Patent Publication Number: US-6983784-B2

Title: Control system for a vertical vane covering for architectural openings

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   The present application is a continuation of U.S. application Ser. No. 09/996,638, filed 28 Nov. 2001 (&#39;638 application), now U.S. Pat. No. 6,408,924, which is a continuation of U.S. application Ser. No. 09/592,510, filed 12 Jun. 2000 (&#39;510 application), now abandoned, which is a continuation of U.S. application Ser. No. 08/915,793, filed 21 Aug. 1997 (&#39;793 application), now U.S. Pat. No. 6,116,322, which is a continuation-in-part of U.S. application Ser. No. 08/724,576, filed Sep. 30, 1996 (&#39;576 application), now U.S. Pat. No. 6,135,188, and which claims priority to U.S. provisional application No. 60/047,075, filed 19 May 1997 (&#39;075 application). Each of the &#39;638, &#39;510, &#39;793, &#39;075, and &#39;576 applications is hereby incorporated by reference as though fully disclosed herein. 

   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates generally to coverings for architectural openings such as doors, windows, and the like, and more particularly to a control system for a covering having a plurality of vertically suspended vanes linearly movable between extended and retracted positions, as well as pivotally movable between open and closed positions, to control visibility and the passage of light through the architectural opening. 
   2. Description of the Relevant Art 
   Covers for architectural openings such as doors, windows, and the like have been known in various forms for many years. One form of such covering is commonly referred to as a vertical vane covering wherein a control system suspends and is operable to selectively manipulate a plurality of vertically suspended vanes such that the vanes can be linearly moved laterally across the architectural opening to extend or retract the covering and can be pivoted about longitudinal vertical axes to open and close the vanes. 
   Control systems for operating vertical vane coverings typically include a headrail in which a plurality of carriers associated with each vane are mounted for lateral movement, and include internal mechanisms for pivoting the vanes about their vertical axes. The headrails vary in construction and configuration to house the various types of carriers, but typically the headrails are relatively large and rectangular in cross section to enclose the working components of the system. Many such headrails have a slot along a bottom wall through which a portion of each carrier protrudes for connection to an associated vane. 
   Most control systems include pull cords that are operably connected to the carriers to shift or linearly move the carriers horizontally along the headrail and across the architectural opening. Control systems also usually include a horizontally disposed tilt rod operably connected to each carrier such that rotational movement of the tilt rod about its longitudinal axis transfers corresponding movement to the carriers and subsequently to the vanes to effect pivotal movement of the vanes about their longitudinal vertical axes. The tilt rod is typically rotated by a pull cord or a tilt wand that can be grasped by an operator of the system. 
   Considerable attention has been given to the configuration and construction of headrails as they are readily visible in vertical vane coverings. U.S. Pat. No. 4,361,179 issued to Benthin, for example, discloses a headrail having an opening through the top thereof so as to improve the aesthetics of the headrail. The primary components of each carrier in the system are confined within the interior of the headrail and generally “C” shaped hangers associated with each carrier circumscribe the headrail so as to be in a position to support an associated vane from beneath the headrail. 
   Carriers in vertical vane coverings may be interconnected by a pantograph so that movement of an endmost or lead carrier causes all of the carriers to move correspondingly. One problem with prior art control systems has been the manner in which the carriers are connected to the pantograph. Typically, due to the central connection system and expansion of the pantograph upon movement of the lead carrier, the other carriers are caused to skew slightly resulting in increased friction and making them more difficult to move along the length of the tilt rod. 
   Another shortcoming in prior art systems which utilize pull cords to move the lead carrier is the fact that the pulleys for returning and deflecting the pull cords are normally relatively small in size thereby requiring multiple revolutions to allow significant movement of the carriers which increases system friction and imposes unnecessary wear on the system. 
