Patent Description:
Solar panels can be secured to rails using over-the-panel clamps and under-the-panel clamps. Over-the-panel clamps typically secure a solar panel to a rail by clamping downward on the top of the solar panel's frame. Over-the-panel clamps come in several styles. These include mid clamps and end clamps. Mid clamps are positioned between two adjacent solar panels. End clamps are positioned on the outside perimeter of the solar panel array.

Under-the-panel clamps typically secure the underside of the inward-facing lower lip, or return flange, of the solar panel frame to the rail. Under-the-panel clamps are also known as solar panel bottom clamps.

Solar panel racking systems (also known as solar panel mounting systems) can use a combination of over-the-panel clamps and solar panel bottom clamps. For example, a solar panel racking system can use over-the-panel mid clamps between solar panels and solar panel bottom clamps under the perimeter edges of the solar panel array.

<CIT> discloses a clamp having a body, a wedged channel nut, and a bolt. The body has a first component extending from the body and configured to engage a module and a second component having a tapered body surface.

<CIT> discloses a mounting system for solar panel assemblies. A solar panel base rail includes one or more alignment stops extending parallel from a horizontal flange of the base rail.

The inventor set out to improve solar panel bottom clamps. As a solar panel racking system designer, he set out to make it easier for the system installers to install and repair solar panel racking systems. He observed that many solar panel bottom clamps require hand tools to install and are not easy to access. He also observed that solar panel bottom clamps that are easy to access are often complex and expensive to fabricate. To the inventor's knowledge, commercially available solar panel bottom clamps are only compatible with slotted rails.

Aspects of the invention are set out in the independent claim appended hereto.

The inventor developed a solar panel bottom clamp that can work with both slotted and slotless rails, can be installed with either hand tools or power tools, is easy to access, simple in design, and relatively inexpensive to manufacture.

The device includes a clamp body and a clamping mechanism that resides at least partially within the clamp body. The clamp body includes a bottom and a pair of sides extending upward from the bottom. The pair of sides includes a corresponding pair of slot-shaped openings. The slot-shaped openings are open on one end, parallel to each other, and extend widthwise along the sides of the clamp body. The clamping mechanism is disposed to selectively narrow the distance between the pair of slot-shaped openings and the top surface of the clamping mechanism.

Expanding upon the principle described above, the clamp body and the slot-shaped openings are sized, shaped, and positioned to receive a rail between the pair slot-shaped openings and the clamping mechanism. The slot-shaped openings are sized and shaped to receive the return flange of the solar panel. As the clamping mechanism is adjusted upward, it presses the rail and the return flange against the upper edge of the slot-shaped openings, securing the solar panel to the rail.

The clamping mechanism includes a threaded fastener. The threaded fastener can engage a movable member that is also threaded and cause the movable member to move up and down, i.e., toward, or away from the slot-shaped openings. The clamping mechanism can alternatively include a threaded fastener, a stationary member, and a movable member. The threaded fastener passes through the stationary member and engages the movable member, which causes the movable member to move up or down, toward, or away from the pair of slot-shaped openings. With the rail received by the clamp body and the return flanges received by the slot-shaped openings as described above, turning the threaded fastener can cause the movable member to move upward, pressing the rail against the return flange and the return flange against the top of the slot-shaped openings.

The inventor built and tested an example, using principles described above, where a threaded fastener engages an unthreaded first wedge and threadedly engages a second wedge. The first wedge is held stationary to the clamp body. As the threaded fastener is turned, depending on the direction, the second wedge is drawn inward and moves upward along the first wedge, or is drawn outward and moves downward along the first wedge. As the threaded fastener moves up the first wedge, it narrows the distance between the top of the clamping mechanism (i.e., top of the second wedge) and the slot-shaped openings. When the rail and return flange are received by the clamp body, as previously described, drawing the second wedge upward along the first wedge presses the rail against the return flange and the return flange against the top of the slot-shaped openings. In this example, the threaded fastener can be adjusted using power tools or hand tools from the edge of the solar panel array. The first wedge, second wedge, and clamp body can be extruded for economy. They can alternatively be cast, molded, 3D printed, or stamped and formed.

