CROSS-REFERENCE TO RELATED APPLICATIONS
This application claims the benefit of U.S. Provisional Application Ser. No. 60/669,189, filed Apr. 6, 2005, and U.S. application Ser. No. 11/348,145 filed Feb. 6, 2006, which are hereby incorporated by reference in their entireties.
The embodiments herein are directed to a retractable window covering that can be manufactured from strips of material arranged in overlapping relation to cover an area of a window.
An ancient, but ever-popular form of window covering is known as a Roman shade. This type of shade conventionally includes a fabric sheet at least as wide as the window to be covered and as long as or longer than the window. A fabric is fitted with periodically-spaced rings or their equivalents on the back (outward-facing) surface of the fabric, aligned in vertical columns. Cords are passed through the rings and attached at the bottom of the fabric or sometimes to a rigid bar. When the cords are pulled (the cords being typically directed through a top rail and cord free ends of the locking device, so as to be pulled by an operator), the shade is raised, permitting view through the window and cleaning. A variant, called ‘hobbled’ adds a second set of cords or a second fabric layer with shorter periodicity, joined to the back of the first fabric, to form a sequence of billows in the front fabric. The periodic spacing of the rings causes the fabric to be taken up in sequential folds as lower rings are lifted into contact with rings just above and held together by the cord passing through. Because this type of shade is readily made from any fabric, Roman shades have been associated with expensive custom treatments made by hand in custom-chosen fabrics. As such, they are perceived as having a very desirable appearance.
In recent years, some attempts have been made to improve the manufacturability and function of Roman shades. One example is given in U.S. Pat. No. 5,566,735 to Jelic and now manufactured by Comfortex Corporation. The shade uses U-section ribs pressed onto the fabric in a spaced array, combined with snap-on beaded cords that connect to the ribs to set the billows or flat spacing of the flat fabric. Lift cords extending through eyes in the clips perform the usual Roman gathered lift. This design simplifies the assembly of a Roman shade without altering its basic appearance, but the cutting and measuring of a fabric piece and positioning of the ribs remain labor-intensive.
Other disadvantages of Roman shades include low thermal insulating value, fragility in shipping as the fabric is gathered in folds and easily crushed or creased in packaging, low solar reflectance (enhanced reflectance is often obtained, for instance in cellular shades, with a white outward surface despite choice of interior face colors), accessible cords (potential safety hazard), and an unattractively large, bulging accumulation of folded fabric when raised. The embodiments described herein address some or all of these shortcomings.
In the exemplary embodiments described, a window covering is employed having a carrier grid and a plurality of horizontal strips of fabric secured to the carrier grid. The strips are disposed in overlapping and vertically spaced relation to cover an area of a window.
BRIEF DESCRIPTION OF THE DRAWINGS
The features and inventive aspects of the present invention will become more apparent upon reading the following detailed description, claims, and drawings, of which the following is a brief description:
FIG. 1 is a perspective view of a first exemplary embodiment of a partially assembled window covering;
FIG. 2 is a perspective view of a second exemplary embodiment of a partially assembled widow covering showing material strips on a cellular backer material and internal lift cords;
FIG. 2A is a detailed side view of the window covering of FIG. 2 showing a detail area 2A of FIG. 2;
FIG. 2B is a detailed side view of the window covering of FIG. 2 showing a detail area 2B in FIG. 2A;
FIG. 2C is a perspective view of a third exemplary embodiment of a window covering showing a partially assembled window covering having lift cords not internal to the ligaments or cells and tabs extending outward from a surface of the window covering;
FIG. 2D is a detailed side view of the window covering of FIG. 2C showing a detail area 2D in FIG. 2C;
FIG. 2E is a detailed side view of the window covering of FIG. 2C showing a detail area 2E in FIG. 2D;
FIG. 3 is a side view of the window covering of FIG. 2C in an extended position showing material strips secured to the tabs by a backing clip;
FIG. 3A is a side view of the window covering of FIG. 2C in a retracted position proximate a headrail;
FIG. 4 is a perspective detailed view of a first example of a material strip having two folded-over pockets;
FIG. 5 is a perspective detailed view of a second example of a material strip having pockets formed from joining two smaller pieces of material;
FIG. 6 is a perspective detailed view of a third example of a material strip having a pocket on a first side and an attachment strip on a second side;
FIG. 7 is a perspective view of a fourth exemplary embodiment of a partially assembled window covering having a stiffener at both the upper edge and lower edge of the material strip;
FIG. 8 is a perspective detailed view of an exemplary connection between a pocket segment of the fourth exemplary embodiment of a window covering and the material strip using an elongated backing clip;
FIG. 9 is a side view of a first example of the backing clip of FIGS. 3, 3A, and 8;
FIG. 10 is a side view of a second example of the backing clip of FIGS. 3, 3A, and 8; and
FIG. 11 is a side view of a third example of the backing clip showing a larger opening adapted to receive two stiffeners.