   Another problem with prior art control systems resides in the fact that they are difficult to assemble inasmuch as the drive mechanism of the carriers associated with the vanes must be uniformly aligned and operably connected to the tilt rod so that pivotal movement of the tilt rod moves the vanes between associated and corresponding angular positions. Accordingly, if the carriers are not mounted on the tilt rod uniformly, the vanes will not be properly aligned and uniformly angularly related to the architectural opening. As will be appreciated, in order to properly align and uniformly angularly relate the vanes to the architectural opening, the carriers have to be carefully and uniformly mounted on the tilt rod, which can be a time consuming endeavor. 
   Still another prevailing problem with prior art control systems for vertical vane coverings resides in the fact that the vanes are suspended in spaced relationship from the bottom of the headrail thereby establishing a gap that allows undesired light to pass between the top edge of the vanes and the bottom of the headrail. While the window covering itself may adequately block the passage of light through the architectural opening, this spaced relationship of the top edge of the vanes with the headrail undesirably permits the passage of light through the gap. 
   Since the pull cords utilized to move the lead carrier along the length of a tilt rod apply a significant force to the lead carrier which, in turn, expands or contracts the pantograph to effect corresponding movement of the other carriers, it will be appreciated that a skewing of the lead carrier can also be a problem depending upon the spacing of the pull cords from the tilt rod on which the carriers are mounted. Skewing of the lead carrier which increases drag on the system has traditionally also been a problem in prior art systems. 
   As will be appreciated from the above, drag in a control system resulting from friction between the various relatively movable parts has been a drawback. Accordingly, a need exists in the art for a low friction system that is easy to operate and is more durable for extended maintenance-free operation. 
   Another shortcoming in many prior art systems relates to the design of the headrail. The design and configuration of the headrail, as may not be readily appreciated, can create problems for an installer of vertical vane coverings. Many headrails used in vertical vane coverings are non-symmetric in transverse cross section in order to accommodate in a compact manner the working components of the associated control system. Examples of such headrails are disclosed in U.S. Pat. No. 5,249,617 issued to Durig, U.S. Pat. No. 4,381,029 issued to Ford, et al., and U.S. Pat. No. 4,381,029 issued to Ford, et al. While such systems may compactly accept the associated components of the control system, they are many times undesirable from an installation standpoint as they can only be installed in one orientation. If a headrail is blemished or marred, for example, on an outer visible surface, it is usually deemed unusable. 
   It is to overcome the aforenoted shortcomings in the prior art systems that the present invention has been developed. 
   SUMMARY OF THE INVENTION 
   The control system of the present invention is adapted for use in a covering for an architectural opening wherein the covering includes a plurality of vertically suspended vanes adapted to be uniformly disposed across the architectural opening or selectively retracted to one side of the opening. The control system is also adapted to selectively pivot the vanes about longitudinal vertical axes of the vanes so as to move the vanes between an open position wherein they extend perpendicularly to the architectural opening and in parallel relationship with each other, and a closed position wherein they lie parallel with the architectural opening and in substantially overlapping coplanar relationship with each other. 
   The control system has been uniquely designed for ease of assembly by an installer of the system and for ease of operation by a user. As in most vertical vane systems, the system of the present invention includes an elongated tilt rod that is confined within and supported by a headrail for rotative movement about its longitudinal axis. The tilt rod is operatively connected to a plurality of carriers disposed along its length, each of which suspends a separate vane, and wherein the carriers include a gear system driven by the tilt rod and adapted to selectively pivot the suspended vanes about their longitudinal axes. The tilt rod has a longitudinal groove adapted to cooperate with a mating projection on a gear within each carrier so as to facilitate uniform connection of the tilt rod with each carrier such that the vanes can be moved in unison between corresponding angles relative to the architectural opening for desired operation of the system. 
