Patent Description:
Cold storage rooms are refrigerated areas in a building that are commonly used for storing perishable foods. Cold storage rooms are typically large enough for forklifts and other material handling equipment to enter. Access to the room is often through a power actuated insulated door that separates the room from the rest of the building. To minimize thermal losses when someone enters or leaves the room, the door preferably opens and closes as quickly as possible.

Vertically operating roll-up doors and similar doors with flexible curtains are perhaps some of the fastest operating doors available. When such a door opens, its curtain usually bends upon traveling from its closed position in front of the doorway to its open position on an overhead storage track or take-up roller.

Such bending is not a problem if the curtain is relatively thin. However, an insulated curtain may not bend as well due to the required thickness of the insulation. When a take-up roller or curved track bends a thick curtain, relative translation may occur between opposite faces of the curtain. Designing a thick, insulated curtain that can accommodate such translation can be challenging. <CIT> discloses a flexible door panel according to the preamble of independent claim <NUM>. <CIT> discloses a barrier comprising a layer of weft knitted texturized glass fabric. Further, a heat reflective layer such as an aluminium foil is located adjacent each surface of the fabric. Each aluminium layer is bonded to an outer layer of woven glass fabric. The outermost surface of each fabric layer is coated with a thin skin of silicone rubber to provide abrasion resistance.

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 the same 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.

<FIG> illustrate an example of a vertically operating door <NUM> not part of the invention, that includes a flexible, insulated door panel <NUM>. Door <NUM> is shown closed in <FIG>, partially open in <FIG>, and fully open in <FIG> and <FIG>. In the illustrated example, as door <NUM> opens and closes relative to a doorway <NUM>, door panel <NUM> bends over a mandrel <NUM>. Mandrel <NUM>, in some examples, is a fixed bar or a roller extending across the width of doorway <NUM>. Although door panel <NUM> is shown having a certain double-bend, stored configuration, other stored configurations, such as coiled, wound on a roll tube, single-bend horizontal, serpentine, vertically planar, etc., are all well within the scope of this disclosure.

Although door <NUM> is useful in unlimited applications, door <NUM> is particularly suited for providing access to refrigerated cold storage rooms or for separating rooms or areas that are at different temperatures, such as, for example, the interior and exterior of a building at a truck loading dock. In such temperature differential installations, one side of door panel <NUM> is often colder than the other side, which can subject door panel <NUM> to an adverse water vapor pressure gradient. While <FIG> disclose general features of example door panel <NUM>, <FIG> and <FIG> disclose more detailed features specifically intended to address the problems associated with the water vapor pressure gradient.

To operate door <NUM>, in some examples, a powered drive sprocket <NUM> (<FIG>) engages a cogged strip <NUM> at each lateral edge of door panel <NUM> to move door panel <NUM> between a lower guide track <NUM>, where door panel <NUM> is blocking doorway <NUM>, and an upper track <NUM> where door panel <NUM> is clear of the doorway <NUM>. It should be noted, however, that door panel <NUM> can be applied to various other types of doors that operate with different drive or storage configurations.

In some examples, door panel <NUM> includes a plurality of pliable baffles <NUM> (<FIG>, <FIG> and <FIG>) that restrict the redistribution of air contained between a first sheet <NUM> and a second sheet <NUM> of door panel <NUM>. Sheets <NUM> and <NUM> are joined and generally sealed along their outer perimeter to create one large overall air chamber <NUM> between sheets <NUM> and <NUM>. Baffles <NUM> divide chamber <NUM> into a plurality of more manageable smaller chambers <NUM>. For illustrative clarity, baffles <NUM> and chambers <NUM> and <NUM> are shown in <FIG> to extend slightly less than a full width <NUM> of door panel <NUM>, however, baffles <NUM> and chambers <NUM> and <NUM> preferably extend the full width of door panel <NUM>. As door <NUM> opens and creates a horizontal crease in sheets <NUM> and <NUM> (e.g., where door panel <NUM> bends over mandrel <NUM>), baffles <NUM> help prevent air trapped within chamber <NUM> from over inflating the lower end of door panel <NUM>. Thus, baffles <NUM> prevent the area between mandrel <NUM> and a lower leading edge <NUM> of door panel <NUM> from bulging excessively as door <NUM> opens.

