The subject disclosure relates generally to a horizontal side-rolling fabric door and more specifically to a bottom seal for such a door.
Basically, there are two types of fabric rollup doors, those that have a curtain that rolls up vertically and those that roll up sideways. For vertically operating rollup doors, a horizontal drum or roller above the doorway takes up or pays out a fabric curtain to respectively open or close the door. An example of a vertically operating rollup door is shown in U. S. Pat. No. 7,151,450.
Side-rolling or horizontal side-rolling fabric doors, such as the one disclosed in U.S. Pat. No. 4,096,902; includes one or two vertical rollers at either one or both lateral edges of the doorway. Some side-rolling doors have a single roller at one side of the doorway with a single curtain that extends and retracts across the full width of the doorway.
In some cases, the “single curtain” is actually comprised of two layers, each having its own vertical take-up roller. In such cases, the two rollers are right next to each other at one lateral edge of the doorway. As the door opens, the two layers of the curtain separate at the edge of the doorway and wrap upon their respective rollers.
Other side-rolling doors include two individual curtains, each supported by their own roller at opposite lateral edges of the doorway. For such doors, the two separate curtains meet at the center of the doorway as the door closes. To open the door, the two curtains move apart from each other and wrap upon their own roller (or set of rollers if each curtain has two layers).
Side-rolling doors, particularly those with two curtains, provide an almost instant field of view through the doorway as the door begins to open, whereas vertically operating doors generally need to open much farther in order for a person on one side of the doorway to see what is at the other side of the door. An instant field of view can provide an early warning of a potential collision at the doorway.
With side-rolling doors, however, it can be difficult to seal the lower edge of the curtain adjacent the floor. Since the lower edge of the curtain itself tends to wear prematurely due to repeated rubbing against the floor and, thus, eventually the entire curtain might need replacing to maintain an adequate seal.
FIG. 1 is a front view a horizontal side-rolling door shown in a closed position.
FIG. 2 is a front view of the door of FIG. 1 but showing the door open.
FIG. 3 is a closer view of the lower right corner of the door shown in FIG. 2.
FIG. 4 is a front view of another horizontal side-rolling door shown in a closed position.
FIG. 5 is a front view of the door of FIG. 4 but showing the door open.
Certain examples are shown in the above-identified figures and described in detail below. In describing these examples, like or identical reference numbers are used to identify common or similar elements. The figures are not necessarily to scale and certain features and certain views of the figures may be shown exaggerated in scale or in schematic for clarity and/or conciseness. Additionally, several examples have been described throughout this specification. Any features from any example may be included with, a replacement for, or otherwise combined with other features from other examples.
FIGS. 1-3 show a horizontal side-rolling door 10 with at least one curtain 12 that moves horizontally across a doorway 14 to open and close the door 10. In this particular example, door 10 includes two curtains 12 supported by spring-loaded rollers 16 installed in proximity with lateral edges 18 of doorway 14. A preloaded torsion spring 20 urges each roller 16 to rotate in a direction that tends to draw in and wrap the respective curtain 12 onto itself. An overhead track 22 and drive unit 24 coupled to the leading edges of curtains 16 are used for opening and closing the door 10. FIG. 1 shows door 10 closed with leading edges of curtains 12 abutting each other near the center of doorway 14, and FIGS. 2 and 3 show door 10 open with most of the curtains 12 wrapped around rollers 16.
To provide a means for replacing a worn bottom edge of curtain 12 and/or to seal a gap that might exist between curtain 12 and floor 26, each curtain 12 includes a replaceable bottom seal 28. Seal 28 is replaceable by virtue of a separable joint 30, such as, for example, a zipper, hook-and-loop connector, snaps, lace, or some other reconnectable means. As bottom seal 28 becomes worn, joint 30 allows seal 28 to be readily replaced without having to replace the entire curtain.
If a replaceable seal were simply added to the lower edge of an ordinary horizontal side-rolling door, the seal and/or the joint that connects the seal to the curtain would likely be thicker than the curtain material itself, and that could cause some problems. As the door opens and the curtain wraps around the roller, a relatively thick seal and joint could build up on the roller, which could create a substantial bulge at the lower end of the roller. The bulging area might press against the floor or other adjacent surfaces and interfere with the roller being able to smoothly take up the curtain. The bulging section might also twist and strain adjacent areas of the curtain.
To avoid such problems, even though joint 30 might be thicker than curtain 12, joint 30 preferably lies at an incline so that as curtain 12 wraps around roller 16, joint 30 is broadly distributed in an approximate helical pattern 32 as shown in FIG. 3. The terms, “incline” and “inclined” mean being angularly displaced relative to a horizontal plane. The incline or slope of joint 30 can be positive or negative, thus joint 30 could wrap helically upward or downward as the door opens.