   The carriers are slidably mounted on the tilt rod for movement along the length of the tilt rod and are operably interconnected by a pantograph or scissors-type connector so that linear movement of any carrier along the tilt rod effects corresponding movement of the remaining carriers so that the vanes are, in turn, slidably moved across the window covering in unison. A pull cord system for selectively expanding or contracting the pantograph to correspondingly expand or retract the vanes across the architectural opening includes a traverse cord that is suspended along one side of the covering for operation, and is operably connected through a pulley system to a lead carrier for expansion and contraction of the pantograph and, thus, the covering. The lead carrier is a carrier at one end of the assemblage of carriers, and is the carrier that has full movement from one side of the architectural opening to the other as the covering is expanded or retracted by the traverse cord. The lead carrier, as well as the remaining standard carriers, has been uniquely designed so that the traverse cord is connected to the lead carrier in very close proximity to the tilt rod so as to minimize skewing of the lead carrier relative to the tilt rod upon pulling forces being applied to the lead carrier by the traverse cord. The traverse cord is preferably an elongated cord that is rendered endless by connection of the two ends of the cord to the lead carrier. 
   The tilt rod has been coated with a low friction material to further facilitate easy sliding movement of the carriers along the tilt rod. 
   Each standard carrier is uniquely designed to include a pocket or passage through which the traverse cord can freely extend. In one embodiment the pocket has a flexible side wall so that the cord can be inserted into the pocket by flexing the flexible side wall, but the flexible side wall is resilient and naturally returns to its original position to retain the cord within the pocket. This arrangement prevents drooping cords as has been a problem with conventional control systems. 
   Each carrier, with the exception of the lead carrier, has a pair of rollers adapted to ride on tracks provided internally along the length of the headrail so that the carriers move substantially friction free along the headrail. 
   Each carrier has a pair of engaged gears with one gear being a worm gear mounted on the tilt rod for unitary rotation therewith, and the second gear being a pinion gear associated with a hanger pin from which a vane is suspended. The carriers have been designed so that the pantograph interconnection with the carriers is centered over the tilt rod so as to minimize skewing of the carriers on the tilt rod upon expansion and contraction of the pantograph. 
   Each hanger pin has a pair of depending legs adapted to capture a vane therebetween. The vane is provided with an opening near its upper edge and one leg of the hanger pin has a hook that is removably received within the aperture so that the vane is suspended from one leg of the hanger pin. The hanger pin itself is uniquely designed so that the leg which bears the weight of the vane is relatively large in comparison to the other confining leg in contrast to conventional systems. The confining leg, which does not have a weight bearing function but merely captures the vane to prevent inadvertent release, is relatively thin and the overall weight of the pin has accordingly been reduced. The reduction in weight of the pin, however, has been obtained while obtaining an increase in strength by desirably distributing the weight of the pin onto the weight bearing leg. 
   The headrail for the control system has been uniquely designed so as to be transversely symmetric so that it can be installed in either direction without affecting the appearance or operation of the system. The headrail has a longitudinal slot along a bottom wall, and retention grooves along either side thereof to support and retain a light blocking rail, which extends downwardly from the headrail in close proximity to the top edge of the suspended vanes so as to substantially block the passage of light between the bottom of the headrail and the top of the vanes. 
   The pulleys used in the pull cord system have a diameter that is large relative to pulleys used in conventional systems, which not only improves the durability of the pulleys as they do not rotate through as many revolutions during operation of the covering, but in addition make the covering easier to operate, which is desirable from the user&#39;s standpoint. 
   Other aspects, features, and details of the present invention can be more completely understood by reference to the following detailed description of a preferred embodiment, taken in conjunction with the drawings, and from the appended claims. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a fragmentary isometric view looking down on the control system of the present invention in use in connection with a covering for an architectural opening. 
       FIG. 2  is a fragmentary isometric view similar to  FIG. 1  looking upwardly at the control system. 
       FIG. 3  is an exploded fragmentary isometric view illustrating the internal operational components of the control system with the carriers having been eliminated. 
       FIG. 4  is an isometric view looking down on elements of the control system without the headrail and illustrating the connection of the pantograph to a plurality of carriers, and with the pantograph in a retracted position. 
