 15-18, when used in conjunction with the panel clips ofFIGS. 6-14, is a far more stable panel array. Because such a panel array resists the accumulation of water (normally resulting in extra weight), the array is far more stable over the course of time.

Since panels12are not held along their entire edges, handling of the panels becomes much easier. Supporting the panels as described (i.e., closer to the middle of the panels and at two places) results in not only a more stable configuration, but also one that is easier to maintain, as the handling of panels for maintenance and replacement can be carried out much more easily and efficiently.

While a number of preferred embodiments have been described by way of example, the present invention is not limited thereto. Rather, the present invention should be understood to include any and all variations, modifications, adaptations, permutations, derivations, and embodiments that would occur to one skilled in this art in possession of the teachings of the present invention. Accordingly, the present invention should be construed to be limited only by the following claims.