Referring now to the drawings, illustrative embodiments are shown in detail. Although the drawings represent the embodiments, the drawings are not necessarily to scale and certain features may be exaggerated to better illustrate and explain an innovative aspect of an embodiment. Further, the embodiments described herein are not intended to be exhaustive or otherwise limit or restrict the invention to the precise form and configuration shown in the drawings and disclosed in the following detailed description.
The embodiments described herein are directed to a window covering 20 having a plurality of horizontal, overlapping and vertically-spaced material strips 22 secured to a carrier grid 24 that maintains their spacing as shown in FIG. 1. The window covering 20 may include lift cords 26 secured to a lowermost strip 28 or a rail 30 that draws up the strips 22 into a nested stack when the cords 26 are pulled in a downward direction. The lower edges 32 of the strips 22 are free-hanging, having either a plain edge or an edge with a stiffening rib, as further described below, so that the strips 22 remain free-hanging when the they are drawn up. In another example of the strips 22, the lower edges 32 of the strips 22 are secured to the carrier grid 24 also, for instance near an upper edge 34 attachment of the next lower strip 22, so as to provide a folding of each strip 22 when drawn up, and optionally, a hobbled look when the strips 22 are lowered. In the embodiment of the window covering 20 shown in FIG. 1, the free-hanging lower edge 32 of each strip 22 generally covers and overlaps the upper edge 34 of the strip directly below it.
FIG. 1 shows a partially-assembled window covering 20 of a basic type, according to a first embodiment. The material strips 22 are shown having edge stiffeners 36 secured to spacing cords 38 by engagement clips 40. A headrail 42 is disposed at an upper portion of the window covering 20 and is formed from a material such as plastic, metal, wood, polyamide resin or the like. The headrail 42 guides lift cords 44 from a cordlock 46 and pull tassels 48 through spaced drops 50 to bottom rail 30. The pull tassels 48 are provided to move the window covering 20 between an open and closed orientation, as known in the art. For ease of understanding, four upper strips and one lower strip are omitted from this partial assembly. The engagement of clips 40 to the first strip 52 and stiffener 36 can be seen at the uppermost first strip 52 shown. Further, the securement stiffener 36 of strip 22 is from an exterior orientation of spacing cords 38. In other words, the strips 22 are not secured within the spacing cords 38 so that each strip 22 may not be easily removed independently of the other strips 22. Each strip 22 is secured by the engagement clips 40 allowing a user to remove a single target strip 22 without removing the entire window covering 20 from an installed orientation or disassembling the window covering 20 in order to access the target strip 22. By providing a window covering 20 that permits the removal of a single strip 22 without removal or disassembly of the window covering 20, the user saves time and effort in the replacement of the strip 22. The engagement clips 40 may be any clipping mechanism adapted to secure the strips 22 to the carrier grid 24. In one example, the engagement clips 40 may be secured to the carrier grid 24 by molding, pressure-sensitive adhesive, heat-sensitive adhesive, stitching, clipping, or the like at a predetermined location along the vertical length of the carrier grid 24. The engagement clips 40 may be formed from plastic, polyamide resin, metal, or the like. In one illustrated example, the engagement clips 40 include the space drop 50 for guiding the cord 44 and a generally C-shaped body having a predetermined horizontal width for engaging the stiffener 36 of the strip 22. The engagement clips 40 are relatively short in horizontal width and may include any cross-section including the cross-section shown in FIG. 11 for securement of two strips 22. Furthermore, the clips 40 may include two generally C-shaped segments (not shown) for securement of an upper strip 22 and a lower strip 22 at one predetermined location along the vertical length of the window covering 20.
