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You are an expert at summarizing long articles. Proceed to summarize the following text: 
REFERENCE TO RELATED APLPICATIONS 
       [0001]    This patent application claims priority to U.S. Provisional Patent Application No. 62/309,112, the entire contents of which is hereby incorporated by reference. 
     
    
     BACKGROUND 
       [0002]    The present invention relates generally to window coverings and window coverings that are adjustable in size. 
         [0003]    Options available to consumers for obtaining Roman shades are somewhat limited. Custom sized Roman shades can be ordered to fit a specific window dimension. Custom ordering can result in delay, and the costs for ordering custom size Roman shades can be high. Many retail outlets offer stock size Roman shades for immediate purchase, but the selection available is limited. Accordingly, it is often difficult for a consumer to achieve a satisfactory fit with the stock sizes available. In many cases, stock Roman shades will be oversized to mount outside the window frame. While many types of window coverings are available through programs featuring stock sizes custom cut to a consumer&#39;s specifications at the point-of-sale, due to the nature of and materials used for Roman shades, cutdown programs have not featured Roman shades. Accordingly, consumers have had only two options, custom ordering with delay and additional expense or stock sizes that may not fit as desired. 
         [0004]    There is a need for a customizable Roman shade that can be sized like a custom blind yet available the same day like a stock or cutdown blind. 
       SUMMARY 
       [0005]    The present invention provides a window covering comprising a head rail adapted to be mounted adjacent a window, first and second panels in lateral overlapping relation to each other, each panel having an upper portion secured to the head rail, a first bottom rail secured to a lower portion of the first panel, and a second bottom rail secured to a lower portion of the second panel. The first and second bottom rails engage each other (e.g., slidably) to form a bottom rail assembly having an axial length, and a position of the first bottom rail relative to the second bottom rail is adjustable to adjust the length of the bottom rail assembly. Preferably, the first bottom rail includes a downwardly opening track, the second bottom rail includes an upwardly opening track, and the downwardly opening track slidably engages the upwardly opening track. 
         [0006]    In one embodiment, the window covering further comprises a third panel positioned in overlapping relation to the second panel (the third panel having an upper portion secured to the head rail), and a third bottom rail secured to a lower portion of the third panel. The third bottom rail engages the second bottom rail and is part of the bottom rail assembly. A position of the third bottom rail relative to the second bottom rail is adjustable (e.g., slidably) to adjust the length of the bottom rail assembly. Preferably, the first and third panels are spaced from each other by a gap, and the window covering further comprises a first rod (e.g., a rear rod) coupled to both the first panel and the third panel and spanning the gap between the first and third panels. The window covering can further comprise a second rod (e.g., a front rod) coupled to the second panel. 
         [0007]    A double rod clip can be used to connect the first rod to the second rod. Preferably, the double rod clip engages the first rod in the gap between the first and third panels. Single rod clips can be used to secure the first and third panels to the first rod. Each of the rod clips preferably includes a cord guide for guiding and retaining a corresponding lift cord. 
         [0008]    The invention also provides a method of assembling a window covering like the one described above. The method includes shortening (e.g., cutting) the length of the headrail to a first desired length, adjusting an amount of overlap between the first and second panels (e.g., by sliding at least one of the panels relative to the headrail), and moving (e.g., sliding in a telescopic manner) the first bottom rail relative to the second bottom rail to change a length of the bottom rail assembly to a second desired length (e.g., equal to the first desired length). If a third panel and third bottom rail are present, then the method can further include adjusting an amount of overlap between the second and third panels, and moving the third bottom rail relative to the second bottom rail. 
         [0009]    Other aspects of the invention will become apparent by consideration of the detailed description and accompanying drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0010]      FIG. 1  is a rear perspective view of a Roman shade embodying the present invention in the lowered position. 
           [0011]      FIG. 2  is the rear perspective view of  FIG. 1  with the shade in the raised position. 
           [0012]      FIG. 3  is an exploded rear perspective view of the Roman shade of  FIG. 1 . 
           [0013]      FIG. 4  is a rear perspective view of a portion of a headrail of the Roman shade of  FIG. 1 . 
           [0014]      FIG. 5  is a perspective view of a middle portion of the Roman shade of  FIG. 1 . 
           [0015]      FIG. 6  is an exploded perspective view of the Roman shade shown in  FIG. 5 . 
           [0016]      FIG. 7  is a front perspective view of a bottom rail assembly of the Roman shade of  FIG. 1 . 
           [0017]      FIG. 8  is a perspective view of a bottom rail of the Roman shade of  FIG. 1 . 
           [0018]      FIG. 9  is a view of a cord attached to a side panel of the Roman shade of  FIG. 1 . 
