Sealable curtain

A rollup closure utilizes a flexible cover or curtain selected from a material suitable to effect the type closure sought such as against light, ventilation, noise, sound or moisture. The cover is at least as wide as the opening to be covered and is longer than the opening is high. Each lateral margin of the cover has a strip of closure material affixed thereto, and a complimentary strip is affixed to the inside of a channel member. The top of the curtain is rigidly affixed across the top of the opening. The bottom of the curtain is upturned and connected to a driven take up roller mounted atop the opening. An elongated rod is supported within the upturned end of the curtain with its ends captured within the channels on each side of the opening. A weighting rod is supported atop the elongated rod and separated therefrom by the upturned end of the curtain, with the ends of the weighting rod also captured in the lateral channels. Activation of the driven roller lengthens or shortens the effective length of the curtain and moves the rods upwardly within the channels such that the mating closures are positioned to seal and unseal the curtain to the channel. Alternative embodiments may have multiple layers of curtain material or various sealing arrangements incorporated.

FIELD OF THE INVENTION 
The present invention relates to the field of closures for windows, doors, 
or portals and more particularly to closures which can be selectively 
positioned. In greater particularity the present invention relates to a 
non-sliding roll up closure for a portal. 
BACKGROUND 
Various applications are known wherein a portal requires a cover to prevent 
the passage of wind, rain, light, or anything else through the portal. As 
used herein portal simply means an opening which would allow the passage 
of such therethrough, hence a portal may be a window which is transparent 
to light and the cover of the instant in invention may control the passage 
of any of the above therethrough. Primarily, the genesis of the present 
invention resides in the need for large covers for large portals such as 
may be found on patios, pool houses, green houses, livestock houses, 
atriums or any other similar structure. The portal may be as small as 
would accommodate a ventilation fan in a gymnasium or livestock house or 
as large as an atrium wall in a solar efficient building. The cover may 
also be used for an inclined roof panel. 
SUMMARY OF THE INVENTION 
It is the principal object of the present invention to provide a means for 
effectively sealing large openings such as windows and doors in a number 
of differing types of buildings. 
Another object of the invention is to provide a reliable and easily 
operated closure for such portals. 
Still another object of the invention is to provide a closure which is 
relatively impervious to the accumulation of debris thereon. 
These and other objects and advantages of our new closure are accomplished 
through the use of a novel combination of features in a roll up closure. 
The present closure utilizes a flexible cover or curtain selected from a 
material suitable to effect the type of closure sought. For example, if 
the closure is to allow ventilation, but obstruct light, the material of 
the curtain would be of a weave that would be permeable to air, but block 
a certain amount of light. Similarly, the closure could be pervious to 
moisture yet permeable to air, or vapor proof yet transparent, or opaque 
and vapor proof as the needs of the building on which the closure is used 
require. The cover is at least as wide as the opening to be covered and is 
longer than the opening is high. Each lateral margin of the cover has a 
strip of hook and pile fastener material affixed thereto, and a 
complimentary strip is affixed to the inside of a channel member. The top 
of the curtain is rigidly affixed across the top of the opening. The 
bottom of the curtain is upturned and connected to a driven take up roller 
mounted atop the opening. An elongated rod is supported within the 
upturned end of the curtain with it's end captured within the channels on 
each side of the opening. A weighting rod is supported atop the elongated 
rod and separated therefrom by the upturned end of the curtain, with the 
ends of the weighting rod also captured in the lateral channels. 
Activation of the driven roller lengthens or shortens the effective length 
of the curtain and moves the rods upwardly within the channels such that 
the mating hook and pile fasteners are positioned to seal and unseal the 
curtain to the channel. Alternative embodiments may have multiple layers 
of curtain material or various sealing means incorporated.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
Referring to the Drawings for a clearer understanding of the invention, it 
will be appreciated that our apparatus is usable with a variety of 
building types, and is usable to cover a variety of openings such as 
doors, sidewalks, roofs, windows, and skylights in such applications. 
Accordingly, the following description is intended to encompass any 
specific use to which the structure may be afforded. Referring to FIGS. 1 
& 2, it may be seen that the opening 11 to be covered is provided with a 
pair of inwardly facing channel members 12 and 13, being C-shaped in the 
horizontal plane. Channel members 12 and 13 extend the full vertical 
length of the opening 11 and may terminate at a lower channel 14, which is 
upwardly opening and which extends across the width of the opening. In 
some applications a sealing gasket 16, such as a compressible layer of a 
foam like material will be useful in the bottom of lower channel 14. 
Across the top of opening 11 is a brace 17 which extends from channel 12 
to channel 13. Thus, it may be seen that the opening is completely framed 
by members 12, 13, 14, and 17. 
Attached to brace 17 is a first end of a curtain 18, which is a flexible 
material selected in accordance with the purposes of the present invention 
for its ability to block or transmit light, air, or moisture from one side 
to the other thereof. As an air barrier, we have noted that a woven 
polyester fabric has exhibited good durability having withstood over 
60,000 cycles of operation of the invention. However, canvas, other 
plastics, some metals and fabrics which are selectively permeable are 
known to exist which may find application in the present invention. 