The inventor envisions the principles described in this disclosure can be applied to other devices for mounting solar panel return flanges to rails. In one example, the clamping mechanism could include a threaded fastener, a threaded stationary nut, and a lever arm. In another example, the inventor envisions the clamping mechanism could include a threaded fastener, a threaded movable nut, and a compressible member. For example, the compressible member can be a cone-shaped object or a compressible wedge. In yet another example, the inventor envisions the clamping mechanism as a threaded fastener whose body passes into a threaded aperture in the bottom of the clamp body.

In addition, it is the inventor's intent that his concept can encompass a system that includes the solar panels, rails, mounting brackets, as well as the solar panel bottom clamps discussed above. In addition, he envisions this system be applied to residential, commercial, industrial, and utility-scale applications including roof-mounted and ground-mounted systems.

These examples and the above-mentioned advantages are representative and are not meant to limit the inventive concept to the examples given or the discussed advantages. This summary is not exhaustive. Additional features and advantages will be apparent from the Detailed Description, drawings, and claims.

When describing the figures, the terms "top," "bottom," "front," and "side," are from the perspective of a person standing in front of a solar panel assembly. Specific dimensions are intended to help the reader understand the scale of the disclosed material. Dimensions given are typical and the claims are not limited to the recited dimensions. Ordinals such as "first," "second," or "third," are used in this Detailed Description and in the Claims to differentiate between similarly-named parts and do not imply a particular order, preference, or importance. "Optional" or "optionally" is used throughout this disclosure to describe features or structures that are optional. Not using the word "optional" or "optionally" to describe a feature or structure does not imply that the feature or structure is not optional. Finally, the word "or" is used in the ordinary sense to mean an "inclusive or," unless preceded by a qualifier, such as the word "either," that signals an "exclusive or.

The following terms are used throughout this disclosure and are defined here for clarity and convenience.

Solar Panel Bottom Clamp: As defined in this disclosure, a solar panel bottom clamp is a device that secures the return flange of a solar panel frame to a solar panel mounting device. The solar panel mounting device is typically a rail.

Return Flange: As defined in this disclosure, a return flange is the lower lip portion of a solar panel frame that projects inward underneath the solar panel.

<FIG> illustrates a portion of a solar panel assembly <NUM> mounted to a roof <NUM> as typically viewed by an observer from the ground. In this illustration, the portion of the solar panel assembly <NUM> visible from the ground, includes two instances of solar panel <NUM> and two instances of mid clamp <NUM>. The visible portion of each instance of the solar panel <NUM> illustrated, includes frame 102a surrounding a solar cell assembly 102b.

<FIG> illustrates the solar panel assembly <NUM> of <FIG> with the two instances of solar panel <NUM> shown in outline, via dashed lines, to reveal a solar panel racking system <NUM>. The frame 102a of each instance of the solar panel <NUM> includes return flange 102c. The return flange positioned in the front portion of each instance of solar panel <NUM> is hidden from view.

The solar panel racking system <NUM>, as illustrated, includes two instances of mid clamp <NUM>, six instances of roof bracket <NUM>, two instances of rail <NUM>, and four instances of solar panel bottom clamp <NUM>. The solar panel assembly <NUM> is simplified for illustration. Typically, residential, commercial, industrial, or utility-scale solar arrays, include many more solar panels. For example, a <NUM> kW residential array using <NUM> W solar panels could require an array size of forty-two solar panels. A <NUM> kW commercial system could include as many as <NUM> solar panels. Such a commercial system would require hundreds of the mid clamp <NUM>, roof bracket <NUM>, rail <NUM>, and solar panel bottom clamp <NUM>.

The solar panel racking system <NUM>, as illustrated in <FIG>, includes solar panel bottom clamp <NUM> mounted on the outside perimeter of the solar panel array <NUM> of solar panel assembly <NUM>. Solar panel bottom clamp <NUM>, as built by the Applicant, will be described in <FIG> with associated components discussed in <FIG>. Prophetic examples of solar panel bottom clamps are illustrated in <FIG>.

This General Concepts section describes general principles. For simplicity, these general principles are discussed in terms of <FIG>, but can be applied to the other figures and examples in the disclosure.