       FIG. 5  is an isometric view looking down on the pantograph and interconnected carriers with the pantograph in an expanded position, and with the tilt rod shown in dashed lines. 
       FIG. 6  is an isometric view showing the connection of the pantograph with a single carrier. 
       FIG. 7  is an enlarged exploded isometric view showing the connection of the pantograph with a single carrier. 
       FIG. 8  is an enlarged section taken along line  8 — 8  of  FIG. 2 . 
       FIG. 9  is an enlarged fragmentary section taken along line  9 — 9  of  FIG. 2 . 
       FIG. 10  is an enlarged section taken along line  10 — 10  of  FIG. 2  with a suspended vane shown in dashed lines and illustrating light-blocking rails mounted on the headrail. 
       FIG. 10A  is a fragmentary isometric view of one form of blocking profile that is attachable to the headrail to block the passage of light between the headrail and the suspended vanes. 
       FIG. 11  is an operational view similar to  FIG. 10  showing the mounting of the headrail to a supporting beam. 
       FIG. 12  is an isometric view of a mounting bracket used to secure the headrail to a supporting beam. 
       FIG. 13  is a vertical section through a hanger pin showing the operatively engaged worm gear on the tilt rod shown in dashed lines. 
       FIG. 14  is an isometric view showing an alternative lead carrier for the system of the present invention. 
       FIG. 15  is a fragmentary isometric view of the lead carrier of the primary embodiment and a standard carrier mounted on the tilt rod and showing the pull cords and pantograph operatively connected therewith. 
       FIG. 16  is a fragmentary isometric view showing one end of the control system and weighted tassels for operating the control cords. 
       FIG. 17  is a fragmentary isometric view showing an alternative weighted tassel with the core separated from the outer shell. 
       FIG. 18  is a diagrammatic section taken through a modified embodiment of the operating system of the present invention showing a standard carrier and an electric motor operatively connectable to the tilt rod to selectively pivot the carriers. 
       FIG. 19  is an exploded isometric view of the lead carrier in the primary embodiment showing the component parts of the lead carrier. 
       FIG. 20  is a bottom plan view of the preferred embodiment of the lead carrier. 
       FIG. 21  is an exploded isometric view of an alternative mounting plate and end cap at one end of the headrail looking down on the headrail. 
       FIG. 22  is an isometric view looking up from the bottom of the mounting plate shown in  FIG. 21 . 
       FIG. 23  is an enlarged end elevation showing the opposite side of the mounting plate as shown in  FIG. 22 . 
       FIG. 24  is an isometric view of the control system of the present invention illustrating an alternative embodiment using a bead chain for tilting the vanes. 
       FIG. 25  is an enlarged section taken through the headrail of  FIG. 24  illustrating an alternative embodiment of a carrier in the control system. 
       FIG. 26  is an isometric view of the alternative embodiment of the carrier with phantom line representations of the pantograph connected thereto and the traverse cord extending therethrough. 
       FIG. 27  is an enlarged top plan view of the carrier shown in  FIG. 26 . 
       FIG. 28  is a section taken along line  28 — 28  of  FIG. 27 . 
       FIG. 29  is an isometric view of an alternative embodiment of a tassel for use in connection to a bead chain used in the control system of the present invention. 
       FIG. 30  is an enlarged front elevation of the tassels shown in  FIG. 29 . 
       FIG. 31  is a vertical section taken through the tassel as shown in  FIG. 30 . 
       FIG. 32  is a view taken along line  32 — 32  of  FIG. 30 . 
       FIG. 33  is a section taken along line  33 — 33  of  FIG. 31 . 
       FIG. 34  is an isometric view of an alternative embodiment of the pantograph used in the control system of the present invention with phantom line representations of carriers connected thereto. 
       FIG. 35  is an isometric view looking up at the bottom of a male link in the pantograph of  FIG. 34 . 
       FIG. 36  is a bottom plan view of the male link shown in  FIG. 35 . 
       FIG. 37  is a section taken along line  37 — 37  of  FIG. 36 . 