Referring now to FIG. 2, a second exemplary embodiment of the window covering 20 is shown. The covering 20 includes a plurality of material strips 22. Two strips 22 have been removed to reveal other parts of the covering 20 in an area 2A. The covering 20 further includes a cellular backing material 54 with internal lift cords 56. The internal lift cords 56 are similar to lift cords 44. In the second exemplary embodiment, the cellular backing material 54 is adapted to generally extend over the length of the window covering 20. Because of the weight of the bottom rail 60, cell-wall ligaments 58 are pulled downwardly into general alignment, providing a uniform pitch of exterior ligaments 58 a and 58 b so that the cell-wall ligament 58 spacing becomes generally uniform in an extended position as shown.
Cellular backing material 54 includes internal ligaments in the form tabs 59 that are disposed generally perpendicular to the generally vertical cell-wall ligaments 58. As illustrated in FIGS. 2A and 2B, the joint or seam 59 a, which forms each tab 59 may be provided by welding, sewing, gluing or other suitable methods of joining at least two materials. In one example, the joint 59 a is formed by ultrasonic welding the two pieces of material at a predetermined position, forming the joint or seam 59 a between the folded materials. Likewise, in one example, the exterior ligament 58 a is secured to its respective cell-wall ligament 58 at a predetermined location by welding, sewing, gluing or other suitable methods of joining at least two materials. The length (T) of the tabs 59 will vary with the desired application, the length T may be in the range of 0.001″ to 5/16″ and pleat sections may have a length (L) after the tabs 59 are formed in the range of ¼″ to 2″.
Each of the tabs 59 includes at least one cord hole 59 b formed therein. The exact number of cord holes 59 b will vary with the horizontal width of the covering 20 and the rigidity of the cellular backing material 54. In the exemplary embodiment of FIGS. 2, 2A, and 2B, two cord holes 59 b disposed through the tabs 59 are shown. The cord holes 59 b in the tabs 59 are aligned so that the internal lift cords 56 may pass therethrough. In addition to passing through the cord holes 59 b in tabs 59, the cords 56 enter the headrail 42 in a generally conventional fashion and pass over conventional mechanisms including locking mechanisms in the headrail 42 and out of the side thereof to control the raising and lowering of the covering 20. Cords 56 may also pass through approximately the center portion of bottom rail 60. The lower ends of cords 56 may be knotted (not shown), may be attached to rings (not shown) or washers (not shown), or may be held in bottom rail 60 in another conventional fashion. Cords 56 passing through the cellular backing material 54 permit the bottom rail 60 to hang generally straight when the shade is lowered.
In FIG. 2, the material strips 22 secured to consistently-separated cell-wall ligaments 58 also obtain a generally uniform spacing in the fully extended position. Specifically, the cellular backing material 54 includes the ligaments 58 that are under a predetermined tension by the weight of the bottom rail 60 and are generally vertical while allowing slack for the pitched exterior ligament 58 a and 58 b. The securement of the material strips 22 to the cellular backing material 54 is discussed in more detail below.
Referring now to FIGS. 2C, 2D, and 2E, a third exemplary embodiment of the window covering 20 is shown. The covering 20 includes a plurality of material strips 22. Two strips 22 have been removed to reveal other parts of the covering 20 in an area 2D. The covering 20 further includes a cellular backing material 54 with lift cords 56. The cellular backing material 54 is adapted to generally extend over the length of the window covering 20. Because of the weight of the bottom rail 60, cell-wall ligaments 58 are pulled downwardly into a generally vertical orientation, providing a uniform pitch of the exterior ligaments 58 a so that the cell-wall spacing becomes generally uniform and generally similar to the second exemplary embodiment of FIG. 2 described above.
