Pivot-Fit Frame, System and Method for Photovoltaic Arrays

Abstract

A system and apparatus are disclosed including PV modules having a frame allowing quick and easy assembling of the PV modules into a PV array in a sturdy and durable manner. In examples of the present technology, the PV modules may have a grooved frame where the groove is provided at an angle with respect to a planar surface of the modules. Various couplings may engage within the groove to assemble the PV modules into the PV array with a pivot-fit connection. Further examples of the present technology operate with PV modules having frames without grooves, or with PV modules where the frame is omitted altogether.

Description

CROSS REFERENCES[0001]The present application is a continuation-in-part of copending application Ser. No. 12 / 830,249, filed Jul. 2, 2010, which claims priority to Provisional Patent Application No. 61 / 270,122, filed Jul. 2, 2009; Provisional Patent Application No. 61 / 255,004, filed Oct. 26, 2009; and Provisional Patent Application No. 61 / 351,586, filed Jun. 4, 2010. This application also claims priority to U.S. Ser. No. 13 / 351,397, filed Jan. 17, 2012, which is a continuation of Ser. No. 12 / 594,935 filed Oct. 6, 2009, now U.S. Pat. No. 8,109,048, issued Feb. 7, 2012. This application also claims the benefit of U.S. Provisional Patent Application Ser. No. 61 / 445,042, filed Feb. 22, 2011. The foregoing applications are incorporated by reference in their entirety as if fully set forth herein.BACKGROUND[0002]Photovoltaic (PV) arrays are formed by mechanically linking together PV modules into an array. Most PV module coupling systems require the time-consuming use of multiple small faste...

AI Technical Summary

Benefits of technology

[0008]Disclosed herein is a system and method for quickly and easily assembling PV modules into a PV array in a sturdy and durable manner. In some embodiments, the PV modules may have a grooved frame where the groove is angled into the frame with respect to the planar surface of the modules. Various components may engage within the angled groove to assemble the PV modules into the PV array using what may be referred to as a pivot-fit connection between the components and angled groove. One type of component is a leveling foot which in some embodiments includes a foot mounted to a support surface and a coupling affixed to the foot. The coupling of the leveling foot may have a male component such as a tongue for coupling within the groove. In order to mount a PV module to the leveling foot, the module is seated on the tongue and rotated down until the angle of the groove substantially aligns with the axis of the tongue. The groove may then seat at least partially over the tongue. To complete the pivot-fit connection, the PV module is simply pivoted down to its final angular orientation in the PV array. This final rotation causes bearing portions in the groove to bear against the tongue to restrain the PV module against upward or downward movement. The coupling may still allow for adjustment of the PV module position in the plane of the PV array to account for tolerance variations.

[0013]Another embodiment relates to a photovoltaic module having a frame adapted for connection to an adjacent photovoltaic module by a coupling and defining a reference plane when connected to the adjacent photovoltaic module. The module includes a first bearing portion; and a second bearing portion; wherein said module is adapted to pivotally engage with said coupling at a position along a length of said frame, said length being substantially parallel with said reference plane, said second bearing portion offset from said first bearing portion in a direction substantially parallel to said reference plane and perpendicular to said length, said first and second bearing portions adapted to allow variable positioning of said photovoltaic module relative to said adjacent photovoltaic module in a direction substantially parallel with said reference plane and perpendicular to said length.

Problems solved by technology

Most PV module coupling systems require the time-consuming use of multiple small fasteners.

High part count and slow installation time is a major barrier to reducing PV system costs and adoption.

First, neither of these methods can adequately account for variations in the dimensions of PV modules and couplings due to manufacturing tolerances. PV modules typically vary by approximately ±0.10″ along the length and / or width dimension. When multiple modules are formed into columns in the north-south direction of the PV array, it is critical that any dimensional variations from one module in the column not carry forward to the next module in the column, as the dimensional variations will add up over the length of the column and result in significant dimensional differences from one column to the next. Likewise, the same problem exists with east-west rows of PV modules. This problem, frequently referred to as tolerance take-up, is solved in rail-based systems by spacing the modules in a column more or less from each other on top of mounting rails so that the next module in the column is properly positioned and / or by only linking modules to the rails along one axis, either east-west or north-south. However, in rail-free systems, a PV module is structurally connected to the next module in both the north-south direction and the east-west direction. Thus, if the seams between adjacent east-west modules do not line up because of compounded north-south dimensional variations, then it may be impossible to complete the installation of an array. In other systems compounded east-west variations may cause problems along the north-south axis. Press-fit and hook-type connections do not adequately address or solve the problem of tolerance variations.

Second, press-fit and hook-type connections do not provide a reliable electrical ground bond between adjacent PV modules. Hook-type connections are inherently loose-fitting and thus incapable of providing a consistent, low-resistance ground bond that will withstand weather conditions over time. Similarly, a press-fit connection does not provide a reliable ground bond unless the materials are deformed enough in the connection. In practice, too much force is required to achieve such deformation with standard PV module frame materials such as aluminum, thereby eliminating any time and cost savings that might have occurred since a heavy-duty tool would be required to deliver the force needed for the deformation.

Third, press-fit and hook-type systems cannot reliably provide a strong, durable connection between mating male and female parts. In order to facilitate a quick and easy connection, the female receiving portion in the connection is made wider than the male connecting portion. This results in a loose or unstable connection, which is vulnerable to loosening over time as the PV modules experience mechanical stress due to wind and snow loads.

The reason is that production of tight tolerance PV modules and couplings is very expensive.

In order to accelerate the adoption of solar power, it is necessary to reduce the cost of solar arrays, thus increased costs for tight tolerance parts is not a viable option in the market.

Other limitations of the related art will become apparent to those of skill in the art upon a reading of the specification and a study of the figures.

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