Panel mounting bracket with grounding mid-clamp and related methods

A system for mounting a plurality of solar panels on a building may include mounting brackets each including a base to be positioned on the building and a vertical extension coupled to the base. A plurality of interior mounting clamps may each include a leg to be coupled to the vertical extension of a given panel mounting bracket. Each interior mounting clamp may also include a first lateral arm coupled to a distal end of the leg on a first side thereof for securing a first panel to the given panel mounting bracket with the first lateral arm having a first thickness, and a second lateral arm coupled to the distal end of the leg on a second side thereof opposite the first side for securing a second panel to the given panel mounting bracket with the second lateral arm having a second thickness less than the first thickness.

TECHNICAL FIELD

The present disclosure generally relates to mounting fixtures, and, more particularly, to mounting fixtures for rooftop panel installations, such as for solar panels, for example.

BACKGROUND

Solar panels, such as photovoltaic (PV) and solar water heating panels, are frequently used to take advantage of electrical power generation and heating properties of sunlight. To provide space savings and potentially enhanced efficiency, solar panels are in many cases installed on rooftops of buildings (e.g., office buildings, houses, pavilions, free-standing structures with or without walls, etc.). However, because of winds and storms, the mounting fixtures used for installing solar panels on buildings need to be sufficiently strong and durable to reduce the chances of damage or injury from a panel coming loose during a storm, etc.

Various mounting fixtures have been developed for solar panel installation. For example, one particularly advantageous system for mounting a solar panel(s) on a building is disclosed in U.S. Pat. No. 9,628,018 to Stapleton, which is hereby incorporated herein in its entirety by reference. The system may include a plurality of panel mounting brackets each including a base to be positioned on the building, and a vertical extension having a proximal end coupled to the base and a distal end vertically spaced apart from the base, with the distal end defining a fastener channel therein. The system may also include a plurality of mounting clamps each including a bottom flange, and a top flange spaced apart from the bottom flange and partially overhanging the bottom flange and defining a slot therebetween to receive a lip of the solar panel. An end extension may couple respective ends of the bottom flange and top flange together, and a fastener channel connector may be coupled to the bottom flange and configured to be slidably received within the fastener channel. Other solar panel mounting fixtures and systems are disclosed in U.S. Pat. Nos. 9,484,853; 9,397,605; 9,145,685; and 9,057,545, also to Stapleton, all of which are hereby incorporated herein in their entireties by reference.

Despite the existence of such mounting fixtures, further enhancements may be desirable in some applications to help simplify and expedite the installation of solar panels on buildings or rooftops.

SUMMARY

A system for mounting a plurality of solar panels on a building may include a plurality of panel mounting brackets each including a base to be positioned on the building and a vertical extension having a proximal end coupled to the base and a distal end vertically spaced apart from the base. The system may also include a plurality of interior mounting clamps each including a leg having a proximal end to be coupled to the distal end of the vertical extension of a given panel mounting bracket and a distal end. Each interior mounting clamp may also include a first lateral arm coupled to the distal end of the leg on a first side thereof for securing a first solar panel to the given panel mounting bracket with the first lateral arm having a first thickness, and a second lateral arm coupled to the distal end of the leg on a second side thereof opposite the first side for securing a second solar panel to the given panel mounting bracket, with the second lateral arm having a second thickness less than the first thickness.

By way of example, the second thickness may be in a range of 60% to 80% of the first thickness. Furthermore, the system may also include at least one first set screw carried by the first lateral arm to be screwed into contact with the first solar panel, and at least one second set screw carried by the second lateral arm to be screwed into contact with the second solar panel. In addition, bottom surfaces of the first and second lateral arms may be serrated.

In accordance with one example embodiment, one or more grounding wires may be coupled between at least some of the panel mounting brackets. Furthermore, the distal end of the vertical extension may have a fastener channel therein, and a respective fastener may be used to couple the proximal end of each interior mounting clamp to the distal end of the vertical extension.

