BACKGROUND
Prior Art
This invention is an affordable method to vent greenhouses or other building roofs, using common relatively low cost available inputs. The flexible “umbrella vent” is durable in wind and rain whether closed or fully open. In the closed position, the vent is locked down by tensioned tether ropes secure from wind and rain. In the vertical fully open position, the “umbrella vent” system flexes in the wind supported by flexible tension hoops. When in the open position, the plastic folds approximately in half. This utility design is different from prior roof vent systems that primarily use costly rigid windows and rack and pinion mechanisms and are vulnerable to wind in the open positions as well as multiple sealing issues.
The “umbrella vent” technology is based upon principles of tension and support to create a functional method to employ the use of lower cost flexible plastic sheeting in a controlled system to vent greenhouse or other building's air. The flexible “umbrella vent” system eliminates multiple fragmented openings of prior venting applications by the continuous uninterrupted use of a single sheet of flexible plastic or materials that are moveable and controlled while opening to vent air.
DETAILED DESCRIPTION
Preferred Embodiment
This invention design provides up to a four foot opening for ventilation of a greenhouse roof vent that is covered with flexible plastic sheeting. The retractable umbrella greenhouse vent is mounted between two horizontal 2″×4″ treated wood members which can also be steel or aluminum (FIG. 2). The horizontal members are clamped or screwed onto a greenhouse or building frame, the highest member 2″×4″ being at or near the peak and the lower member 2″×4″ placed 4 feet lower down the slope of the greenhouse roof. Wire hoops acting as support and torsion are inserted into the lower horizontal member of the vent frame by drilling a small hole to receive the 76″× 3/16″ wire torsion hoops (FIG. 4). The hoop holes are above the poly-lock extrusion mounted on the same lower vent member. The hoops are placed one after another, spanning one greenhouse or building rafter or bow to the next to form a wall of torsion hoops that run the length of a greenhouse or building (FIG. 7). Flexible woven or conventional plastic sheeting or another flexible material is attached to the lower member of the vent just behind the wall of hoops (FIG. 5). The flexible plastic sheeting is pulled up and over the wall of hoops which tensions the plastic (FIG. 5), advancing to a pull pipe and is attached to the pull pipe with screwed on compression clamps (FIG. 8). The pull pipe tows the plastic toward the peak via tether ropes. The ⅛″ or 3/16″ polyester braided ropes are connected to the pull pipe by passing through drilled holes and, are knotted or by clamping onto the pull pipe (FIG. 9). The pull pipe is standard galvanized 1.315 greenhouse rollup curtain pipe or other pipe or tube. The hoop torsion system is different from any other plastic system because it simultaneously retracts and tensions free plastic or flexible sheeting in a venting process (FIG. 5). The plastic or flexible sheeting for the vent requires an additional width of about 1 foot more or less to allow the tensioning function to work properly. For example, approximately 5 feet of flexible material is needed for a 4 foot opening. This slack provides free play so that when the tethered pull pipe is winched to close the vent, the torsion hoops are slightly flexed from the near vertical position toward the inclining slope of the greenhouse or other building rafters or bows (FIG. 5). This creates the umbrella effect which will shed rain and protect against wind forces. When the vent is closed the plastic or flexible material is fully tensioned. As the tethers are released from the lock down winch to open the vent, the torsion hoops retract to near vertical again retracting the pull pipe and flexible material to an opening of a foot or more. In a 96 foot greenhouse or other building, 12 rope tethers spaced 8 feet apart provide uniform pulling closing functions. The rope tethers are passed through the pipe and knotted or clamped so that the pipe and flexible material in tow can be pulled to the peak board (FIG. 6). The tether ropes continue to 9/32″ drilled holes in the peak board edge. The peak board holes are drilled through the peak board edge mid point at an angle toward vertical mounted pulleys which are screwed to the underside upper elevation of the peak board. This allows the pull pipe to close to the peak board edge unobstructed, taking care to align tether rope with pulley.
The tether ropes continue from the pull pipe passing through the peak board to the vertical mount pulleys which are mounted to the underside of the 2″×4″ peak board member, traversing through the pulley and advancing to mounted crank winches at lower greenhouse or building frame. The tether ropes turn 180 degrees at the vertical pulley (FIG. 5) proceeding back under the vent to a horizontal crank winch device (FIG. 10). The crank pipe is horizontal and transverses the length of the greenhouse or building. The tether ropes being connected to the pipe and powered by a dual output stationary winch gear box (FIG. 11) to provide necessary torque to open or close the “umbrella vent”. When the gear box is turned by a cordless drill or a hand crank, tether ropes are pulled simultaneously (FIG. 11). The dual-output gear box mounts in the center of the greenhouse or building separating the crank pipe in two directions.
An additional compliment to the umbrella greenhouse or building vent system is the installation of an aluminum extrusion at the peak that combines a poly lock for the permanent stationary plastic or flexible material attachment of the opposing fixed roof while at the same time extending plating to function as a drip cap for the flexible vent (FIG. 6). This dual purpose aluminum extrusion includes a 3″ extension for the drip cap and a lockdown for the opposing permanent roof plastic or flexible material. The drip cap seals the peak board weather juncture from rain and ice. Closure at the gable ends of the greenhouse or building “umbrella vent” is accomplished by extending free plastic 4 foot and inserting 3 grommets which provide attachment points for 3 rope tethers joined to a steel ring attached to a light bungee cord to anchor at the end wall of the greenhouse or building to a steel eyebolt (FIG. 7). Flexing of the bungee allows the partial opening of the “umbrella vent”. To open the “umbrella vent” fully, the bungee is moved to a second eyebolt to relax the end wall tethers further (FIG. 7)
DRAWINGS
Figures
FIG. 1 shows a longitudinal piece of continuous flexible plastic sheeting or of other flexible poly-like materials. Extended flexible material projects beyond the roof ends turning to vertical sides at gable or bow ends. Grommets are attached and tether ropes are secured proceeding to a ring attached to a single bungee cord which anchors to an eye bolt lower down the end wall which functions to close the roof vent at the building ends.
FIG. 2 demonstrates flexible material attachment to galvanized pipe which serves in pulling or retracting the said material. The tether ropes are very low stretch polyester.
FIG. 3 exhibits the peak board member with a vertical mount pulley screwed to the underside of the board. FIG. 3a shows a drilled hole which tapers to the vertical pulley at a slight elevation under the peak board. Tether ropes of the vent system pass through the holes in the peak board edge to enjoin the pulleys.
FIG. 4 shows the torsion hoops that tension the flexible material.
FIG. 5 demonstrates the tension effect and convexity of the umbrella like vent, as the vent is cranked or pulled to close.
FIG. 6 demonstrates the unique drip cap sealing fixture which at the same time provides a clamp for flexible material from opposing roof.
FIG. 7 shows building vent with hoops installed.
FIG. 8 shows a compression clamp and a screwed on clamp.
FIG. 9 shows pull rope under compression clamp or alternate pull rope passing through pull pipe.
FIG. 10 shows horizontal pipe for crank with tethers.
FIG. 11 shows gear box and horizontal pipe with crank.
FIG. 12 shows building end view of flexible material in a convex profile as the vent is closed.
Patent Application
20110120029