<FIG> show, in side view, the solar panel bottom clamp <NUM> of <FIG>. The solar panel bottom clamp <NUM> includes a clamp body <NUM> and a clamping mechanism <NUM>. The clamping mechanism <NUM> can be positioned at least partially within the clamp body <NUM>. For example, in <FIG>, a portion of the clamping mechanism <NUM> is illustrated as extending beyond the clamp body <NUM>.

In <FIG>, the clamp body <NUM> includes a bottom and a pair of sides extending upward from the bottom. First side 109a and second side 109b extend upward from bottom 109c. The pair of sides includes a corresponding pair of slot-shaped openings. First side 109a includes first slot-shaped opening 109d and second side 109b includes second slot-shaped opening 109e. The slot-shaped opening can be parallel to each other. The first slot-shaped opening 109d is illustrated as open on one end and extending widthwise (i.e., along the width) into the first side 109a. The second slot-shaped opening 109e is illustrated as open on one end and extending widthwise into the second side 109b. <FIG> also illustrate the first slot-shaped opening 109d extending widthwise into the first side 109a and the second slot-shaped opening 109e extending widthwise into the second side 109b.

Referring to <FIG>, a construction line <NUM> between the upper edge 109f of first slot-shaped opening 109d and the upper edge <NUM> of second slot-shaped opening 109e illustrates that they are positioned parallel to each other on first side 109a and second side 109b, respectively. The construction line <NUM> is perpendicular to first side 109a and second side 109b. The clamping mechanism <NUM> is shown disposed to selectively narrow the distance <NUM> between a top portion 110a of the clamping mechanism <NUM> and the pair of slot-shaped openings. In <FIG>, for example, the distance <NUM> between the clamping mechanism <NUM> and the pair of slot-shaped openings is represented as a distance d1. In <FIG>, selectively engaging the clamping mechanism <NUM> narrows this to a distance d2. Distance <NUM> is illustrated to represent the distance between the top portion 110a of the clamping mechanism <NUM> and construction line <NUM>, which passes through the upper edges of the pair of slot-shaped openings.

The pair of slot-shaped openings, being open on one end, allows them to receive a planar surface that is wider than the width of the clamp body <NUM>, for example, the return flange 102c of <FIG>. Referring to <FIG>, the pair of slot-shaped openings, first slot-shaped opening 109d (<FIG>) and second slot-shaped opening 109e (<FIG> and <FIG>) receives the return flange 102c (<FIG>). In <FIG> and <FIG>, the solar cell assembly 102b, the return flange 102c, and the upper portion of the clamp body <NUM> that is positioned behind the frame 102a of the solar panel <NUM>, is represented by dashed lines. In <FIG> and <FIG>, the front of the solar panel <NUM> is cutaway to reveal the frame 102a, the solar cell assembly 102b, and the return flange 102c. The clamping mechanism <NUM> is hidden behind the first side 109a and illustrated in dashed lines.

Referring to <FIG>, the clamp body <NUM> is sized and shaped to receive the rail <NUM> between the pair of slot-shaped openings and the top portion 110a and enclose the rail <NUM> between the bottom 109c, the pair of sides, and optionally the top 109i.

In <FIG> and <FIG>, the clamping mechanism <NUM> is selectively engaged (i.e., adjusted) to widen the distance between the top portion 110a of the clamping mechanism <NUM> and the pair of slot-shaped openings. This creates a gap between the upper edges of the pair of slot-shaped openings, upper edge 109f (<FIG> and <FIG>) and upper edge <NUM> (<FIG>), and the top of the rail <NUM>, and allows the return flange 102c and the rail <NUM> to move relative to one another.

In <FIG> and <FIG>, the clamping mechanism is adjusted to narrow the distance and close the gap between the top portion 110a of the clamping mechanism <NUM> and the pair of slot-shaped openings. The clamping mechanism <NUM> presses upward against rail <NUM>. The rail <NUM> and the return flange 102c together are pressed against the upper edge 109f (<FIG> and <FIG>) and upper edge <NUM> (<FIG>) of the pair of slot-shaped openings. This clamps the rail <NUM> and the return flange 102c to each other, clamping the solar panel <NUM> to the rail <NUM>.

