Patent Publication Number: US-2012045983-A1

Title: Solar Powered Active Roof Ridge Vent

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS: Not Applicable 
     FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT: Not Applicable 
     SEQUENCE LISTING OR PROGRAM: Not Applicable 
     BACKGROUND 
     1. Field 
     This invention relates to roof vents, and more specifically to roof ridge vents. 
     2. Prior Art 
     In areas of warmer climates, the attic spaces of homes or buildings tend to accumulate air much warmer than the ambient environment. The warm air in the attic then drives up the temperature of the home or for homes with air conditioners the cooling load on the air conditioning system of the home, thus increasing energy cost to the home owner. Attic ventilation is known to play an important role in reducing the heat transferred to the interior volume of the home especially in homes with inadequate attic insulation. Many techniques, systems, and devices, some passive, some active, have been developed for ventilation of the attic spaces of homes. Passive systems include passive attic vents, ridge vents and soffit vents. Passive ridge vents have become the most common passive solution to attic ventilation on new homes and new roof installations due to ease of installation and low cost. The passive ridge vent systems are placed over an opening at the upper ridge of a roof. The airflow moves through the attic via convection (hot air rising to the towards the ridge), flows around the ridge beam, through the slot, then turns over the roofline and flows through vents a short distance away. The limitations of the passive device are that they use natural convection and thus do not drive down attic temperatures as much as an active system, which may take advantage of natural convection but also augment the air flow with a powered device. Active systems, meaning a powered device is used to forcibly flow air to or from the attic space, include acreage deck mounted power fans (both grid powered and solar powered), wind powered turbines, gable louvers in combination with an attic exhaust fan, ridge vent outlet mounted impellers, large two piece ridge slot interior mounted impellers (for roofs without ridge beams) and sub-ridge mounted fan assemblies. 
     Active solutions to the high attic temperature problem can generally produce lower attic air temperatures. Active solutions currently proposed, on the market and in prior art have several chief impairments limiting their effectiveness and ubiquitousness. The main impairments of prior art outlined here include difficulty in installation, aesthetic inadequacy, common roof type incompatibility, and cost. Other miscellaneous inadequacies discussed include inefficiency and debris ingestion. 
     A critical driving factor in determining the implementation of active attic ventilation by contractors, homebuilders or the average home owner/do-it-yourselfer is the difficulty of installation and complexity of installation of the active device. All of the proposed active solutions described by prior art fall short of the preferred embodiment described here in this regard. Of the active solutions proposed in prior art many require roofing shingle removal and cutting a pass through in the decking of the rooftop. Many require wiring and associated electrical components to be installed to receive power from the home or buildings power source. Such installations may require a certified electrician. Others forms of prior art require installation of multiple components inside and outside of the attic space. Accessing the ridge area of many attics from the inside can be very difficult due to reach and interior structural member interference. The installation factors described are difficult, overly complicated and require some carpentry or electrician expertise. All of these reasons contribute substantially to the hesitance of the average do-it-yourselfer to endeavor such a project. The complexity involved with installation of existing prior art also deters contractors and homebuilders from use. 
     Many active solutions are also not aesthetically pleasing, forming a large protuberance on the acreage areas of a rooftop&#39;s decking. Such protuberances limit the device&#39;s installation locations to positions on the rooftop out of view of the front the home or building. Wherever installed, they create discontinuity in the profile of the home or buildings roofline which diminishes the aesthetic appeal of the home. Aesthetic appeal directly correlates to home value. Maximizing appeal is a great advantage to the homeowner. 
     Some of the active attic ridge ventilation solutions in prior art are not compatible with roofs with a ridge beam or ridge board. This is because many proposed and patented solutions require there to be a void space beneath the roof ridge&#39;s roofline for placement of the active device (e.g. Impeller) and/or an air sealer. Since a ridge board is a common structural roof element that occupies the space at the apex of a roof just beneath the roof ridge&#39;s roofline, compatibility with such an element ensures that the active device&#39;s potential for future use is maximized. 
     Some proposed active solutions are not attractive to the consumer due to their expense. The cost of proposed solutions is in some cases relatively high due to complexities in the design of the device and in the cost associated with installation of the device (previously discussed). For example, some prior art includes complex electrical controllers for managing the active devices. Such control may marginally enhance efficiency of the device but consequently drives up the cost of the device to the consumer. Higher initial device cost makes the device less attractive to the consumer. 
     The added complexity also increases the power demands of the device, prohibiting the effective use of a solar panel as the sole source powering the device. 
     For prior proposed solutions involving impellers or other active devices placed at the ridge vent outlet, difficulty with debris ingestion, exposure of moving parts to the elements, inherent inefficiencies with impeller fan designs driving the need to provide grid derived power to the device and impeller device size limitations due to positioning are all challenges present. 