In some examples, baffles <NUM> are sufficiently flexible to accommodate some relative translation between sheets <NUM> and <NUM> as door panel <NUM> bends over mandrel <NUM>. The flexibility of baffles <NUM> may also enable door panel <NUM> to restorably break away if something were to accidentally collide with the door <NUM>. Additionally or alternatively, some examples of baffles <NUM> are sufficiently flexible to conformingly mate with the lateral edges or vertical seams <NUM> of sheets <NUM> and <NUM> so that there is minimal leakage or air exchange between chambers <NUM>. Further, in some examples, baffles <NUM> are sufficiently stiff to maintain a desired spacing between sheets <NUM> and <NUM>, particularly in examples where insulation is not used for maintaining such spacing. Further yet, in some examples, baffles <NUM> have a thermal resistance (i.e., R-value) that is equal to or greater than that of sheets <NUM> and <NUM>.

Although the actual construction of door panel <NUM> may vary, the illustrated examples have sheets <NUM> and <NUM> being made of any suitable polymeric or natural fabric material that is preferably pliable and can be joined along their outer perimeter by adhesion, tape, melting/fusing/welding, sewing, hook-and-loop fastener, snaps, rivets, zipper, etc. The term, "polymeric," as used in this patent to describe a material means that the material includes at least some plastic or polymer base, substrate or coating. The term, "pliable" as used in this patent to describe a sheet of material means the sheet is sufficiently flexible to be folded over onto itself and subsequently unfolded without appreciable permanent damage. For toughness, wear resistance, heat seal weldability and flexibility, some examples of sheets <NUM> and <NUM> comprises polyurethane sheet material between about <NUM> and <NUM> thick (thickness <NUM>). In some examples, substantially the entire outer perimeter, including seams <NUM> and the upper and lower edges of door panel <NUM>, is sealed to prevent appreciable amounts of air from flowing in and out of chamber <NUM>. Inhibiting moist air from repeatedly entering chamber <NUM> can prevent mold-promoting water vapor from condensing inside chamber <NUM> on a panel sheet that is facing, for example, a cold storage room.

Baffles <NUM> can be made of a material similar to or different than that of sheets <NUM> and <NUM>. The flexibility of sheets <NUM> and <NUM> enables door panel <NUM> to bend over mandrel <NUM>, while the flexibility of baffles <NUM> enables limited relative translation between sheets <NUM> and <NUM> as door <NUM> opens and closes. As door <NUM> opens or closes and door panel <NUM> travels and bends across mandrel <NUM>, this action urges relative vertical translation between sheets <NUM> and <NUM>. In some examples, thermally insulating pads <NUM> (e.g., resiliently compressible foam pads, polyester batting, etc.) are installed within chambers <NUM>. The term, "thermally insulating," as used in this patent to describe pads <NUM> within door panel <NUM> means that the pads provide the greatest contribution of the door panel's overall thermal resistance or R-value.

For the illustrated examples, baffles <NUM> are horizontally elongate, which enable the baffles <NUM> to not only restrict vertical airflow within door panel <NUM> but also to accommodate relative vertical translation between sheets <NUM> and <NUM>. In other examples, door panel <NUM> is provided with vertically elongate baffles or a combination of vertical and horizontal baffles.

To effectively restrict airflow within door panel <NUM>, horizontally elongate baffles <NUM> preferably extend along at least most of the full width <NUM> of door panel <NUM>. To facilitate manufacturing, however, baffles <NUM> can be made slightly shorter than the panel's full width <NUM> to make it easier to join the lateral vertical edges of sheets <NUM> and <NUM> together. Baffles <NUM> being a little shorter than full width <NUM> of door panel <NUM> places the plurality of air chambers <NUM> in fluid communication with each other. Thus, as door <NUM> opens and door panel <NUM> travels across mandrel <NUM>, some air within door panel <NUM> will be temporarily redistributed to at least one of the lower chambers (e.g., air chamber <NUM>') of the plurality of chambers <NUM>, thereby slightly increasing the air pressure within chamber <NUM>' temporarily, but not really detrimentally.

Although the general assembly of door panel <NUM> can be accomplished by various means, <FIG> illustrates one example manufacturing method. One horizontal edge of each baffle <NUM> is melted or ultrasonically welded to first sheet <NUM>, thereby creating a plurality of fused joints <NUM> between sheet <NUM> and each of baffles <NUM>. Fusing baffles <NUM> to at least one of sheets <NUM> and <NUM> is schematically depicted by the block at reference number <NUM> of <FIG>. Alternate methods of attaching baffles <NUM> in place include, but are not limited to, bonding, taping, sewing, fastening via hook-and-loop fastener, riveting, etc..