In one example implementation, the system may also include a plurality of end mounting clamps to couple an outer edge of solar panels on a periphery of the plurality of solar panels to the distal ends of the vertical extensions of respective panel mounting brackets. By way of example, each end mounting clamp may include a bottom flange, a top flange spaced apart from the bottom flange and partially overhanging the bottom flange and defining a slot therebetween to receive the outer edge of the respective solar panel with the top flange to be connected to the distal end of the vertical extension of the respective panel mounting bracket, and an end extension coupling respective ends of the bottom flange and top flange together.

In accordance with an example embodiment, each panel mounting bracket and each interior mounting bracket may comprise aluminum. Furthermore, the base may have a plurality of mounting holes on opposing sides of the vertical extension.

A related mounting clamp for use with a panel mounting bracket, such as those described briefly above, is also provided. Moreover, a related method for mounting a plurality of solar panels on a building may include positioning a plurality of panel mounting brackets on the building, such as those described briefly above. The method may also include positioning a first solar panel on a given panel mounting bracket, and coupling an interior mounting clamp to the given panel mounting bracket, with the interior mounting clamp including a leg having a proximal end to be coupled to the distal end of the vertical extension of the given panel mounting bracket and a distal end, a first lateral arm coupled to the distal end of the leg on a first side thereof for securing the first solar panel to the given panel mounting bracket with the first lateral arm having a first thickness, and a second lateral arm coupled to the distal end of the leg on a second side thereof opposite the first side, with the second lateral arm having a second thickness less than the first thickness. The method may further include positioning a second solar panel on the given panel mounting bracket beneath the second lateral arm.

DETAILED DESCRIPTION

Referring initially toFIGS. 1-8, an assembly30for mounting one or more solar panels31on a building (e.g., on a roof) is first described. The assembly30illustratively includes a mounting bracket32(which is also referred to as a “foot” herein) for installing solar panels or modules31. By way of background, solar modules or panels are typically mounted to racking using clamps that grip the module and hold it tight to rails which are mounted to rooftops by “L” shaped feet. The foot32illustrated inFIG. 1advantageously avoids the need for such rails and clamps by mounting panels to roofs through the use of multiple feet (e.g., four feet, although other numbers of feet may be used), which are attached to the underside of each panel. More particularly, each panel31may include an outer frame33defining a lip34on the underside thereof, and in the example embodiment illustrated inFIGS. 7 and 8the outer frame carries a photovoltaic cell array35therein (although the assembly30may also be used for mounting solar hot water heating panels as well, for example).

In the illustrated example, the foot32has a generally rectangular-shaped central vertical extension portion36with one or more hollow central area(s) or channel(s)37therethrough. A proximal end38of the vertical extension36is coupled to a flange or base39of the foot32, and a distal end40of the vertical extension is vertically spaced apart from the proximal end, as seen inFIG. 1. An upper fastener channel slot or groove41is defined in the distal end40(seeFIG. 2), though grooves may instead or in addition be provided on either or both sides of the vertical extension36in some embodiments, if desired. The foot32has a height h and a width w, which in an example embodiment may both be three inches, but other dimensions may also be used in different embodiments.

The base39illustratively includes two side extensions42,43that extend outwardly away from the vertical extension36so that the vertical extension is centered on the base (although it need not be centered in all embodiments). Thus, when the bottom surface of the base39sits flat on a rooftop or roof deck44upon installation, the vertical extension36points upward or normal to the surface of the roof (although the vertical extension may form different angles with respect to the base besides 90° in different embodiments). Serrations or other surface features may optionally be included on portions of the upper surface of the distal end40and/or the bottom surface of the base39, if desired. The serrations may advantageously provide for improved electrical grounding with the frame of the panel, as well as increased grip or friction, for example, as will be appreciated by those skilled in the art.

In the illustrated example, the feet32are attached to the underside lip34of each panel frame33, as shown inFIGS. 4 and 7. While still on the ground, the installation technician may advantageously attach the feet32to the bottom of each panel on their longer sides (e.g., top and bottom sides) with the front edge of the foot facing out from the panel using an under-mounting clamp50. However, the feet32may be attached to the other sides of the panels31as well in some embodiments, and the panels may also be attached to the feet after the feet have been installed on the rooftop44, if desired.