In general, the clamping mechanism can include a movable member. It can alternatively include a threaded fastener and a movable member. It can include a threaded fastener, a stationary member, and a movable member. In the last instance, the threaded fastener can either threadedly engage the stationary member and non-threadedly engage the movable member or the threaded fastener can threadedly engage the movable member and non-threadedly engage the stationary member. In the variations described in this paragraph, the movable member, through selective engagement, narrows the distance between the pair of slot-shaped openings and the top surface of the movable member. Examples of each will be discussed later in this Detailed Description.

Applying at least some of the concepts discussed in this section, a solar panel bottom clamp can be constructed inexpensively and with few components. These components can be extruded for cost and strength. Alternatively, the can be stamped and formed, cast, or 3D printed. The components can be made from aluminum, steel, plastic, or any material with sufficient strength to clamp and support a solar panel to a roof or ground-mount structure and capable of withstanding the environmental conditions typical of solar panel racking systems.

The inventor envisions that the principles discussed in this section can be applied to a wide range of solar panel bottom clamps, examples of which, are discussed below.

Now we will discuss the particular implementation of the solar panel bottom clamp <NUM> illustrated in <FIG> as well as discussion of associated components in <FIG>.

Referring to <FIG>, the solar panel bottom clamp illustrated includes the clamp body <NUM> and the clamping mechanism <NUM>. The clamp body <NUM> is shown with slot-shaped openings, first slot-shaped opening 109d and second slot-shaped opening 109e, open on one end, and extending widthwise into corresponding pair of sides, first side 109a and second side 109b, respectively, as previously described. The clamping mechanism <NUM> includes a stationary member, a movable member, and a threaded fastener <NUM>. A first wedge <NUM> is held stationary within the clamp body <NUM>, and a second wedge <NUM> is made movable up along the first wedge <NUM> by threaded engagement with the threaded fastener <NUM>. Referring to <FIG>, this causes the distance <NUM> between the pair of slot-shaped openings and the top portion 110a of the clamping mechanism <NUM> to narrow.

Referring to <FIG> and <FIG>, the second wedge <NUM>, made movable along the first wedge <NUM> by threaded engagement with the threaded fastener <NUM>, presses the rail <NUM> upward against the return flange 102c. The first wedge <NUM> is held stationary within the clamp body <NUM>, for example, by crimping, swaging, welding, adhesives, threaded fasteners, or integrally forming the first wedge <NUM> with the clamp body <NUM>. The inventor envisions the first wedge <NUM> can be held stationary within the clamp body <NUM> by any suitable way of attachment that can withstand the typical day-to-day operations and environmental conditions of a solar panel racking system.

Referring to <FIG>, the first wedge <NUM> includes a through-aperture 114a. The through-aperture 114a can be unthreaded and elongated. This allows the threaded fastener <NUM> (see <FIG>) to pass through the first wedge freely and change the angle of engagement with the first wedge <NUM> as the second wedge moves up and down along the first wedge top surface 114b.

Referring to <FIG>, the second wedge <NUM> includes a threaded aperture 115a that passes through the first side surface 115b and the second side surface 115c of the second wedge <NUM>. Referring to <FIG>, the top surface 115d of the second wedge <NUM> is shown as slotted, however, it can also be flat or planar.

Referring to <FIG>, the first wedge <NUM> and the second wedge <NUM> are positioned between the pair of sides, first side 109a and second side 109b. Through-aperture 114a and threaded aperture 115a are likewise positioned between the pair of sides. The threaded fastener <NUM> engages the stationary member (i.e., the first wedge <NUM>) and the movable member (i.e., the second wedge <NUM>) between the pair of sides and widthwise along the pair of sides.

<FIG> illustrate an example of a solar panel bottom clamp <NUM> that utilizes the clamp body <NUM> and the clamping mechanism <NUM>. Referring to <FIG>, and <FIG>, the clamping mechanism <NUM> includes a threaded fastener <NUM> that threadedly engages a stationary member, i.e., stationary nut <NUM>, and a movable member, i.e., lever arm <NUM>. Referring to <FIG>, the clamping mechanism <NUM> is at least partially positioned within the clamp body <NUM> between the first side 109a and the second side 109b. Referring to <FIG>, and <FIG>, lever arm <NUM> pivotally engages the clamp body <NUM> through apertures in the sides of the clamp body <NUM>. Referring to <FIG>, the first aperture within first side 109a is hidden from view, while the second aperture <NUM> is shown in second side 109b.