Therefore, curtain 18 is properly defined as a flexible barrier material, 
having a first end 19 secured to brace 17 and opposing longitudinal sides 
21 and 22 which are longer than the length of channel members 12 and 13 
such that the curtain 18 has an upturned lower end 23. Attached to 
channels 12 and 13 and to sides 21 and 22 are complementary closure 
members 26 and 27. For example, hook and loop fastener material was 
attached to the polyester fabric used in testing the invention and to the 
inside of channels 12 and 13 such that the sides 21 and 22 could be 
selectively attached and detached from the channels. Other means of 
fastening, such as magnetic strips may be used when appropriate to the 
particular application. Note that the closure members need only be 
commensurate in length with the length of the channels, thus the upturned 
end 23 of curtain 18 does not need the fastener material. A transverse 
closure may be provided in conjunction with lower channel 14; however, on 
a door, channel 14 would not be present. 
The upturned end 23 may be directly connected to a transverse take-up 
spindle 31 mounted for rotation above the tops of channels 12 and 13. 
Alternatively, end 23 may be connected to the spindle 31 by cables 32 or 
straps, and the spindle may include a spool for such cables or straps. In 
any case, the spindle 31 is driven by a reversible motor 33 attached to a 
selected means of control and supports the upturned end 23. An elongated 
roller 34, which may be a solid or tubular pipe, is supported within the 
curve of the curtain 18 created by the upturned end 23 and has opposing 
ends which extend into the opposing channels 12 and 13 such that roller 34 
can roll freely vertically in the channels, but cannot pivot in the 
horizontal plane about its mid point, thus as spindle 31 is rotated to 
wrap lower end 23 thereon roller 34 is lifted within channel 12 and 13 
such that it rolls up the channel. A weighting roller 35 is captured at 
opposing ends within the channels 12 and 13 parallel to elongated roller 
34. Weighting roller 35 is captured by the channels above roller 34 and is 
separated from roller 34 by the upturned end of curtain 18. Thus, as 
splindle 31 rotates rollers 34 and 35 are constrained to rotate in 
opposite direction with the upturned end of flexible curtain 18 passing 
between the rollers. As splindle 31 unwraps the curtain or straps from 
itself, gravity urges the rollers and curtain to a lowered position. 
It will be appreciated that channels 12 and 13 are wider than the diameter 
of rollers 34 and 35 such that roller 35 is supported in offset vertical 
relation to roller 34, therefore, a lateral component of the weight of the 
rollers is applied to the channel members. Accordingly, the sides of the 
curtain 21 and 22 carrying the closure 27 are pressed by this component of 
force against the complimentary closure 26 of the channel, thereby 
ensuring a sealing connection. It will be appreciated that the downward 
force of gravity due to the weight of the roller and the lateral force 
component generated by the offset position of the rollers keeps the 
curtain fabric taut at all times such that the sealing members are 
properly engaged, thus insuring proper tensioning of the curtain. As 
spindle 31 raises the end of the curtain and the rollers, the lifting 
force is transferred around roller 34 to provide an opening force to the 
closures nearly normal thereto, such that they are readily detached. From 
the forgoing it is easily seen that as spindle 31 rotates, it effectively 
varies the length of the curtain 18 such that rollers 34 and 35 urge the 
closure member into sealing the engagement above themselves. 
In an alternative embodiment shown in FIG. 5, a second curtain 41 is 
provided and is attached to a second brace 42. Second curtain 41 has the 
same structure as curtain 18 and has an upturned end 43 which passes 
beneath roller 35, but not roller 34. Upturned ends 43 and 23 are attached 
such that they are commonly supported by splindle 31, and move 
concomitantly vertically between braces 14 and 42. It will be appreciated 
that the closure members 46 carried by curtain 41 mate with closure 
members 47 mounted on the channels 12 and 13 to provide a double sealed 
barrier. 
The control mechanism may be any of a number of mechanisms depending on the 
needs of the application of the invention. For example, in a livestock 
confinement house where temperature control is a necessity, the present 
invention may be used as a cover for a ventilation fan, and as a variable 
height curtain over a window. In this situation a temperature controller 
such as the type manufactured by the assignee of this application may be 
attached to each motor for each curtain and constantly monitor the 
temperature in the house. In this manner, the fans may be uncovered and 
actuated, and the curtain raised or lowered to meet specific airflow 
conditions. In another example, the present invention may be used in a 
greenhouse, having a need to control the amount of sunlight on certain 
plants during particular months. In this situation, the motor may be 
controlled by a timer or may be connected to a sensing system connected to 
a plurality of photocells that incrementally indicate to the motor how 
much of the curtain should be raised or lowered. Likewise, the opening can 
be monitored to close during a rain shower. In the simplest case a switch 
to turn the motor on and off may be provided. Furthermore, limit switches 
of various kinds may be placed at various locations to further control the 
movement of the curtain, such that it may eliminate air curtains or the 
like. 
It is ostensibly noteworthy to mention that the present invention is not 
susceptible to sliding friction between pans all of mating surfaces 
contacting each other with a rolling relationship. Therefore, wear on the 
curtain is minimized, and the drive units do not have to overcome friction 
to position the curtain. Furthermore, the curtain is not susceptible to 
jamming due to debris being wedged into sliding engagement with a 
component since no sliding movement is provided. Accordingly, we have 
developed a rollup curtain system that is amenable to a variety of uses in 
numerous applications from residential to commercial to botanical to 
agricultural. 
While I have shown my invention in various forms, it will be obvious to 
those skilled in the art that it is not so limited, but is susceptible of 
various changes and modifications without departing from the spirit 
thereof.