In FIGS. 2C, 2D, and 2E, a first portion of a continuous material forms the pleat of exterior ligaments 58 a and a second portion of continuous material forms the generally vertical cell-wall ligaments 58. Generally, each exterior ligament 58 a includes tabs 59 formed between the pleats and disposed generally perpendicular to the cell-wall ligaments 58. However, the tabs 59 are flexible and may rest in any generally horizontal position. The tabs 59 are formed in a folded orientation as shown in FIG. 2E by at least one of the first portion of material that forms the exterior ligaments 58 a and the second portion of material that forms the cell-wall ligaments 58. The joint or seam 59 a that forms the tabs 59 may be provided by welding, sewing, gluing or other suitable methods. In one example, the joint 59 a is formed by ultrasonic welding the two pieces of material at a predetermined position forming the joint or seam 59 a between the folded materials. Further, the stiffener 36 may be disposed within the joint 59 a between the folds of either the first portion of material or the second portion of material for securing at least one strip 22 to the cellular backing material 54 as shown in FIGS. 3 and 3A. As discussed above, the length (T) of the tabs 59 will vary with the desired application; the length T may be in the range of 0.001″ to 5/16″ and pleat sections may have a length (L) after the tab 59 is formed in the range of ¼″ to 2″. The tab 59 counterbalances the pleat and thereby improves the appearance and operation of the cellular backing material 54.
As shown in FIGS. 3, 3A, and 4, the stiffener 36 may be included at the lower edge 32 of each strip 22 to maintain its general vertical orientation and uniformity and to prevent excessive flapping of the strip 22 in a breeze. Attachment to the cellular backing material 54 by any known method such as adhesive, stitching, clamping, fastening, and the like provides securement of the upper edge 34 of the strip 22. Further, the stiffener 36 may be included in the upper edge 34 for securing the strip 22 to the cellular backing material as further discussed below. The combination of cellular backing material 54 and the material or strip 22 provides excellent thermal insulation.
FIG. 3 is a partial side view of the window covering 20 of FIG. 2C showing the window covering in the extended position having the strips 22 secured to the tabs 59 by a backing clip 74. The backing clip 74 is described in more detail below and is illustrated enlarged for clarity. As illustrated in FIGS. 3 and 4, the strip 22 includes a stiffener 36 at both the lower edge 32 and the upper edge 34. The lower edge 32 of the strip 22 generally covers the upper edge 34 of the strip 22 above it in the extended position. The vertical length of the strip 22 may be varied depending on the user's requirements. The strip 22 is shown to be secured to every second tab 59 at a securement point. However, the predetermined vertical length of the strip 22 dictates the number of tabs between securement points. The tab 59 may include a stiffener 36 for attaching the backing clip 74. The stiffener may be disposed between the material that forms the exterior ligaments 58 a or between the material that forms the cell-wall ligaments 58 at the tab 59. In FIG. 3A, the window covering 20 of FIG. 2C is shown in a retracted position having the upper edges 34 of each strip 22 relatively closer than in the extended position of FIG. 3.
FIG. 4 is a detail view of a first exemplary embodiment of the material strip 22 of FIGS. 1, 2, and 2C. The material strip 22 includes edge pockets 64 that may be formed by folding the lower edge 32 and upper edge 34 of the strip 22 and joining each portion at an attachment area 66. Any joining method may be used including sewing, using an adhesive, adhesive heat welding, stitching, mechanically attaching and the like. The strip 22 may be laminated or include a printed material that presents a white or reflective face on one side and an attractive color or texture on the other side.
FIG. 5 is a detail view of a second exemplary embodiment of the material strip 22 of FIGS. 1, 2, and 2C. The material strip 22 includes a face material 68 and may include at least a partially-laminated back material 70. The material may be fabric, plastic, vinyl, polyester, a woven and non-woven film, or the like. Attachment areas 66 are adapted to form pockets 64 and may be formed by any joining method including sewing, using an adhesive, adhesive heat welding, stitching, mechanically attaching or the like. The back material may be white for reflectivity or any color for uniformity.