The mounting clamp50illustratively includes a bottom flange51, a top flange52spaced apart from the bottom flange and partially overhanging the bottom flange (seeFIG. 3) to define a slot therebetween, and an end extension53coupling respective ends of the bottom flange and top flange together. The slot is configured to engage or receive the lip34of the solar panel31on the outside edges of the solar panels at the end of each row of panels, as seen inFIG. 7. The mounting clamp50further illustratively includes a fastener channel connector54coupled to the bottom flange51and configured to be slidably received within the fastener channel41.

In the present example, the fastener channel connector54illustratively includes a T-shaped connector or slide bar coupled to the bottom flange51on a side thereof opposite the top flange52(i.e., on its bottom side). The T-shaped connector57is configured to be slidably received within the fastener channel41, as seen inFIGS. 1 and 2. The fastener channel connector54may first be attached to the solar panel31, and then the feet32connected to respective mounting clamps50. Another approach is that the mounting clamps50may be coupled to respective feet32, and the entire assembly30(i.e., mounting clamp plus foot) may then be connected to the solar panel31. The mounting clamp50further illustratively includes a retaining set screw(s)55which may be tightened to secure the lip34within the slot between the bottom and top flanges51,52, and a slide bar retaining bolt58and a corresponding nut59. The set screws55may also advantageously facilitate an electrical grounding connection with the foot32, as will be discussed further below.

A first column of panels31may then be attached on the roof44with deck screws60through mounting holes61in the side extensions42,43on the outward or perimeter side of the array, typically in a straight line. In some instances, a sealant may be used under each foot32, if desired. Various types of sealant may be used, such as caulking, tar, Butyl tape, etc. An adjacent column of solar panels31may then be attached with additional feet32adjacent to the first column of solar panels so as to share the second set of feet (seeFIGS. 5 and 6) between them. That is, the fastener channel41of each vertical extension portion may be of sufficient dimensions or length to slidably receive two (or more) fastener channel connectors54therein. While the feet32are shared between adjacent panels, the mounting clamps50retain each solar panel31independently. This allows each solar panel31to be installed and secured individually, and in the event that a solar panel is to be removed from an array, this can be done independently without loosening the adjacent solar panel, which is generally not possible with typical panel or panel mounting arrangements.

The installation process may be repeated for each column of solar panels31to be installed, until the last column of solar panels is reached. On the outer perimeter of the last solar panel31, one mounting clamp50may be used per foot32to attach to the outer edge of each of the perimeter solar panels (see, e.g.,FIGS. 4 and 7).

A significant advantage of the assembly30is that it may advantageously be connected or coupled to a respective solar panel31on the ground, rather than having to be coupled to the solar panel on the roof44where this is more difficult (and potentially more dangerous), and where it is much harder to recover dropped tools, screws, nuts, washers, or other parts. Moreover, this may also help expedite the installation process.

The hollow channels or passageways37in the vertical extension36may serve as wire management channels, which may be used for keeping electrical transmission wires (e.g., for PV panels) or temperature sensor wires (e.g., for a water heater panels) secured in place. However, the cross-support members56which define the channels37need not be included in all embodiments, although even when the channels are not used for routing wires the cross-support members may provide added rigidity and/or stability to the feet32. It should also be noted that the vertical extension36of the foot32need not be hollow in all embodiments, and that different shapes beside a rectangular shape may also be used for the base39and/or the vertical extension in some embodiments. One example material for the foot32and the mounting clamp50is aluminum, which may be extruded into the desired shape, although other suitable materials may also be used in different embodiments. The various screws and fasteners described herein may be stainless steel, brass, galvanized steel, etc.

Here again, a sealant may optionally be used under each foot32so that the screws60are screwed through the foot32and sealant into the roof or decking44at desired locations. By way of example, two or more feet32may be secured to the roof44to receive one side of the panel, i.e., two (or more) feet are used on each of the top and bottom sides or edges of the solar panel31, as shown inFIG. 7, although in some embodiments a single foot may be used.

It should be noted that the above-described mounting assembly30may be used with a variety of roof types, including flat and sloped roofs, and over different types of roof coverings (e.g., shingles, tiles, panels, etc.). Moreover, the mounting feet may be used for installations other than on rooftops, such as where mounting to the side of a building or other structure is required.