Referring to <FIG>, the stationary nut <NUM> is secured to the clamp body <NUM>. The clamp body <NUM> and the stationary nut <NUM> can have complementary flanging, as illustrated, to create a tongue and groove. The stationary nut <NUM> can be secured to the clamp body <NUM> by crimping, swaging, welding, adhesive, or secured by one or more threaded fasteners. Alternatively, the stationary nut <NUM> could be eliminated by integrally forming a lower wall in the clamp body <NUM>, in place of the stationary nut <NUM>. In this case, with the stationary member eliminated, the clamping mechanism <NUM> would include the threaded fastener <NUM> and a movable member, i.e., the lever arm <NUM>.

Referring to <FIG>, the threaded fastener <NUM> threadedly engages the stationary nut <NUM>. As the threaded fastener <NUM> moves inward through the stationary nut <NUM>, it presses against the lever arm <NUM>, which is wedge shaped, and pushes the lever arm <NUM> upward. This narrows the distance <NUM> between the top portion 120a of the clamping mechanism <NUM> (i.e., the top portion of the lever arm <NUM>), and the upper edges of the pair of slot-shaped openings. <FIG> shows the upper edge 109f of the first slot-shaped opening 109d. For upper edge 109f of the first slot shaped opening 109d and the upper edge <NUM> of the second slot-shaped opening 109e in relation to the lever arm <NUM>, see <FIG>.

<FIG> illustrate another example of a solar panel bottom clamp <NUM> with clamping mechanism <NUM> and clamp body <NUM>. The clamping mechanism <NUM> includes a threaded fastener <NUM>, a stationary member, i.e., stationary nut <NUM>, a movable member, i.e., compressible member <NUM>, and a threaded retainer <NUM>. The stationary nut <NUM> can be secured to the clamp body <NUM> as described for examples <NUM> and <NUM>. The threaded retainer here is shown as a threaded nut, but can be other types of threaded retainers capable of compressing the compressible member <NUM>. The compressible member <NUM> is illustrated as a cone, but can also be a wedge, or other shapes that are wider on one end than the other. As the compressible member <NUM> is compressed, the taller end is drawn into the clamp body <NUM>. This shortens the distance between the top surface 130a of the clamping mechanism <NUM> (i.e., the top of the compressible member <NUM>) and the upper edges of the slot-shaped openings. As illustrated, this is upper edge 109f and upper edge <NUM> of the first slot-shaped opening 109d and the second slot-shaped opening 109e, respectively. With the rail received by the clamp body <NUM> and the return flange received by the pair of slot-shaped openings, as previously discussed, drawing the taller end of the compressible member <NUM> into the clamp body <NUM> would press the rail against the return flange and secure the solar panel to the rail.

The compressible member <NUM> is typically made from ethylene propylene diene monomer rubber (i.e., EPDM), natural rubber, or a synthetic rubber such as polychloroprene (i.e., neoprene). The compressible member <NUM> can be made from any compressible material that can withstand the environmental conditions typical of a solar panel installation and has sufficient resistance to deflection under the load of the solar panel, to clamp the solar panel in place.

In the previous examples, the threaded fastener was positioned horizontally with the head of the fastener facing away from the solar panel array. This allows the solar panel bottom clamp to be easily adjusted using a power tool. There may be instances where it is desirable to adjust the solar panel bottom clamp from below. An example of this, could be a ground-mounted solar panel array where the installer has access vertically from below rather than horizontally from the sides. <FIG> illustrate an example where the solar panel bottom clamp <NUM> that can be adjusted from below. The solar panel bottom clamp <NUM> includes clamp body <NUM> and a clamping mechanism <NUM>. Here the clamping mechanism <NUM> is a threaded fastener <NUM> that threadedly engages a threaded aperture 147i in the bottom 149c of the clamp body <NUM>.

As the threaded fastener <NUM> threadedly engages the clamp body <NUM>, it moves into the clamp body <NUM> and closes the distance between the top portion 140a of the clamping mechanism <NUM> (i.e., the end of the threaded fastener <NUM>) and the pair of slot-shaped openings (i.e., slot-shaped opening 149d and slot-shaped opening 149e). If a rail and return flange were received in the clamp body <NUM> as previously described, tightening the threaded fastener <NUM> would press the rail up against the return flange and clamp the return flange to the rail.