     SUMMARY 
     The preferred embodiment of this invention employs a panel, referred to as the main panel, replicating the look of a passive ridge vent panel, having a laterally flexible section but with edge extremities that enable sealing to the roofline and to adjacent ridge mounted panels. The panel has holes cut at the apex at which axial fans are installed. The fans are shielded from precipitation, debris, and other menaces of the natural environment by a flexible shroud. The shroud surrounds the fan area forming a cavity in which the fan drawn air flows and mimics the appearance of a roof ridgeline. The shroud has vents present to allow the fan drawn air to flow to the ambient environment. 
     An alternate embodiment of the invention includes similar elements such as a main panel and axial fans but also includes structural members that are mounted to the main panel extending upwards and attached to a solar panel. The structural elements have movable joints to facilitate the movement of the main panel&#39;s edges during rooftop installation. The solar panel resides above the axial fans protecting them from the natural environment. At the periphery of the solar panel&#39;s bottom edge, a shroud extends down to the main panel surrounding and enclosing the fans. The shroud has a vent in it to allow attic-born fan drawn air to flow to the ambient environment. The shroud is flexible on 2 sides to allow bending of the main panel during roof top installation. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is an orthogonal view of the preferred embodiment 
         FIG. 2  is a cut away diagram of preferred embodiment performing function 
         FIG. 3  is a view of the preferred embodiment installed on the roof ridgline of a home 
         FIG. 4  is an orthogonal view of an alternate embodiment 
         FIG. 5  is a cut away diagram of an alternate embodiment performing function 
         FIG. 6  is a view of an alternate embodiment installed on the roof ridgline of a home 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Preferred Embodiment 
       FIG. 1  shows the ventilation apparatus according to the preferred embodiment of the invention. As shown, the apparatus includes a rectangular panel, the main panel, ( 23 ) with a laterally flexible section allowing the panel to be installed over, to cover and seal the apex of a roof in which the upper section of the decking has been removed to allow air flow through the ridge. The laterally flexible panel is sealed along its edges using standard flexible sealing material to promote airflow through the active portion of the device ( 133 ). Holes are cut in to the laterally flexible panel&#39;s central section to allow for the installation of a series of axial fans ( 53 ) enabling them to extract air ( 113 , 63 ) from beneath the panel and exhaust it into the panels upper cavity formed by a flexible shroud ( 43 ). The fans are held in position on the main panel with standard fasteners. The flexible shroud ( 43 ) forms a cavity above the flexible main panel in which the hot exhaust air flows ( 113 ). The shroud serves to protect the fans from precipitation, debris and mimics the roofline of the home. The shroud ( 43 ) itself is also flexible allowing it to flex with the main panel ( 23 ) during installation. The shroud is of sufficient consistency to allow for standard roofing shingles to be attached via standard fasteners if desired. The wiring for powering the fans is bundled and run along the length of the flexible panel ( 83 ). The bundle runs to a thermostat ( 153 ) and from there extends to an electrical box ( 153 ) beneath a solar panel ( 143 ), which is mounted to the main panel ( 163 ). The thermostat prevents power flow to the axial fans at cooler ambient temperatures. The flexible shroud that forms the secondary air collection cavity above the main panel is fastened to the main panel by a standard fastener type ( 33 ). The flexible shroud has portions removed ( 73 ) along the edge interface with the main panel to form external vents. The removed portions are covered with a fine mesh screen to preclude the entrance of debris. The vents formed by the removed portions and the main panel permit the air removed from the attic to be flowed to the ambient environment. For installation the main panel is fastened over the roof ridge using standard fasteners ( 123 ). The main panel is fastened to the roof top decking over the existing shingle ( 13 ) which are held in pace by decking fastened to the rafters ( 93 ). The axial fans are suspended over the ridge&#39;s ridge beam/ridge board ( 103 ) in the ridge opening ( 173 ) allowing air to flow from the attic space through the ridge opening, through the fan, into the collection cavity over the main panel formed by the shroud and subsequently out through the mesh covered vents in the shroud to the ambient environment.  FIG. 3  shows the preferred embodiment installed on the ridgeline of a roof. 