           [0019]      FIG. 10  is a bottom view of the cord attached to the side panel of  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Before any embodiments of the invention are explained in detail, it is to be understood that the invention is not limited in its application to the details of construction and the arrangement of components set forth in the following description or illustrated in the following drawings. The invention is capable of other embodiments and of being practiced or of being carried out in various ways. 
         [0021]    Referring now more particularly to the drawings, the illustrated Roman shade  100  includes a headrail assembly  102 , a fabric panels section  104 , a bottom rail assembly  106 , and lift cords  108 . Each of the headrail assembly  102 , the fabric panels section  104  and the bottom rail assembly  106  is horizontally customizable to provide custom widths within a limited range. 
         [0022]    The headrail assembly  102  includes a generally rectangular headrail  110  defining a continuous channel  112  for receiving and holding a plurality of cord motors  114 , one such cord motor  114  for each lift cord  108  of the shade  100 . Suitable cord motors and the manner for using them are well known to those skilled in the art and will not be described in further detail herein. Alternatively, the motors can be eliminated, and the cords  108  can be manually actuated. The cord motors are axially slidable along the channel  112  defined in the headrail  110 . The headrail  110  further defines a continuous retention slot  116  at the front thereof for receiving and securing the fabric panels section  104  in an axially adjustable manner. As used herein, “axially” refers to a direction parallel to the longitudinal extent of the headrail  110 . Decorative end caps  118  are provided for the ends of the headrail  110 . The headrail  110  is connectable to a plurality of mounting brackets  122  that are attachable to a window structure. Mounting of the headrail  110  using such brackets  122  to secure the location and positioning of a shade is well known to those skilled in the art. 
         [0023]    The fabric panels section  104  includes first, second, and third panels  130 , 132 , 134  having the tops thereof secured to the headrail  110 . Specifically, each of the panels  130 , 132 , 134  includes a stiff upper spine  136  (e.g., made of wood, cardboard, or plastic) bonded or otherwise secured to an upper edge of the corresponding panel, and each upper spline  136  is slid axially into the retention slot  116  of the headrail, as generally shown in  FIG. 4 . The panels  130 ,  132 ,  134  are overlapping, with the second panel  132  overlapping the inner ends of the first and third panels  130 ,  134 . Accordingly, by sliding the upper splines  136  in the retention slot  116 , the axial position of each of the first and third panels  130 ,  134  is adjustable behind the second panel  132  to vary the overall width of the fabric panels section  104 . Each of the panels  130 , 132 , 134  further includes a stiff lower spine  138  (e.g., made of wood, cardboard, or plastic) bonded or otherwise secured to a lower edge of the corresponding panel, and each lower spline  138  is secured to the bottom rail assembly  106 , as described below in more detail 
         [0024]    Referring to  FIG. 7 , the bottom rail assembly  106  includes first, second, and third bottom rails  140 , 142 , 144  that telescopically overlap with each other, with the inner ends of the first and third bottom rails  140 , 144  received in and sliding behind the second bottom rail  142 . Each of the bottom rails  140 , 142 , 144  includes a continuous retention slot  145  for receiving and securing a corresponding fabric panel  130 , 132 , 134  and in an axially adjustable manner. Specifically, the lower spline  138  of each fabric panel  130 , 132 , 134  can be slid axially into the corresponding bottom rail  140 , 142 , 144 , respectively, as shown in  FIG. 8 . 
         [0025]    As best shown in  FIGS. 1 and 3 , widths of the illustrated bottom rails  140 , 142 , 144  correspond to the widths of the corresponding first, second, and third panels  130 , 132 , 134 . Referring to  FIGS. 3, 7, and 8 , a large endcap  146  is provided on the outer end of each of the first and third bottom rails  140 , 144 , and two small end caps  148  are provided on the ends of the second bottom rail  142  to close the exposed ends of the bottom rails  140 , 142 , 144 . 
         [0026]    The bottom rails  140 , 142 , 144  engage each other in sliding relationships to form a continuous bottom rail assembly  106  at the bottom edge of the fabric panels section  104 . To establish the sliding engagement between the bottom rails  140 ,  142 ,  144 , the first and third bottom rails  140 , 144  define a downwardly oriented tracks  160 , and the second bottom rail  142  defines an upwardly oriented track  162 . Axially extending ridges  166  are provided on the inside of each of the tracks  160 , 162  to facilitate snug engagement between the tracks of the bottom rails  140 , 142 , 144  to retain the relative positioning after adjustment. 
         [0027]    Each of fabric panels  130 , 132 , 134  defines horizontally extending pleats  168 . To secure and control the registration of the pleats  168  from one fabric panel to the next fabric panel, each of the illustrated panels  130 , 132 , 134  includes pairs of rods  170 , 172  inserted into sewn loops of fabric in the panels  130 , 132 , 134 . One rod of each rod pair is a long rod  170  that extends from the pleat  168  of the first fabric panel  130  into the pleat of the third fabric panel  134 , resulting in apportion of the long rod  170  being exposed in a gap  174  between the first and third panels  130 , 134 . The other rod of each rod pair is a short rod  172  that extends through the pleat of the second fabric panel  134 . 