In the examples given, the clamp body <NUM> of <FIG>, <FIG> as well as clamp body <NUM> of <FIG> are enclosed on four sides. For example, in <FIG> and <FIG>, the pair of sides, first side 109a and second side 109b extend downward from opposite edges of top 109i. The pair of sides, first side 109a and second side 109b similarly extends upward from the bottom 109c.

<FIG> illustrate the clamp body <NUM> that is open on the top. The clamp body includes a pair of sides, first side 159a and second side 159b extending upward from the bottom 159c. The pair of sides includes a corresponding pair of slot-shaped openings, slot-shaped opening 159d and slot-shaped opening 159e. Slot-shaped opening 159d and slot-shaped opening 159e are open on one end so they can receive a return flange of a solar panel in the same way as described for <FIG>.

The clamp body <NUM> can be readily substituted for clamp body <NUM> of <FIG>, <FIG> and clamp body <NUM> of <FIG>. As an example, <FIG> illustrates solar panel bottom clamp <NUM> with clamp body <NUM> and clamping mechanism <NUM> of <FIG>. Similarly, the clamp body <NUM> can be used with clamping mechanism <NUM> of <FIG>, clamping mechanism <NUM> of <FIG>, and clamping mechanism <NUM> of <FIG>.

The clamp body <NUM> of <FIG> and <FIG>, clamp body <NUM> of <FIG>, and clamp body <NUM> of <FIG> include sides that are indented inward before terminating at the bottom of the clamp body. For clamp body <NUM> of <FIG> and <FIG>as well as clamp body <NUM> of <FIG>, this is to help capture the stationary member of the clamping mechanism, i.e., the first wedge <NUM> of <FIG>, <FIG>, <FIG>, the stationary nut <NUM> of <FIG> and <FIG>, and the stationary nut <NUM> of <FIG>. In <FIG>, this indented portion is solid, allowing for a longer and stronger threaded aperture. The clamp body is not limited to these configurations illustrated. The clamp body can be any shape that is capable of receiving a rail below the pair of slot-shaped openings in their corresponding pair of sides of the clamp body, capturing a solar panel return flange in the slot-shaped openings, and enabling a clamping mechanism to press the rail and return flange against the upper edges of the slot-shaped openings.

For example, the clamp body could have a rectangular cross section. The clamp body could alternatively have a u-shaped cross section with an open top. In either case, the stationary member of the clamping mechanism could be secured to the bottom of the clamp body. For example, the clamping mechanism could be captured in grooves or channels in the bottom of the clamp body. The inside surface of the clamp body could also be flat. The stationary member could be secured to the clamp body by threaded fasteners extending upward through the bottom of the clamp body and into the stationary member or downward through the stationary member into the bottom of the clamp body. The stationary member could also be secured to the bottom by adhesive or by permanent tape.

Claim 1:
A device for securing a solar panel (<NUM>) to a rail (<NUM>), the solar panel (<NUM>) including a frame (102a) and a return flange (102c) , the return flange (102c) being a lower lip portion of the frame that projects inward underneath the solar panel (<NUM>), comprising:
a clamp body (<NUM>) that includes a bottom (109c), and a first side (109a) and a second side (109b) each extending from the bottom (109c), a pair of slot-shaped openings (109d, 109e) for receiving the return flange (102c) of the solar panel (<NUM>), the pair of slot-shaped openings (109d, 109e) including a first slot-shaped opening (109d) that is open on a first end and extends widthwise into the first side (109a) and a second slot-shaped opening (109e) that is open on a second end and extends widthwise into the second side (109b); and
a clamping mechanism (<NUM>) at least partially positioned within the clamp body (<NUM>), the clamping mechanism (<NUM>) includes a threaded fastener (<NUM>) and a movable member (<NUM>);
wherein the clamp body (<NUM>) is structured to receive the rail (<NUM>) between the pair of slot-shaped openings (109d, 109e) and the clamping mechanism (<NUM>), and the movable member (<NUM>) made movable by the threaded fastener (<NUM>) is configured to selectively press against the rail (<NUM>) and clamp the return flange (102c) against the rail (<NUM>).