FIG. 6 is a detail view of a third exemplary embodiment of the material strip 22 of FIGS. 1, 2, and 2C. The material strip 22 includes the face material 68, at least one stiffener 36, and at least one attachment strip 72. The stiffener 36 is disposed inside pocket 64 between attachment areas 66. The attachment strip 72 is shown to be secured to the upper edge 34. However, the attachment strip 72 may be secured to the strip 22 at any location along the horizontal width of the strip 22 by any known attachment method, including using pressure-sensitive or heat-sensitive adhesive, stitching, and the like.
FIG. 7 is a fourth exemplary embodiment of a window covering 20. The window covering 20 includes stiffeners 36 at both the upper edge 34 and the lower edge 32. Each edge 34, 32 is secured to the carrier grid 24. The carrier grid 24 may include spacing cords 38 or a cellular backing material 54 as shown in FIGS. 2 and 2C and described above. When the vertical width of the strip 22 is greater than the distance between engagement clips 40, represented by grid pitch P, the strips 22 form billows 72 a and resemble conventional hobbled Roman shades. When the vertical width of the strip 22 is generally the same length as grid pitch P, then the strip 22 resembles a conventional flat Roman shade. In one example, the stiffeners 36 engage one another within the engagement clip 40. The upper edge 34 of a first strip 22 having a first stiffener 36 abuts the lower edge 32 of an adjacent strip 22 having a second stiffener 36. This can be achieved, for instance, by making the strips 22 interlocking along their length. Alternatively, the stiffeners 36 may be adjacent and clipped together by the carrier grid 24. Where the carrier grid 24 is cellular material, one or both of the edge stiffeners 36 may be omitted.
FIG. 8 is a detailed view of a fourth exemplary embodiment of a window covering 20. Specifically, FIG. 8 illustrates a detailed view of an exemplary connection between a pocket segment 73 of the cellular backing material 54 using an elongated backing clip 74 and the material strip 22. The elongated backing clip 74 may have any length from the horizontal width of the window covering 20 to any predetermined length desired by the user. The pocket segment 73 represents any ligament including exterior ligaments 58 a and 58 b of FIGS. 2-3A. The backing material 54 includes a plurality of pocket segments 73. A section of cellular backing material 54 is shown securing one material strip 22. The material strip 22 includes the face material 68 projecting in a downward direction from the backing clip 74. The stiffener 36 is disposed within the pocket 64 thereby securing the strip 22 to a first elongated body portion 76 of the backing clip 74. A second elongated body portion 78 of the backing clip 74 is secured to the cellular backing material 54 by a stiffener 36 placed inside the pocket segment 73 and secured within the second portion 78 of the backing clip 74. The backing clip 74 captures the cellular backing material 54 at a predetermined line of connection. A first portion opening 80 is sized to secure the strip 22 and the stiffener 36 and minimize any slipping between the strip 22 and the backing clip 74. A second portion opening 82 is sized to secure the pocket segment 73 to the backing clip 74 and minimize distortion of the cellular backing material 54. However, there are other attachment methods that may secure the material strip 22 to the pocket segment 73 including clipping, welding, sewing, gluing or other suitable methods.
In operation, the backing clip 74 is slid over the pocket 64 and stiffener 36, thereby securing the strip to the backing clip 74. The backing clip 74 is then slipped over the pocket segment 73 and stiffener 36, thereby securing the backing clip to the cellular backing material 54. As shown in FIGS. 9 and 10, to enable the above described assembly, the backing clip 74 includes at least two receiving openings: the first portion opening 80 and the second portion opening 82. A first portion mouth 84 is configured to allow the stiffener 36 and pocket 64 to pass through during installation while providing securement of the stiffener 36 and pocket 64 in the installed orientation. A second portion mouth 86 is configured to allow the stiffener 36 and a portion of the pocket segment 73 to pass through during installation while providing securing of the stiffener 36 and the pocket segment 73 in the installed orientation. The first portion 76 and the second portion 78 are shown to be generally perpendicular to one another. However, any angle between the first portion 76 and the second portion 78 is contemplated. FIG. 9 shows a first portion 76 generally larger than the second portion 78, and FIG. 10 shows the first portion 76 to be generally equal in size to the second portion 78. However, any combination of the first portion 76 and the second portion 78 is contemplated. Furthermore, in yet another example, one or both ends of the openings 80, 82 may be sealed, either at the time of segment cutting to length or later to retain the stiffeners 36. For material segments, cutting to length may be done with a sealing cutting. By way of example, hot wire cutters, ultrasonic cutters, and the like may be used to seal the pocket ends at generally the same time. A small slit (not shown) may also be made in the backside of the pocket 64 to insert the stiffener 36.