An outer perimeter of sheet <NUM> is fused, sewn or otherwise connected to sheet <NUM> as schematically depicted by the block at reference number <NUM> of <FIG>. The plurality of baffles <NUM> are installed between sheets <NUM> and <NUM>, as schematically depicted by arrow <NUM> and insulation pad <NUM> is installed within chambers <NUM>, as schematically depicted by arrows <NUM>. The example method represented by the block at reference number <NUM> and arrows <NUM> and <NUM> may be done generally together in a progressive sequence from one end of door panel <NUM> to another or in any other suitable order. <FIG>, for example, shows door panel <NUM> being assembled progressively from the bottom up.

Sheets <NUM> and <NUM>, when made of polyurethane, have significant resistance to water vapor transmission therethrough. Nonetheless, some water vapor might still permeate the warmer of sheets <NUM> and <NUM> and migrate through pads <NUM> toward the colder sheet <NUM> or <NUM>. If sheet <NUM>, for example, is warmer than sheet <NUM>, water vapor might permeate door panel <NUM> through sheet <NUM> and condense and perhaps freeze on the inner surface of sheet <NUM>. An accumulation of trapped liquid water or ice within chamber <NUM> may inhibit normal operating characteristics of the door panel <NUM>.

To address this potential problem, thermally insulating pads <NUM>, as shown in the example of <FIG>, is substantially encircled and/or surrounded and preferably encased by a sheet <NUM> (third sheet) that has a lower water vapor transmission rate than that of polyurethane. In some examples, sheet <NUM> starts as a tube in which pad <NUM> is inserted. After pad insertion, the axial ends of the sheet's tubular form are, in some examples, heat sealed to totally encase pad <NUM> within sheet <NUM>, somewhat analogous to a bed pillow in a pillow case. Examples of sheet <NUM> include, but are not limited to, polyester, polyethylene and aluminum foil. In some examples, sheet <NUM> is between about <NUM> and <NUM> thick (thickness <NUM>) with an R-value that is less than that of sheets <NUM> and <NUM>. Sheet <NUM> being much thinner than sheets <NUM> and <NUM> maximizes the insulating pad's thickness and thus the pad's R-value for a given door panel thickness. Having sheet <NUM> be relatively thin is a viable option because sheet <NUM> is protected by the tough outer sheets <NUM> and <NUM>. While the above example describes the sheet <NUM> surrounding the pad <NUM>, in other examples, the sheet or sheets <NUM> may be positioned adjacent one or more surfaces and/or faces of the pad <NUM>. For example, the sheet <NUM> may be positioned adjacent a face of the pad <NUM> between pad <NUM> and the sheet <NUM> (e.g., the sheet to be adjacent a warmer side of the building) while not being adjacent the other faces of the pad <NUM>. In other examples, the sheets <NUM> may be positioned adjacent opposing surfaces of the pad <NUM>, one of which being positioned between the surface <NUM> and the pad <NUM> and the other of which being positioned between the surface <NUM> and the pad <NUM>.

In addition or alternatively, in some examples, baffles <NUM> lean downward toward the warmer sheet, e.g., toward sheet <NUM>. In the illustrated example, the baffles <NUM> are at a non-perpendicular angle relative to a longitudinal axis of the panel <NUM> such that ends of the baffles <NUM> are longitudinally displaced along the longitudinal axis of the panel <NUM>. This allows baffles <NUM> to drain any accumulated liquid water within chamber <NUM> down through optional condensate drain holes <NUM> in sheet <NUM>. Baffle <NUM> being inclined also allows adjacent pads <NUM> to overlap at the pads' upper and lower edges, thereby ensuring vertically overlapping insulation at baffles <NUM>. A baffle <NUM>' is an alternate example configuration of baffle <NUM>.

In addition or alternatively, as shown in <FIG>, a sheet <NUM> (another example third sheet) having a lower water vapor transmission rate than that of polyurethane is installed between pad <NUM> and sheet <NUM> to block water vapor on the exterior side of sheet <NUM> from penetrating chamber <NUM>. Examples of sheet <NUM> include, but are not limited to, polyester, polyethylene and aluminum foil. In some examples, sheet <NUM> is about <NUM> thick (thickness <NUM>) with an R-value that is less than that of sheets <NUM> and <NUM>. The lower R-value of sheet <NUM>, in some examples, is due to sheet <NUM> being thinner than sheets <NUM> and <NUM>.