       FIG. 38  is an isometric view of the bottom of the female link of the pantograph of  FIG. 34 . 
       FIG. 39  is an isometric view looking at the top of the female link of  FIG. 38 . 
       FIG. 40  is an enlarged top plan view of the female link of  FIG. 38 . 
       FIG. 41  is a longitudinal section taken along line  41 — 41  of  FIG. 40 . 
       FIG. 42  is an isometric view of a lock collar used to secure the tilt rod in the end cap at one end of the headrail. 
       FIG. 43  is an isometric view of the lock collar secured to the end of the tilt rod and with the end cap and a portion of the headrail shown in phantom lines. 
       FIG. 44  is an exploded fragmentary view of the lock collar of  FIG. 42  with an end of the tilt rod and a fastening screw shown in phantom lines. 
       FIG. 45  is an end elevation of the lock collar shown in  FIG. 42 . 
       FIG. 46  is a section taken along line  46 — 46  of  FIG. 45 . 
       FIG. 47  is an isometric view of an anchor plate for securing the ends of the traverse cord to the lead carrier in the control system of the present invention. 
       FIG. 48  is an isometric view looking up from the bottom of the top bracket used in conjunction with a conventional carrier to define the lead carrier and with the anchor plate being shown removed therefrom. 
       FIG. 48A  is an isometric view looking downwardly on the top bracket shown in  FIG. 48  and with a standard carrier shown removed from the top bracket and in phantom lines. 
       FIG. 49  is a bottom plan view of the anchor plate of  FIG. 47  with the top bracket of a lead carrier shown in phantom lines. 
       FIG. 50  is a section taken along line  50 — 50  of  FIG. 49 . 
       FIG. 51  is a fragmentary bottom plan view of a cord support system with the system in a nonsupporting position. 
       FIG. 52  is a fragmentary bottom plan view similar to  FIG. 51  with the support system in a supporting position. 
       FIG. 53  is an isometric view looking up from the bottom of the base component of the support system of  FIG. 51 . 
       FIG. 54  is an enlarged bottom plan view of the base shown in  FIG. 53 . 
       FIG. 55  is a section taken along line  55 — 55  of  FIG. 54 . 
       FIG. 56  is an isometric view looking downwardly on the support arm of the support system shown in  FIG. 51 . 
       FIG. 57  is a fragmentary isometric view looking at the bottom of the support arm shown in  FIG. 56 . 
       FIG. 57A  is an isometric view of the cord support system of  FIG. 51  looking downwardly and with the support system in a supporting position. 
       FIGS. 58A through 58C  are diagrammatic operational views showing the operation of the cord support of  FIG. 51 . 
       FIG. 59  is an isometric view of the cord support system of  FIG. 58  looking upwardly from the bottom and with the cord support system incorporated into the headrail of the control system of the present invention which is shown in phantom lines. 
       FIG. 60  is an isometric view of a cord tensioning system for the traverse cord of the control system of the present invention and with parts removed for clarity. 
       FIG. 61  is a section taken along line  61 — 61  of  FIG. 62 . 
       FIG. 62  is a fragmentary vertical section taken through the bracket and the anchor pin of the system shown in  FIG. 60  with the bracket mounted on a horizontal surface. 
       FIG. 63  is a vertical section similar to  FIG. 62  with the bracket mounted on a vertical surface. 
       FIG. 64  is a fragmentary isometric view looking downwardly on a system for removing the gap between segments of the traverse cord. 
       FIG. 65  is a fragmentary enlarged section taken along line  65 — 65  of  FIG. 64 . 
       FIG. 66  is an enlarged view taken along line  66 — 66  of  FIG. 65 . 
       FIG. 67  is an enlarged section taken along line  67 — 67  of  FIG. 65 . 
       FIG. 68  is an isometric view looking down from the top of an alternative bracket for supporting the headrail of the control system of the present invention from a supporting surface and with the headrail shown in phantom lines. 