Three distinct appearances are achieved by the exemplary embodiments described above: hobbled, flat-continuous, and flat-shingled. One example includes having the hobbled appearance as illustrated in FIG. 7. The clip 74 (not shown) or 40 is disposed at both the lower edge 32 and the upper edge 34 of each strip 22, with the lower edge 32 secured to a pocket segment 73 (not shown) at generally the same location (the clips 74 or 40 being proximate one another) as the upper edge 34 of the next lower strip 22, and at a distance smaller than the vertical width of the strip 22, such that each strip 22 bows out over the next lower strip 22, at least generally covering the clip 74, 40 with a billow. Another example of the hobbled appearance includes providing a continuous material having stiffeners 36 disposed at predetermined locations along the vertical length of the material for securing to the clips 74 or 40 disposed along the vertical length of the window covering 20 in the same manner described above. Yet another example of the hobbled appearance includes providing the clip 74 or 40 having a cross-section of the exemplary embodiment of FIG. 11 for selectively securing both the upper edge 34 of a first strip 22 and the lower edge 32 of a second strip as illustrated in FIG. 11 and further described below. For the flat-continuous application formed from strips 22, two smaller-diameter stiffeners 36 may be used to fit the lower edge 32 of one strip 22 and the upper edge 34 of the adjacent strip 22 into a single larger opening 80 of clip 74 as shown of FIG. 11 showing two adjacent strips 22 sharing the opening 80. Alternatively, the clips 74 and 40 may have three pockets (not shown), with the two pockets for adjacent strips 22. Further, the strip 22 may be secured to the carrier grid 24 by any method including molding, pressure-sensitive adhesive, heat-sensitive adhesive, stitching, clipping, or the like.
As will be clear to one skilled in the art, the described embodiments, though having the particular advantages of compactness and convenience, are not the only embodiments or arrangements that fall within the scope of the present invention. Some exemplary variants may include: a) use of a pleated grid in place of the cellular backing material 54 for spacing; b) using external instead of internal, pocketed stiffeners 36; c) including quilted or other multi-layer material strips 22; d) having non-linear (wavy or scalloped) free edges 32, 34 on strips 22, especially for the flat-shingled embodiment; e) using rigid or resilient, stiff strips 22 instead of a fabric material, especially on the flat-shingled embodiment where the strips 22 are generally flat; f) having top-down instead of bottom-up actuation; and g) the use of two spacer cords in the hobbled embodiment, instead of one set sharing attachments, whereby raising the spacer set attached to the lower edges 32 of the strips 22 provides a Venetian-like view-through mode by opening gaps between adjacent strips 22.
The embodiments described above offer a number of advantages over various prior art shades. Some of these advantages are aesthetic and others are practical, either in manufacturing cost or serviceability of the end product. Below are some exemplary elements of the described embodiments with notes of comparison to earlier approaches.
Rollable strips: The strips 22 as described above could provide the appearance and function of a single sheet covering an entire window; but are made instead from controlled strips 22 of material allowing efficient use of goods and minimal scrap in fabrication. Strips 22 (before insertion of stiffeners 36) also ease packaging and stock storage before fabrication because they can be stored in rolls. Damage is easily replaced at minimal cost, rather than losing the entire window covering 20.