The various components of door 10 may vary. Curtain 12, for instance, can be comprised of a pliable sheet, fabric, or any continuous or segmented panel with sufficient flexibility to wrap around roller 16. Referring to FIG. 3, each roller 16 can be comprised of a rotatable outer drum 34 journaled about a stationary central shaft 36. Opposite ends of spring 20 (FIG. 1) are connected to drum 34 and shaft 36 so that preloaded spring 20 urges drum 34 to rotate about shaft 36, thereby pulling curtain 12 taut and providing impetus for curtain 12 to wrap around roller 16.
Drive unit 24 can be comprised of a chain 38 or cogged belt driven between a motor-driven sprocket 40 and an idler sprocket 42 or may comprise any other suitable components. Track followers 44 and 46, rolling or sliding along track 22, couple the leading edges of curtains 12 to chain 38. Track follower 44 connects one curtain 12 to an upper part of chain 38, and track follower 46 connects the other curtain 12 to the lower section of chain 38 so that drive unit 24 can move track followers 44 and 46 and their respective curtains 12 in opposite directions to selectively open or close the door.
To simplify manufacturing, seal 28 can be made as part of a generally rectangular seal assembly 48, wherein the assembly comprises an upper piece 50 and bottom seal 28. Assembly 48 can be sewn, bonded, welded or otherwise attached to create a generally horizontal seam 52 that connects assembly 48 to a lower portion of curtain 12. Once connected by seam 52, upper piece 50 of seal assembly 48 now becomes an extension of curtain 12 itself, in which case an inclined lower edge 54 of curtain 12 is where bottom seal 28 is removably connected via separable joint 30. Since seam 52 is generally horizontal and joint 30 is inclined, seam 52 and joint 30 are displaced out of co-parallel alignment with each other. Lower edge 54 can be any edge near the bottom of curtain 12 and is not necessarily the lowermost edge of the curtain. Seam 52 preferably, but not necessarily, provides a more permanent connection than does separable joint 30.
Although bottom seal 28 can be any lower piece or segment in proximity with floor 26, seal 28 does not necessarily have to be touching floor 26 in order to be considered a bottom seal. Nonetheless, bottom seal 28 preferably engages floor 26. To ensure such engagement, bottom seal 28 can be comprised of a loop 56 (FIG. 3) of flexible material with a flexible but somewhat stiffer or heavier elongate insert 58. The weight and/or relative stiffness of insert 58 helps hold loop 56 of seal 28 down against floor 26.
Loop 56 and insert 58 can add bulk and thickness to bottom seal 28. To prevent such thickness from creating a bulge at the lower end of roller 16 as door 10 opens, seal 28 preferably extends below a major outer periphery 60 of drum 34, as shown in FIG. 3. This allows loop 56 and insert 58, if the curtain includes such a loop and insert, to coil about itself in a more open area 62 that is underneath the larger diameter part of drum 34. The bottom end of drum 34 could be even higher to allow additional room for the coiling of a horizontal or inclined joint 30 in the same way, or the drum could have multiple stepped diameters to accommodate a curtain having multiple areas of different thickness. The expression, “major outer periphery” of a roller refers to the maximum outer surface about which the curtain is wrapped. In the case of a cylindrical roller (as opposed to an octagonal or multifaceted one), the major outer periphery is the roller's maximum outer diameter.
Although seal assembly 48 might simplify manufacturing, FIGS. 4 and 5 show a horizontal side-rolling door 10′ where bottom seal 28 is attached directly to a curtain 12′ without using upper piece 50 and seam 30. Other than the omission of upper piece 50 and seam 30, door 10′ is structurally and functionally the same as door 10, with FIGS. 4 and 5 corresponding to FIGS. 1 and 2 respectively. Reference numbers in FIGS. 4 and 5 that are the same as those used in FIGS. 1 and 2 correspond to structures that are similar or identical to those described in connection with FIGS. 2 and 3.
At least some of the aforementioned examples include one or more features and/or benefits including, but not limited to, the following:
In some examples, a horizontal side-rolling door includes a replaceable bottom seal.
In some examples, a horizontal side-rolling door includes an inclined disconnectable joint that connects a bottom seal to the door's curtain.
In some examples, a horizontal side-rolling door includes an inclined zipperjoint that connects a bottom seal to the door's curtain.
In some examples, a horizontal side-rolling door includes a roller with extra space below the roller to provide roll-up room for a relatively thick bottom seal.
In some examples, a horizontal side-rolling door includes a roller with extra space below the roller to provide roll-up room for a bottom seal that comprises a loop of material containing a weighted and/or stiffening element.
In some examples, a horizontal side-rolling door includes a disconnectable joint that connects a bottom seal to the door's curtain, wherein the joint wraps upon a roller in an approximate helical pattern.
In some examples curtains 12 could be comprised of a series of rigid vertical slats that are pivotally interconnected side-by-side, thereby providing a flexible curtain assembly. Such an assembled curtain could coil about relatively short upper and lower rollers rather than wrapping around one long continuous roller.
Furthermore, although certain example methods, apparatus and articles of manufacture have been described herein, the scope of coverage of this patent is not limited thereto. On the contrary, this patent covers all methods, apparatus and articles of manufacture fairly falling within the scope of the appended claims either literally or under the doctrine of equivalents.