Turning toFIGS. 9-15, another example clamp60which may be used with the mounting bracket32is now described. Generally speaking, the clamp60is an interior mounting clamp in that it may be used between two adjacent solar panels31to couple them both to the same mounting bracket32(similar to the configuration shown inFIG. 6), as opposed to an end clamp which is only connected to the outer edge of panels on the periphery of a panel array (seeFIG. 4). The interior mounting clamp60may in this respect also be referred to as a “mid clamp” herein, as it is suited for connection in the middle between two adjacent solar panels31on a given bracket32.

In the illustrated example, the mid clamp60has the basic profile of an upright “T”, with a leg61having a proximal end62to be coupled to the distal end38of the vertical extension36of a given panel mounting bracket32, and a distal end63. Each mid clamp60also illustratively includes a first lateral arm64coupled to the distal end63of the leg61on a first side thereof for securing a first solar panel31to a panel mounting bracket32, and a second lateral arm65coupled to the distal end of the leg on a second side thereof opposite the first side for securing a second solar panel to the same panel mounting bracket. It should be noted the in the illustrated example, the arms64,65are straight and extend perpendicularly out from the leg61, but that the arms may take other shapes (e.g., curves or arcs) and extend outward at other angles as well.

Furthermore, the first lateral arm64has a first thickness T1, while the second lateral arm65has a second thickness T2less than the first thickness. Considered alternatively, the second lateral arm65is thinner than the first lateral arm65. This advantageously allows a first solar panel31to be installed and tightened in place beneath the first lateral arm64before the next adjacent solar panel is installed, to provide enhanced flexibility in installation as well as helping to prevent movement or shifting of the modules in a row during the installation process, as will be discussed further below.

By way of example, the second thickness T2may be in a range of about 60% to 80% of the first thickness T1. In accordance with one example implementation, the bracket32may be 3″ long and 3⅜″ wide, and the mid clamp60may be 1½″ tall and 1½″ wide, with a width of the leg of ¼″, although other dimensions may be used in different embodiments. In an example embodiment, the first thickness T1may be 0.25 inches, while the second thickness T2may be in a range of 0.156-0.1875 inches, although here again other thicknesses may be used in different embodiments. Because of the reduced second thickness T2relative to the first thickness T1, a second solar panel31advantageously may be slid underneath the second lateral arm65after the mid clamp60is already in place over the first solar panel, which would not be possible if the two arms were of the same thickness.

The mid clamps60may advantageously be used to attach the solar panels31to the panel mounting brackets32(or other suitable brackets or rails in different embodiments) independent to the installation of subsequent mounts. This means that each panel31may be tightened and secured before the next adjacent panel is installed, allowing the installer to install each panel exactly where he or she wants it to be secured. This helps to eliminate movement or shifting of panels31, which often occurs as installers are positioning the next panel or module of a series of modules in a row, and therefore helps insure straighter and more efficient installs.

Furthermore, a pair of first set screws66(e.g., 10-32 stainless sharp point set screws) is carried by the first lateral arm64in holes67to be screwed into contact with the first solar panel31, and a second set screw67(e.g., 5/16-18 cup point screws) is carried by the second lateral arm65to be screwed into contact with the second solar panel, as will be discussed further below. In addition, bottom surfaces70,71of the first and second lateral arms64,65may be serrated, scored, or otherwise textured, if desired (seeFIG. 12). This may advantageously help provide enhanced grip as well as electrical grounding.

As described above, the distal end40of the vertical extension36has a fastener channel41therein. A respective fastener75(e.g., a bolt and nut, as shown inFIG. 13) may be used to couple the proximal end62of each mid clamp60to the distal end40of the vertical extension36through a hole76extending vertically through the leg61, as will be discussed further below.

The mid clamp60may also have integrated bonding to meet the applicable bonding requirements (such as UL 2703), and thereby eliminate running mechanical grounding leads from panel to panel. The mid clamp60may accordingly help reduce costly time on the roof, as well as added expense of extra grounding wire and lay in lugs.

An example approach for installing the system30using the mid clamps60on a roof90is now described. As noted above, the panel mounting brackets32may be sealed using either butyl tape or other suitable sealant. By way of example, when using a sealant, the installer may add a liberal amount to the bottom of each bracket32just prior to attaching them to the roof. When using butyl tape, an assistant on the ground may prepare the brackets32ahead of time by pre-applying the tape, for example.

