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CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application relates to and claims the benefit of prior U.S. Provisional Patent Application No. 60/352,908 entitled  Removable Louver and Tilt Control , filed Jan. 29, 2002, is incorporated by reference herein. 

   BACKGROUND OF THE INVENTION 
   Shutters are a high quality interior window treatment, having a combination of style, functionality and elegance that sets them apart from other window coverings. Shutters provide warmth in the winter and protect from damaging heat and sunlight in the summer. Shutters also provide complete control of view, privacy and light. 
   SUMMARY OF THE INVENTION 
     FIGS. 1-2  illustrate a shutter  100  having stiles  110 , spreaders  120 , louvers  140  and a tilt bar  140 . As shown in  FIG. 1 , the shutter  100  is installable within a window opening and operable to control the amount of light entering a building interior and to maintain the privacy of the building occupants, in a manner that is well known in the art. The stiles  110  are attached to the spreaders  120  so as to form a shutter frame having a generally rectangular opening. The louvers  130  are rotatably mounted to the stiles  110  within the frame. The tilt bar  140  is linked to the leading edges of the, louvers  130  and operable up and down so as to rotate the louvers to various positions. The shutter  100  has a closed position (shown) with the tilt bar  140  in a fully up position and the louvers  130  overlapping along the edges so as to block light from passing. The shutter  100  also has various open positions (not shown) with the tilt bar  140  positioned away from the fully up position and the louvers  130  rotated so as to allow light to pass. 
   As shown in  FIG. 2 , the louvers  130  are rotatably mounted to the stiles  110  using louver pins  210 . One or more selected louvers  130  receive a pair of standard roundhead screws  230  instead of a louver pin  210 . The screws  230  function as an adjustable louver tension control. The tilt bar  140  is attached to an edge of each of the louvers  130  with an interlocked tilt bar link  240  and louver link  250 . 
   A disadvantage of a shutter  100  is that louver tilt control utilizes a tilt bar that is located within the shutter frame  110 ,  120  field-of-view. Another disadvantage of the shutter  100  is that shutter frame disassembly is needed to replace a damaged louver  130 . A shutter that overcomes some of the disadvantages of conventional shutters is described in U.S. patent application Ser. No. 09/954,541 entitled  Prefinished Medium Density Fiberboard Shutter ,invented by the inventor of the current application and incorporated by reference herein. One aspect of a removable louver and tilt control is a tilt control adapted to rotate a louver between at least a partially open position and a partially closed position within a shutter frame. The tilt control comprises a stile adapted as a portion of the shutter frame and a gear rotatably retained within the stile. A rack is slideably retained within the stile. The gear engages the rack so that linear movement of the rack causes a corresponding rotation of the gear. The louver is removably connected to the gear so that rotation of the gear rotates the louver. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a perspective view of a shutter having a tilt bar; 
       FIG. 2  is an exploded perspective view of a shutter having a tilt bar; 
       FIG. 3  is an exploded perspective view of a shutter having louver end caps that provide removable louvers and a segmented link bar that provides tilt control; 
       FIG. 4  is an exploded perspective view of a shutter portion having removable louvers and a rack and gear stile assembly; 
       FIGS. 5A-B  are assembled and exploded perspective views, respectively, of a rack and gear stile assembly having geared louver end caps, segmented stile inserts, a toothed groove strip and a tilt control lever; 
       FIGS. 6A-B  are inside and outside perspective views, respectively, of a full groove stile having a secondary groove; 
       FIGS. 7A-E  are front, side, perspective, bottom end and detailed perspective views, respectively, of a toothed strip; 
       FIGS. 8A-D  are front, side, perspective and bottom end views, respectively, of a segmented insert; 
       FIGS. 9A-B  are inside and outside perspective views, respectively, of a geared louver end cap that provides for a removable louver; 
       FIGS. 10A-C  are front perspective, back perspective and side views, respectively, of a tilt control louver; 
       FIGS. 11A-B  are assembled and exploded perspective views, respectively, of a rack and gear stile assembly having geared louver end caps, segmented stile inserts, segmented sliders and a tilt control knob; 
       FIGS. 12A-E  are front, side, back, perspective and bottom end views, respectively, of a segmented slider; 
       FIGS. 13A-B  are assembled and exploded perspective views, respectively, of a rack and gear stile assembly having geared louver end caps, segmented stile inserts, stackable sliders and a tilt control lever; and 
       FIGS. 14A-D  are front, side, perspective and bottom end views, respectively, of a stackable slider. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     FIG. 3  illustrates a shutter  300  having full groove stiles  310 , spreaders  320 , stile inserts  330 , segmented link bars  340 , and louver end caps  350 ,  360 . The segmented link bars  340  advantageously eliminate the need for a tilt bar  140  (FIGS.  1 - 2 ), clearing the field-of-view. The louver end caps  350  advantageously provide for removable louvers  370 , which allow the repair or replacement of broken or damaged louvers without disassembly of the shutter frame  310 ,  320  and ease louver cleaning. The full groove stile  310  has an end to end groove  312 , which can be cut in a single manufacturing step across several stiles as compared with end-proximate partial grooves  114  (FIG.  2 ). The end-to-end groove  312  accommodates a stile insert  330  that includes pin holes  332 , which eliminates the manufacturing steps required for drilling pin holes  112  ( FIG. 2 ) along the stile  110  (FIG.  2 ). A louver end cap  350  is adapted to removably retain a louver  370 . A snap-fit stile button  352  is adapted to press fit into and lock inside an insert pin hole  332  so that a louver  370  can be removably installed between stiles  310 . A snap-fit link bar button  354  is adapted to press fit into and hold within a link bar hole  342  so that a link bar  340  can connect multiple louvers  370 . In one embodiment, the snap-fit buttons  352 ,  354  extend normally from a face of the end cap  350  and have a catch that snaps and locks inside a pin hole  332  or link bar hole  342 , respectively. 
