Patent Application
20130091786
The present application relates generally to an attachment system and more particularly to a photovoltaic panel fastening system for a building.
Conventional photovoltaic or solar panels are mounted to roofs of buildings through screw-in clips or the like. Examples of such conventional devices are disclosed in U.S. Patent Publication No. 2011/0088740 entitled “Photovoltaic Panel Clamp” which published to Mittan et al. on Apr. 21, 2011, and U.S. Pat. No. 6,672,018 entitled “Solar Module Mounting Method and Clip” which issued to Shingleton on Jan. 6, 2004, both of which are incorporated by reference herein. Such conventional methods cause the installer to juggle many loose fasteners while simultaneously holding heavy solar panels and/or roof mounting components, often on a tilted metal roof in unpleasant weather conditions. Furthermore, such traditional multi-piece screw or bolt arrangements take considerable time to install while also having inconsistent installation torque values, especially in the common situation where many of these solar panel mounting devices are required for each roof.
In accordance with the present invention, a fastening system is provided. In another aspect, a hook fastens a photovoltaic panel assembly to a building roof. Another aspect employs catches that removeably attach an auxiliary component, such as a solar panel frame, to a building in hinge and slide motions for engagement of the catches. A method of installing a fastening system is additionally provided.
The present attachment system is advantageous over traditional devices. For example, in one aspect, a simplified installation motion is employed to engage an auxiliary component, such as a photovoltaic panel assembly, with a mounting hook. In an aspect of the present attachment system, an auxiliary roof component is quickly and easily secured to a building roof in a fast manner without requiring the installer to juggle multiple parts. In another aspect, a catch of the fastening system is very inexpensive to manufacture and assemble. Furthermore, the present fastening system is preassembled to a building roof via an easy to install roof clamp, prior to assembly of the solar panel assembly to the fastening system. The catch of the present attachment system ideally allows for tolerance variations and part expansion. Additional advantageous and features of the present invention will become apparent in the following description and appended claims, taking in conjunction with the accompanying drawings.
FIGS. 2 and 4-6 depict roof clamp 31 attached to seam 25 of roof 23. Roof clamp 31 includes a saddle 41, a roof seam-engaging wedge 43, and an elongated shaft or securing member 45. A generally C-shaped leaf spring 47 has pins at one end attached to holes in saddle 41, and is trapped between a head of shaft 45 and wedge 43 at the other end. Spring 47 serves to retain wedge 43 to saddle 41 in a pre-assembled state prior to seam installation while also biasing wedge 43 into a clamping position toward a top wall of saddle 41 and seam 25. Thus, camming action of roof seam-engaging wedge 43 along diagonal internal surfaces of saddle 41 compresses roof clamp 31 to seam 25. Tightening of a nut 49 onto shaft 45 secures wedge 43, and thus roof clamp 31, to the seam. When an installer manually pushes a proximal exposed end of shaft 45 (opposite its head) toward saddle 41, against the biasing force of spring 47 and through an oversized hole in the top wall of the saddle, wedge 43 is pushed to an open position allowing seam access into an opening of saddle 41. Notably the same shaft 45 that secures roof clamp 31 to roof 23 also secures an auxiliary-retaining device, such as catch 33, to roof 23 along a top surface of saddle 41.
Saddle 41, roof seam-engaging wedge 43, shaft 45, spring 47 and optionally catch 33, are pre-assembled prior to placing roof clamp 31 in the proximity of roof seam 25. “Pre-assembled” for the clamp refers to the components being attached as a single unit such that shaft 45, and optionally a very loose engagement of nut 49 (so as to provide lost motion movement of the spring and wedge relative to the saddle), keep them attached together. This can be achieved either on the ground at the work site, at a remote site, or at the factory in which roof clamp 31 is manufactured. When wedge 43 is retracted to trap seam 25 between an inner foot of the wedge and the inner opening edge of saddle 41, a portion of shaft 45 extends beyond the top surface of saddle 41 such that the proximal threaded end of shaft 45 also provides an attachment point for catch 33 and nut 49. The roof clamp preferably attaches to the roof seam due to lateral seam compression of the wedge but without seam piercing or side-mounted threaded screws.
Referring now to
A slotted aperture is centrally provided in bottom wall 101 of catch 33 to receive the threaded end of shaft 45 for nut attachment thereto. Furthermore, at least two tabs 121 are downwardly bent from bottom wall 101 of catch 33. These tabs 121 assist in orienting catch 33 relative to saddle 41 of roof clamp 31 prior to full securing of nut 49 on shaft 45. Catch 33 has a generally U-shape when viewed from its end, such as in
Catch 33 advantageously provides a hinge and slide fastening motion for photovoltaic panel assembly 27. More specifically, the installer first couples each of the preassembled roof clamps 31, including catches 33, onto roof seams 25 in a single top down, manually actuated motion; spring 47 will thereby cause the camming action to laterally move wedge 43 into compression against seam 25. Nuts 49 are then rotatably tightened on only the hinge side fastening systems 29, preferably near the lower edge of the tilted roof 23 first (the rightmost system 29 shown in
Finally, an alternate embodiment catch or mounting bracket 233 is shown in
While various aspects of the present fastening system have been disclosed, it should be appreciated that modifications can be made. For example, the present accessory mounting brackets or catches can be secured to conventional roof clamps such as those disclosed in the following U.S. Pat. Nos. 7,758,011 entitled “Adjustable Mounting Assembly for Standing Seam Panels” which issued to Haddock on Jul. 20, 2010; 7,386,922 entitled “Snow-Guard Clamping Unit” which issued to Taylor et al. on Jun. 17, 2008; and 5,715,640 entitled “Mounting Device for Controlling Uplift of a Metal Roof” which issued to Haddock on Feb. 10, 1998; except many of the present advantages will not be realized. These patents are incorporated by reference herein. Moreover, more or less hooks and barbs can be attached to a single bracket although some of the present advantages may not be obtained. It is also envisioned that the fastening system is attachable to an exterior side of a building or a ground-based structure, although various advantages may not be achieved. Furthermore, the catches can be injected molded from a polymer, cast from aluminum, or otherwise differently manufactured, however, various advantages may not be obtained. The frame can also have a different shape although certain advantages may not be observed. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but, where applicable, are interchangeable and can be used in a selected embodiment, even if not specifically shown or described. Such variations are not to be regarded as a departure from the disclosure, and all such modifications are intended to be included within the scope of the present invention.