         [0028]    In order to secured the horizontal alignment of the rods  170 , 172 , each rod pair includes a double rod clip  176 , as shown in  FIGS. 5 and 6 . Each double rod clip  176  includes a front passage  178  for receiving the short rod  172  and corresponding pleat material from the second panel  132 , and a rear passage  180  for receiving the long rod  170 . If desired, a fastener such as a screw can be threaded through the double rod clip  176  to further secure the position of the double rod clip  176  relative to the rods  170 , 172 . Although the rear passage  180  is shown as an open passage that allows the double rod clip  176  to be slid over the side of the long rod  170 , the rear passage  180  could instead be a closed passage that requires the long rod  170  to be slid axially through the rear passage  180 . 
         [0029]    Each rod pair further includes two single rod clips  182  that each have a single passage  184  for receiving the long rod  170  and corresponding pleat material from the first and third panels  130 , 134 , as shown in  FIGS. 5 and 6 . If desired, fasteners such as screws can be threaded through the single rod clips  182  to further secure the position of the single rod clips  176  relative to the long rod  170 . 
         [0030]    Each of the double and single rod clips  176 , 182  includes a cord guide  186  for guiding and retaining the position of the corresponding lift cord  108  relative to the pleats. Specifically, each lift cord  108  extends downwardly from the headrail  110  (e.g., from a manual or powered spool or pulley system, as is known in the art) and passes through the corresponding series of aligned cord guides  186  and is secured to the bottom rail assembly  106 . In the illustrated embodiment, there is one lift cord for each of the three panels, but it should be understood that other numbers of lift cords and panels can be used. 
         [0031]    Referring to  FIGS. 9-10 , each lift cord  108  is secured to the bottom rail assembly  106  by a cord fastener  188  secured to the lower end of the corresponding panel. Specifically, an eyelet  190  is inserted through the lower end of the fabric panel and corresponding lower spline  138 , and the cord fastener  188  is inserted through and retained in the eyelet. The cord fastener  188  and eyelet  190  are sufficiently thin that they can be slid into the retention slot  145  of the corresponding bottom rail segment  140 , 142 , 144 . In the fully assembled condition, only the uppermost end of the cord fastener  188  is visible above the bottom rail segment, as shown in  FIGS. 1 and 2 . 
         [0032]    Roman shades as described above can be provided in a few specified sizes to provide custom sized shades within a range. To achieve a desired shade size, an appropriate stock size is selected. The headrail  110  is cut to the required length in an appropriate cutdown machine. It is anticipated that headrails similar to those used in the window coverings of other cutdown programs can be used for the Roman shade described herein so that the headrail can be cut in existing cutdown machines used for other cutdown programs. 
         [0033]    In order to cut down the axial length of the Roman shade  100 , the first and third fabric panels  130 ,  134  are slid toward the second fabric panel  132  so that the upper edges of the fabric panels contained in the retention slot  116  are moved away from the end portions of the headrail  110 . The cord motors  114  are also moved toward the center of the headrail  110 , thereby leaving end portions of the headrail  110  empty and suitable for cutting. Preferably, equal portions are cut from each end of the headrail  110  to achieve the desired final width. However, cutting from just one or the other end of the headrail  110  also can be performed. After the headrail is cut to the desired width, the first and third fabric panels  130 ,  134  are slid laterally outward to the maximum remaining width of the headrail  110 . Generally, it is desirable to center the second panel  132  in the final assembly. While moving the fabric panels, the cord motors  114  can be moved as required to remain in vertical alignment with the lift cords and cord guides  186  attached to the fabric panels  130 , 132 , 134 . The telescopic arrangement of the bottom rails  140 ,  142 ,  144  is adjusted so as to align each of the bottom rails with the corresponding fabric panel. 
         [0034]    In this way, a custom sized Roman shade can be provided with sizing performed at the point-of-sale to provide a consumer with the desired shade immediately at a specified size. 
         [0035]    Various features and advantages of the invention are set forth in the following claims.

Summary:
A window covering comprises a head rail, first and second panels, and first and second bottom rails secured to the first and second panels. A position of the first bottom rail relative to the second bottom rail is adjustable. A third panel can be provided, and a third bottom rail can be secured to a lower portion of the third panel. A position of the third bottom rail relative to the second bottom rail is adjustable. A first rod can be coupled to both the first panel and the third panel to span a gap therebetween. A second rod can be coupled to the second panel. A double rod clip can connect the first rod to the second rod. Single rod clips can secure the first and third panels to the first rod. Each of the rod clips preferably includes a cord guide for guiding and retaining a corresponding lift cord.