   The capped louvers  370  advantageously reduce manufacturing steps and parts by eliminating pin holes  112  (FIG.  2 ), louver pins  210  (FIG.  2 ), link holes  260  ( FIG. 2 ) and associated links  240 ,  250  (FIG.  2 ). Screw holes can be pre-drilled in one or more selected louvers  370  so as to provide louver tension control, as described above. In that case, louver caps  360  are installed with screw holes  362  in place of snap-fit buttons  352 . The louvers  370  are opened and closed by moving an individual louver, which moves all louvers  370  via the link bars  340 . A shutter embodiment having full groove stiles, stile inserts, louver end caps, removable louvers and extended link bars is described in detail in U.S. patent application Ser. No. 09/954,541, cited above. 
   As shown in  FIG. 3 , the segmented link bar  340  is advantageously configured to attach on alternating opposite ends of overlapping louver groups so that all louvers  370  are effectively linked together. For example, each link bar may have a length sufficient to attach to a group of three louvers. Five louvers may then be linked together as two overlapping groups of three louvers, using one link bar segment each to attach to opposite louver ends, as shown. Multiple segmented link bars  340  advantageously have better rigidity than a single, extended link bar of the same length. Further, link bar segments having a standardized length can accommodate shutters having various numbers of louvers. Described below are rack and gear stile assemblies providing alternative removable louver and tilt control embodiments to the extended link bar or segmented link bar embodiments described above. 
     FIG. 4  illustrates a shutter portion  400  having spreaders  410 , louvers  420  and a stile assembly  500 . The spreaders  410  are fixedly attached to the stile assembly  500  to form a shutter frame. The stile assembly  500  accommodates end caps  900  that provide for removable louvers  420 , such as described above. The stile assembly  500  also incorporates a rack and gear tilt control for the louvers  420  that does not block the field-of-view. In one embodiment, the end caps  900  extend through stile inserts  800  and engage a toothed strip  700  installed within the stile  600 : This embodiment is described in detail with respect to  FIGS. 5-10 , below. Alternative rack and gear stile assembly embodiments are described with respect to  FIGS. 11-14 , below. 
     FIGS. 5A-B  illustrate a stile assembly  500  having a full groove stile  600 , a toothed groove strip  700 , segmented stile inserts  800 , and geared end caps  900 . Alternatively, the stile assembly  500  has a single stile insert that extends a substantial portion of the stile groove  610  ( FIGS. 6A-B ) in lieu of segmented stile inserts  800 . A complete stile assembly  500  has multiple segmented stile inserts  800  and end caps  900 . The stile assembly  500  may also have a tilt control lever  1000  or a control knob  1150  (FIGS.  11 A-B), as described below. Before or after frame assembly, the groove strip  700 , stile inserts  800  and geared end caps  900  are installed in the stile  600 . Advantageously, the end caps  900  are constructed of a material having some flexibility, such as a thin plastic, so that the end caps  900  can be deflected for louver removal and replacement. An end cap  900  has a gear  920  extending generally perpendicular to the end cap  900 . The gear  920  is press-fit through a corresponding insert aperture  810  and into a stile groove  610 . The gear  920  engages the toothed strip  700  so that linear movement of the strip  700  within the stile groove  610  rotates all of the end caps  900  and associated louvers  420  (FIG.  4 ). The strip  700  is slidably retained within a secondary stile groove  620 . An optional control lever  1000  inserts through a stile cutout  630  and attaches to the strip  700 , such as with glue, so that linear movement of the control lever  1000  causes linear movement of the groove strip  700  and a corresponding rotation of the end caps  900  and associated shutter louvers  420  (FIG.  4 ).  FIGS. 6A-B  illustrate a stile  600  having a full length groove  610 , a secondary groove  620  and a stile cutout  630 .  FIGS. 10A-C  illustrate a control lever  1000  having a back face  1001  that contacts the groove strip  700 , a front face  1002 , and a handle  1010  extending generally perpendicular to the front face  1002 . 