     Alternate Embodiment 
     There are various possibilities with regard to the relative disposition of the essential components of this invention (flexible sealing main panel, fans, solar panel, and shroud).  FIG. 4  shows the ventilation apparatus according to an alternate embodiment of the invention. As shown, the apparatus includes a rectangular panel, the main panel, ( 21 ) with a laterally flexible section allowing the panel to be installed over, to cover and seal the apex of a roof in which the upper section of the decking has been removed to allow air flow through the ridge. The laterally flexible panel is sealed along its edges to promote airflow through the active portion of the device ( 131 ). Holes are cut in to the laterally flexible panels central section to allow for the installation of a series of axial fans ( 51 ) enabling them to extract air ( 111 , 61 ) from beneath the panel and exhaust it into the panels upper cavity formed by a flexible shroud ( 41 ) which surrounds a solar panel. The fans are held in position on the main panel by standard fasteners. The flexible shroud ( 41 ) extends from the main panel to the periphery of a solar panel ( 141 ). The solar panel is attached to the main panel by rigid members ( 161 ) with flexible joints to allow for installation over the ridge of a roofline. The rigid members support the solar panel and suspend it above the main panel. Together with the flexible shroud, the solar panel form a cavity above the flexible main panel in which the hot exhaust air flows ( 111 ). The shroud and solar panel serve to protect the fans from precipitation and debris. The shroud ( 41 ) itself is also flexible allowing it to flex with the main panel ( 21 ) during installation. The wiring for powering the fans, routed from an electrical box beneath the solar panel ( 151 ), runs to a thermostat contained within the cavity and then runs to the fans within the cavity formed by the flexible shroud and solar panel above the main panel ( 81 ). The thermostat prevents power flow to the axial fans at cooler ambient temperatures. The flexible shroud that along with the solar panel forms the air collection cavity above the main panel is fastened to the main panel and solar panel by standard fasteners ( 31 ). The flexible shroud has holes ( 71 ) cut into it. The holes are covered with a fine mesh screen to preclude the entrance of debris. The holes permit the air removed from the attic to be flowed to the ambient environment. For installation, the main panel is fastened over the roof ridge using standard fasteners ( 121 ). The main panel is fastened to the roof top decking over the existing shingle ( 11 ) which are held in place by decking fastened to the rafters ( 91 ). The axial fans are suspended over the ridge&#39;s ridge beam ( 101 ) (if present) in the ridge opening allowing air to flow from the attic space through the ridge opening, through the fan and into the collection cavity over the main panel and subsequently out through the mesh covered vents to the ambient environment.  FIG. 6  shows an alternate embodiment installed on the ridgeline of a roof. 
     The preferred and alternate embodiments uniquely incorporate a main panel for roofline sealing, axial fans, a shroud forming a secondary cavity and power source into a single device that can be installed at the exterior ridge of a home. As a result, the preferred embodiment and alternate embodiment solve many of the problems associated with prior forms of attic ventilation, including installation difficulty, aesthetics, roof compatibility, efficiency, debris and cost. 
     Installing the apparatus as one piece and installing the apparatus on the exterior simplify the installation process by minimizing work needed to be performed to fasten the device to the roof and allows the user to avoid reach, heat, and interference concerns associated with working from within the attic space. Installation from the exterior of the rooftop or attic also requires no modifications to the internal structural members of the attic space. In many instances it is expected that the preferred embodiment and alternate embodiment will be installed on roofs with existing passive ridge vents. This will allow homeowners to take advantage of existing ridge passthrough and thus eliminating the need, work and risks associated with cutting a hole in the roof decking. The preferred and alternate embodiments do not require an external electrical power source. This eliminates the need of an electrician or other electrical expert during the installation. 
     The preferred embodiment and the alternate embodiment are designed to be incorporated with an existing roof ridge vent or to mimic the look of a passive roof ridge vent. The key to this feature is placing the axial fans at the main panel&#39;s apex beneath a shroud that mimics the appearance of the existing ridge roofline and minimizes the disruption to the roof profile. This maintains a low profile stance, which makes the device as installed aesthetically pleasing. 
     As mentioned, unlike many prior forms of attic ventilation, the preferred and alternate embodiments are installed entirely on the exterior of the roofline. This feature not only enables ease of installation but is also makes the device compatible with roofs utilizing a ridge beam or ridge board. This will make the preferred and alternate embodiments useful to a larger percentage of homeowners when compared to prior art. 
     The use of a shroud to create a secondary cavity above the main panel at the panel&#39;s apex has advantages in that it allows the use of axial fans which can be larger and more efficient than would be permissible if fans or other devices were placed at a passive ridge vent outlets (as is done in some prior art). The efficiency enabled by the use of axial fans mounted at the main panel&#39;s apex is an import quality of the preferred embodiment and alternate embodiment. They reduce the power needed to obtain an adequate airflow through device. Additionally, power requirements of the described embodiments is reduced by not needing or using a sophisticated controller. The device&#39;s operation is directly moderated by the intensity of the sun. Minimizing the power needed for adequate airflow is important especially for solar powered applications. Power requirements drive the size of solar panel needed to operate the powered vent. As the preferred and alternate embodiments, contain all of the essential elements of a ventilation system minimizing size of the onboard solar panels is important. Additionally, the solar panel itself is the most costly feature of the device and minimizing its size/power output requirements reduces its cost. Component cost reductions make the described embodiments less expensive which intern makes the devices more attractive to the consumer. 
     For the preferred embodiment, placing the fans at the apex also allows enables use of a shroud that can protect the fans from debris and the natural environment by forming a secondary cavity. For the alternate embodiment, having the fans at a central location enables the single shroud/solar panel assembly to cooperate in protecting the fan or fans from the elements. Completely enclosing the active devices prevents debris from prohibiting fan operation, an advantage that the embodiments described have over some prior art. 
     Although the description above contains much specificity, these should not be construed to as limiting the scope of the embodiments but as merely providing illustration of some of the presently preferred embodiments. Thus the scope of the embodiments should be determined by the appended claims ant their legal equivalent, rather than by examples given.