To help hold multiple sheets <NUM> in place, in some examples, a continuous or segmented sheet <NUM> (fourth sheet) is thermally or otherwise joined to sheet <NUM> and/or baffles <NUM> to create a plurality of pockets <NUM> in which sheets <NUM> are inserted. To facilitate effective thermal bonding of sheet <NUM> with sheet <NUM> and/or baffle <NUM>, in some examples, baffles <NUM> and sheets <NUM>, <NUM>, and <NUM> each comprise polyurethane.

An example flexible door panel movable between an open position and a closed position relative to a doorway includes a first pliable sheet made of a first polymeric material. The first sheet has a first water vapor transmission rate. The example flexible door panel also includes a second pliable sheet made of a second polymeric material. The second sheet is generally parallel to the first sheet when the door is in the closed position. The second sheet has a second water vapor transmission rate. The example flexible door panel also includes a thermally insulating pad between the first sheet and the second sheet. The thermally insulating pad is resiliently compressible. The example flexible door panel also includes a third sheet between the first sheet and the thermally insulating pad. The third sheet has a third water vapor transmission rate. The third water vapor transmission rate is lower than the first water vapor transmission rate, and the third water vapor transmission rate is lower than the second water vapor transmission rate.

In some examples, the first sheet has a first R-value, the second sheet has a second R-value, and the third sheet has a third R-value. The first R-value is greater than the third R-value, and the second R-value is greater than the third R-value. In some examples, the first sheet has a first thickness, the second sheet has a second thickness, the third sheet has a third thickness. The first thickness is greater than the third thickness, and the second thickness is greater than the third thickness. In some examples, at least one of the first sheet or the second sheet includes polyurethane. In some examples, at least one of the first sheet or the second sheet defines a condensate drain hole.

In some examples, the example flexible door panel also includes a plurality of baffles connecting the first sheet to the second sheet to define a plurality of chambers between the first sheet and the second sheet. The plurality of baffles is connected to the first sheet and the second sheet at a plurality of fused joints. In some examples, the example flexible door panel also includes a plurality of thermally insulating pads disposed within the plurality of chambers. The plurality of thermally insulating pads includes the thermally insulating pad. In some examples, the third sheet encircles the thermally insulating pad. In some examples, the example flexible door panel also includes a fourth pliable sheet made of a fourth polymeric material. The fourth sheet has a fourth water vapor transmission rate that is greater than the third water vapor transmission rate of the third sheet. The fourth sheet is joined to at least one of the second sheet or the plurality of baffles to define a pocket between the fourth sheet and the second sheet. The third sheet is disposed within the pocket. The fourth sheet is interposed between the third sheet and the thermally insulating pad. In some examples, the first sheet is to be colder than the second sheet when the door is installed in the doorway of a cold storage room.

In some examples, a flexible door panel movable between an open position and a closed position relative to a doorway includes a first pliable sheet made of a first polymeric material and a second pliable sheet made of a second polymeric material. The second sheet is generally parallel to the first sheet when the door is in the closed position. The flexible door panel also includes a plurality of baffles connecting the first sheet to the second sheet to define a plurality of chambers between the first sheet and the second sheet. The plurality of baffles is connected to the first sheet and the second sheet. The flexible door panel also includes a plurality of thermally insulating pads disposed within the plurality of chambers. A thermally insulating pad of the plurality of thermally insulating pads is between the first sheet and the second sheet. The thermally insulating pad is resiliently compressible. The flexible door panel also includes a third sheet encircling the thermally insulating pad.

In some examples, the first sheet has a first R-value, the second sheet has a second R-value, the third sheet has a third R-value. The first R-value is greater than the third R-value, and and the second R-value is greater than the third R-value. In some examples, the first sheet has a first thickness, the second sheet has a second thickness, the third sheet has a third thickness. The first thickness is greater than the third thickness, and the second thickness is greater than the third thickness. In some examples, at least one of the first sheet or the second sheet includes polyurethane. In some examples, at least one of the first sheet or the second sheet defines a condensate drain hole. In some examples, the third sheet has a third water vapor transmission rate. The third water vapor transmission rate is lower than the first water vapor transmission rate, and the third water vapor transmission rate is lower than the second water vapor transmission rate.