The installer marks the location of the first panel31on the roof and measures over from the edge of the first module the width of the module (e.g., 39⅛″) plus ⅜″ (i.e., 39½″). A mark may be made opposite the location of the first mounting feet32. The perimeter edge mounting feet32may be secured to the outside marks with four #10 deck screws, for example.

Next, the mid clamps60with bolts and kept nuts through the top groove41of each of the mounting feet32opposite the outside edge of the panel31. The bolts may be tightened so the first lateral arm64is snug to the first panel31, and the panel secured with the two set screws66tightened against the panel. By way of example, the fastener75of each mid clamp60may be tightened to 10 ft.-lbs. with a torque wrench77so that the two sharp-point set screws66bite into the frame of the panel31, piercing the anodized coating and securing the panel tight against the mounting feet32(seeFIGS. 14 and 15).

In a next step, the installer may measure over from the frame of the first panel31the width of the panel plus ⅜″ (i.e., 39½″) and make another mark for each of the next feet32(FIG. 16), although other dimensions may be used in different embodiments. The next set of mounting feet32may be centered over the marks and sealed with sealant or butyl tape, and secured with four #10 screws (or other suitable screw) for each location (FIG. 16). Then, a next panel31may be set on the four mounting feet32by sliding it under the second lateral arms65of the first set of mid clamps60, and the second panel may be secured with the mid clamps along the outside leading edge similar to the first panel (FIG. 17).

Next, the set screw67from the mid clamps60of the leading edge of the first panel31may be tightened into the trailing edge of the second panel by turning it clockwise one full turn so that it bites through the anodized coating on the module (FIG. 18), e.g., with an Allen wrench78. This action helps secure the second panel31as well as bond it electrically to the first panel. The process may then continue with each subsequent panel31following the steps described above until the final panel. For the final panel31, the above steps are followed after securing the final two clamps (which may be end clamps50or mid clamps60) to the outer frame edge to secure the outside edge of the final panel.

Electrical grounding connections between rows of feet32may be accomplished by running a wire80(e.g., solid #10 copper wire) from one row to the next, as shown inFIG. 19. By way of example, lugs81(such as Ilsco SGB-4 lay in grounding lugs81or other suitable lugs) may be coupled through the top slot of one mounting foot32and connected to each end panel per row.

In the event that a panel31needs to be removed from the array, the mid clamp60allows this to be relatively easily accomplished without having to remove other panels in the array. First, the electrical leads should be disconnected from the panel31to be removed and the adjacent panels in compliance with the applicable solar module manufacturer's guidelines. The mid clamps60may then be loosened and removed from the leading edge of the panel31to be removed. This is the edge which has the two set screws66of each mid clamp60secured to it. The mid clamps60removed in the previous step may then be turned 180 degrees and reinstalled, insuring the two set screws66on each clamp60are facing toward the opposite panel31being secured. The fastener75may then be tightened to 10 ft.-lbs. of torque (or other suitable value for the given fastener). A conductor79(e.g., solid copper wire) may optionally be secured between one set of mounting feet32per module using lugs such as those described above (FIG. 20) so that there is not a break in the electrical grounding circuit.

As such, it will be appreciated that the mid clamp60advantageously provides for integrated bonding to facilitate electrical grounding between adjacent panels31in a same row, yet without the necessity for running a separate grounding wire between them. Instead, grounding wires may simply be run between mounting brackets in different rows, as described above, to advantageously simplify and expedite the installation process.

It should be noted that the various dimensions provided herein are exemplary, and that other dimensions and sizes may be used in different embodiments. It should also be noted that the mid clamp60may also be used with a variety of different mounting brackets or assemblies, and not just the mounting bracket32.

Many modifications and other embodiments of the invention will come to the mind of one skilled in the art having the benefit of the teachings presented in the foregoing descriptions and the associated drawings, which are provided by way of example. Therefore, it is understood that the disclosure is not to be limited to the specific embodiments disclosed, and that other modifications and embodiments are intended to be included within the scope of the appended claims.