Fast assembly: In comparison to the handling of a conventional Roman window covering, made from a single, large sheet of material equal in extent to a window, a strip-fabricated system can be built rapidly with minimal floor space demand and convenient equipment. No large flat cutting table is required. No marking and measuring of the broad goods is required to locate multiple rings or other attachments that are automatically located by the dimensions intrinsic to the strips.
Insulation: By comparison to ordinary Roman window coverings, the cellular-backed embodiments provide multiple air cells behind the facing to significantly increase the thermal insulation value of the product.
White back: In modern homes, interior rooms are commonly decorated in different colors, yet the house presents a more formal, uniform face to the outside world. Products which can present a white outer face sustain that uniformity, even as the interior faces carry differing room colors. Many condominium and homeowner associations require a uniform external appearance of window treatments. The embodiments described above enable such a dichotomy through their layered or laminated construction.
Cord contained: Safety is a primary concern in the window coverings 20. One of the primary risks is associated with accessible cords that can entangle small children in a choking hazard. The cellular-backed embodiments fully encapsulate the cords that lift the covering 20 within the cells, unlike any other Roman-style product, reducing that hazard. The second example of the cellular backed embodiment shown in FIG. 2C, though not completely encapsulating cords, nonetheless shields them from accidental entanglements by enclosing them between the strips 22 and backing material 54.
View-through option: Conventional Roman-look shades are made from continuous material. The embodiments described, by mimicking the look of such a continuous piece, although made from multiple strips, offer the option of independent articulation of those strips to allow a view-through mode more like that of a Venetian blind.
Multiple product looks from same stock: The embodiments described may all be assembled from the same basic parts (material strips, cord or cellular backing material, and hardware), providing a significant economy of scale and lower stock-carrying costs for fabricators and retailers. This latter feature is of particular importance in lowering the costs of such custom-made window treatments through direct finishing at the retail level and elimination of one level in the distribution.
Multiple product looks from assembly of different strips: The embodiment descried may all be assembled from multiple strips 22, each having a different color or style of fabric providing flexibility for the user to be more creative with the assembly of the strips 22.
Low waste from strip construction, including flaw removal and cutting efficiency: When large rectangles must be cut from yard goods, as in the conventional Roman process, there is always a higher waste factor as differing sizes of rectangle are fitted to finite-width goods. In the embodiments described, continuous ribbon is cut to strips of window size, with little or no waste between succeeding strips. Even when a flaw occurs in the ribbon, the loss can be no more than the length of one strip, where in a broadgoods cutting, an inconveniently located flaw can prevent the usage of a large area of fabric.
Unlimited width and length: In conjunction with to the low waste with ribbon-strip construction comes the better orientation of raw material run with respect to finished product dimension. If cut from broad goods, either the vertical length or horizontal width is constrained by the horizontal width of the source material. With ribbons to strips, the unlimited length of their ribbons (corresponding to the production run direction of the original material) is oriented to the width of the window covering 20 and so can provide unlimited width to the shade. Because the window covering 20 length is then built up from unlimited numbers of such strips, the length of the shade, too, is unlimited. This is becoming more important in modern homes where “window walls” are part of the design: high and wide glass areas too large for conventional window coverings.
Ready replacement of damaged or soiled areas without total loss: This is another feature of economy and convenience that derives from the strip construction. Not being a single expanse of material, a window covering 20 may be repaired at low cost by replacing only those strips 22 that suffer damage or discoloration in service. With some materials, it may even be possible to remove individual strips 22 for cleaning and replacement.
The present invention has been particularly shown and described with reference to the foregoing embodiments, which are merely illustrative of the best modes for carrying out the invention. It should be understood by those skilled in the art that various alternatives to the embodiments of the invention described herein may be employed in practicing the invention without departing from the spirit and scope of the invention as defined in the following claims. It is intended that the following claims define the scope of the invention and that the method and apparatus within the scope of these claims and their equivalents be covered thereby. This description of the invention should be understood to include all novel and non-obvious combinations of elements described herein, and claims may be presented in this or a later application to any novel and non-obvious combination of these elements. Moreover, the foregoing embodiments are illustrative, and no single feature or element is essential to all possible combinations that may be claimed in this or a later application.