An example flexible door panel movable between an open position and a closed position relative to a doorway includes a first pliable sheet made of a first polymeric material. The first sheet has a first water vapor transmission rate. The flexible door panel also includes a second pliable sheet made of a second polymeric material. The second sheet is generally parallel to the first sheet when the door is in the closed position. The second sheet has a second water vapor transmission rate. The flexible door panel also includes a plurality of baffles connecting the first sheet to the second sheet to define a plurality of chambers between the first sheet and the second sheet. The plurality of baffles is connected to the first sheet and the second sheet. The flexible door panel also includes a plurality of thermally insulating pads disposed within the plurality of chambers. A thermally insulating pad of the plurality of thermally insulating pads is between the first sheet and the second sheet. The thermally insulating pad is resiliently compressible. The flexible door panel also includes a third sheet between the first sheet and the thermally insulating pad. The third sheet has a third water vapor transmission rate. The flexible door panel also includes a fourth pliable sheet made of a fourth polymeric material. The fourth sheet is joined to at least one of the first sheet or at least one of the plurality of baffles to define a pocket between the fourth sheet and the first sheet. The third sheet is disposed within the pocket. The fourth sheet is interposed between the third sheet and the thermally insulating pad. The third water vapor transmission rate is lower than the first water vapor transmission rate, and the third water vapor transmission rate is lower than the second water vapor transmission rate.

In some examples, the first sheet has a first R-value, the second sheet has a second R-value, the third sheet has a third R-value, the first R-value is greater than the third R-value, and the second R-value is greater than the third R-value. In some examples, the first sheet has a first thickness, the second sheet has a second thickness, the third sheet has a third thickness. The first thickness is greater than the third thickness, and the second thickness is greater than the third thickness. In some examples, at least one of the first sheet or the second sheet includes polyurethane. In some examples, at least one of the first sheet or the second sheet defines a condensate drain hole. In some examples, the first sheet is to be colder than the second sheet when the door is installed in the doorway of a cold storage room.

An example door includes a first sheet coupled to a second sheet to define a chamber therebetween. The door also includes a thermally insulating pad within the chamber and a third sheet adjacent the thermally insulating pad to substantially prevent water vapor from permeating the thermally insulating pad. The third sheet is positioned between the thermally insulating pad and at least one of first sheet or the second sheet. In some examples, the third sheet substantially surrounds the thermally insulating pad. The door may also include a baffle and a drain hole. The baffle is coupled to the first and second sheets at a non-perpendicular angle relative to a longitudinal axis of the door when the door is in a closed position. The drain hole is defined by one of the first sheet or the second sheet adjacent the baffle to enable liquid to flow within the chamber along at least one of the baffle, the first sheet, or the second sheet through the drain hole.

Claim 1:
A flexible door panel (<NUM>) movable between an open position and a closed position relative to a doorway, the door panel comprising:
a first pliable sheet (<NUM>) made of a first polymeric material, the first sheet (<NUM>) having a first water vapor transmission rate;
a second pliable sheet (<NUM>) made of a second polymeric material, the second sheet (<NUM>) being generally parallel to the first sheet (<NUM>) when the door is in the closed position, the second sheet (<NUM>) having a second water vapor transmission rate, the first sheet (<NUM>) and the second sheet (<NUM>) being joined and generally sealed along their outer perimeter to create one large overall air chamber (<NUM>) between the first sheet (<NUM>) and the second sheet (<NUM>);
a plurality of baffles (<NUM>) dividing the air chamber (<NUM>) into a plurality of smaller chambers (<NUM>);
a thermally insulating pad (<NUM>) being installed between the first sheet (<NUM>) and the second sheet (<NUM>) in each smaller chamber (<NUM>), the thermally insulating pad (<NUM>) being resiliently compressible; and
the flexible door panel (<NUM>) being characterized in that it further comprises:
a third sheet (<NUM>, <NUM>) between the second sheet (<NUM>) and the thermally insulating pad (<NUM>), the third sheet (<NUM>, <NUM>) to abut the second sheet (<NUM>), the third sheet (<NUM>, <NUM>) having a third water vapor transmission rate, the third water vapor transmission rate being lower than the first water vapor transmission rate, and the third water vapor transmission rate being lower than the second water vapor transmission rate.