     FIGS. 7A-E  illustrate an elongated, generally planar toothed strip  700  having a toothed face  701  and an opposite smooth face  702 . A tongue  720  extends generally perpendicularly from the smooth face  702  and is configured to removably retain the strip  700  within the stile secondary groove  620  (FIGS.  6 A-B), as described with respect to  FIGS. 5A-B , above. In one embodiment, the toothed strip  700  extends a substantial portion of the stile groove  610  (FIGS.  6 A-B). In an alternative embodiment, the toothed strip  700  is segmented with interlocking ends, where each segment extends a fractional portion of the stile groove  610  (FIGS.  6 A-B). 
     FIGS. 8A-D  illustrate a segmented insert  800  having an outside face  801  and an inside face  802 . An aperture  810  is generally centered on the outside face  801  and extends to the inside face  802 . A collar  820  is disposed around the aperture  810  perimeter. and extends from the outside face  801 . Legs  830  extend generally perpendicular from the back face  802 . The aperture  810  accommodates an end cap gear  920  (FIGS.  9 A-B), which is inserted through the aperture  810  from the outside face  801 . The collar  820  provides spacing between the front face  801  and an end cap  900  (FIGS.  9 A-B). The legs  830  are spaced to fit within the stile groove  610  ( FIGS. 6A-B ) so that a shelf  840  rests on the stile  600  ( FIGS. 6A-B ) along the periphery of the groove  610  (FIGS.  6 A-B). 
     FIGS. 9A-B  illustrate a geared end cap  900  having a cap body  910 , side flaps  918 , end flaps  912  and a gear  920 . The cap body  910  is generally planar with an inside face  901  and an outside face  902 . The cap body  910  is adapted to cover the end of a louver  420  ( FIG. 4 ) so that the inside face  901  is proximate the louver  420  ( FIG. 4 ) and the outside face  902  is distal the louver  420  (FIG.  4 ). The side flaps  920  and end flaps  940  extend normal to the body  910  from the inside face  901  and are configured so that the side flaps  920  grip the faces of a louver  420  ( FIG. 4 ) and the end flaps  940  grip the edges of a louver  420  (FIG.  4 ). Accordingly, an end cap  900  is constructed of a material having some flexibility, such as a thin plastic, so that one or more of the side flaps  920  and end flaps  940  can be deflected for attachment to, or detachment from, a louver  420  (FIG.  4 ). In an alternative embodiment, not shown, the side flaps  920  or end flaps  940  or both are replaced by a wedge, prongs or similar structure extending from the center of the inside face  901  and adapted to insert into, and fixedly attached to, an end of a louver  420  (FIG.  4 ). The gear  920  is adapted to insert through a groove insert aperture  810  ( FIGS. 8A-B ) so that the gear teeth  922  engage the teeth of a groove strip  700  (FIGS.  7 A-E), a segmented slider  1200  ( FIGS. 12A-E ) or a stackable slider  1400  ( FIGS. 14A-D ) within a stile groove  610  (FIGS.  6 A-B). 
     FIGS. 11A-B  illustrate a stile assembly  1100  utilizing a toothed segmented slider  1200  and a tilt control knob  1150 . A complete stile assembly  1100  has multiple segmented inserts  800 , segmented sliders  1200  and end caps  900 . Alternatively, the stile assembly  1100  has a single stile insert and/or a single slider that extend a substantial portion of the stile groove  610  ( FIGS. 6A-B ) in lieu of segmented inserts  800  and/or segmented sliders  1200 , respectively. The end cap  900  gears engage teeth of the segmented sliders  1200  so that linear movement of the segmented sliders  1200  rotates the end caps  900  and tilts attached louvers accordingly, as described in detail with respect to  FIGS. 12A-E , below. The tilt control knob  1150  has a toothed gear  1154  extending generally perpendicular to a knob handle  1152  that engages teeth of a driven segmented slider. The driven slider pushes against an adjacent slider causing linear movement of all sliders  1200  in a chosen direction so as to tilt the shutter louvers  420  (FIG.  4 ). The tilt control knob gear  1154  is press-fit through an aperture  1162  of a cutout bracket  1160 , retaining the control knob  1150 . The cutout bracket  1160  is fixedly installed within a stile cutout  1140  on a face of the stile  1110 . In an alternative embodiment, a tilt control lever  1000  ( FIGS. 10A-C ) is installed in the stile cutout  1140  and is fixedly attached to one side of a slider  1200 . In this manner, linear movement of the control lever L 100  ( FIGS. 10A-C ) tilts the shutter louvers  420  ( FIG. 4 ) in a manner similar to that described with respect to  FIGS. 5A-B , above. 
     FIGS. 12A-E  illustrate a toothed segmented slider  1200  having a generally U-shaped cross-section, an outside toothed face  1201  along the back that is adapted to engage a control knob gear  1154  (FIGS.  11 A-B), an inside toothed face  1202  along one side that is adapted to engage an end cap gear  920  (FIGS.  9 A-B), and smooth outside faces  1203  slidably retained by a stile groove  610  (FIGS.  6 A-B). The end cap gears  920  ( FIGS. 9A-B ) engage the teeth of the inside face  1202  so that linear movement of the segmented sliders  1200  rotate corresponding end caps  900  ( FIGS. 11  A-B) and tilt an attached louver accordingly. The tilt control knob  1150  ( FIG. 11B ) has a toothed gear  1154  ( FIG. 11B ) extending generally perpendicular to a knob handle  1152  ( FIG. 11B ) that engages the teeth of a slider outside face  1201  so that rotation of the knob  1150  drives the linear movement of a slider  1200 . 
     FIGS. 13A-B  illustrate a stile assembly  1300  utilizing a stackable slider  1400 . A complete stile assembly  1300  has multiple inserts  800 , stackable sliders  1400  and end caps  900 . Alternatively, the stile assembly  1300  has a single stile insert that extends a substantial portion of the stile groove  610  ( FIGS. 6A-B ) in lieu of segmented inserts  800 . Stackable sliders  1400  engage end caps  900  so that linear movement of the stackable sliders  1400  rotate the end caps  900  and tilt associated louvers  430  (FIG.  4 ), as described with respect to  FIGS. 14A-D , below. In one embodiment, shown, a control lever  1000  installed through a stile cutout  1140  linearly actuates the stackable sliders  1400 , providing tilt control. In another embodiment, a stackable slider  1400  engages a control knob gear for tilt control, in a manner similarly described with respect to  FIGS. 11A-B , above. In yet another embodiment, an electric motor is mounted, for example, proximate a bottom spreader  410  ( FIG. 4 ) and has a lever attached to any of the tilt control mechanisms described above so as to provide powered and/or remote control louver tilting. 
     FIGS. 14A-D  illustrate a stackable slider  1400  having a body  1410  with a generally U-shaped cross section, a first tab end  1420  and an opposite second tab end  1430 . The body  1410  has a slotted back face  1412 , a toothed inside face  1414  and smooth outside faces. The stackable slider  1400  inside face  1414  is adapted to engage an end cap gear  920  ( FIGS. 9A-B ) so as to rotate the end cap  900  ( FIGS. 9A-B ) with linear slider movement in a manner similar to that of the segmented slider  1200  (FIGS.  12 A-E), described above. The stackable slider  1400 , however, has an aperture  1432  through one tab end  1430  and a corresponding plug  1422  extending from an opposite tab end  1420  so as to attach to adjacent sliders  1400  for uniform linear movement. The slotted back face  1412  is configured to accept a button (not shown) on an end cap gear  920  (FIGS.  9 A-B), allowing it to stabilize the linear movement of the slider  1400 . In an alternative embodiment, a stackable slider  1400  has a toothed back face adapted to engage a control knob gear, similar to that described for the segmented slider  1200  (FIGS.  12 A-E), above. 
   Louver end-caps, with or without gears for rack and gear tilt control, advantageously allow a shutter frame to be pre-assembled without the louvers. That is, louvers may be installed in the louver end caps as a manufacturing step occurring after frame assembly. In one embodiment, a shutter frame is pre-assembled from stiles and spreaders as described above. In another embodiment, a shutter frame is carved from a single piece of material using, for example, a CNC mill. In this manner, the manufacture of a variety of frame shapes, such as a sunburst, can be entirely automated. 
   A removable louver and tilt control shutter has been disclosed in detail in connections with various embodiments. These embodiments are disclosed by way of examples only and are not to limit the scope of the claims that follow. One of ordinary skill in the art will appreciate many variations and modifications.

Summary:
A tilt control is adapted to rotate a louver between at least a partially open position and a partially closed position within a shutter frame. The tilt control comprises a stile adapted as a portion of the shutter frame and a gear rotatably retained within the stile. A rack slideably retained within the stile. The gear engages the rack so that linear movement of the rack causes a corresponding rotation of the gear. The louver removably connected to the gear so that rotation of the gear rotates the louver.