       FIG. 69  is an isometric view looking up from the bottom of the bracket shown in  FIG. 68  with a support for the bracket being shown in phantom lines. 
       FIG. 70  is a bottom plan view of the bracket shown in  FIG. 69 . 
       FIG. 71  is an enlarged section taken along line  71 — 71  of  FIG. 70 . 
   

   DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The headrail  20  and other portions of the control system  22  of the present invention are shown in  FIGS. 1 and 2  with vertical covering segments, hereafter referred to as vanes  24  but which might assume other configurations, being suspended from carriers  26  in the system in adjacent side by side relationship. For purposes of clarity, the vanes are shown in dashed lines in  FIG. 2 . The headrail for the control system is designed to extend completely across the top of an architectural opening (not shown), and be suspended in a manner to be described hereafter from a beam or other supporting structure at the top of the architectural opening. While not being illustrated, the control system  22  is adapted to move the vanes  24  from a retracted position wherein the vanes are horizontally stacked adjacent one side of the architectural opening to an extended position wherein the vanes are evenly distributed across the architectural opening. In the extended position the vanes are adapted to be pivoted about longitudinal vertical axes between open positions wherein they extend perpendicularly to the architectural opening and in parallel spaced relationship to a closed position as illustrated in  FIGS. 1 and 2 , with the vanes overlapping and being substantially coplanar with each other. 
   The headrail  20 , as can be appreciated in  FIGS. 1 and 2 , is symmetric relative to a longitudinally extending vertical plane bisecting the headrail or, in other words, is symmetric in a transverse direction relative to the vertical plane. The headrail, as probably best seen in  FIG. 3 , has a main body  28  with arcuate downwardly convergent side walls  30  that are spaced at the top and bottom so as to define an open longitudinally extending slot  32  in the bottom and a longitudinally extending relatively broad groove  34  in the top. End caps  36  are securable with suitable fasteners  38  to each end of the main body for closure purposes. 
   The slot  32  in the bottom of the headrail  20  permits hanger pins  40 , forming part of the carriers  26  to protrude downwardly from the headrail and thereby suspend in a manner to be described later associated vanes  24  at a spaced distance beneath the headrail. Control cords forming part of an operating system also depend through the open slot at one end of the headrail as will be appreciated from the description that follows. 
   In addition to the headrail  20 , the control system  22  includes an elongated, horizontally extending tilt rod  42  ( FIG. 3 ) with a cord operated system for rotating the tilt rod about its longitudinal axis, a plurality of the aforenoted carriers  26  which are slidably mounted on the tilt rod and operatively associated therewith for pivoting the vanes about longitudinal vertical axes, and a pantograph  44  interconnecting the carriers such that movement of a lead carrier  26 L ( FIG. 15 ) along the length of the tilt rod by a pull cord mechanism causes each of the standard carriers  26 S to follow in desirably spaced relationship with each other. The pantograph, which forms part of an operating system with the pull cords and the tilt rod for manipulating the carriers, is probably best illustrated in  FIGS. 6 and 7 . 
   With reference to the exploded view in  FIG. 3 , the headrail  20  is illustrated with the end caps  36  having been removed from opposite ends thereof. Mounting plates  46  are securable to the end caps and are shown being properly positioned for supporting the operative components of the controls for pivoting the tilt rod  42  about its longitudinal axis, and for selectively expanding and retracting the pantograph  44 . More specifically, at the left end of the headrail a mounting plate  46 L is illustrated having a substantially cylindrically shaped bearing  48  with a cylindrical passage  50  therethrough. Adjacent to the cylindrical passage is a substantially “H” shaped slot  52  formed in a thickened section  54  of the mounting plate, with the slot  52  having a divider plate  56 . The mounting plate  46  in cross section is identically shaped to the end cap, and is securably mounted thereto with the screw-type fasteners  38  that pass through openings in the mounting plate and are threadedly received in channels  58  formed in the main body of the headrail. 
   A dual pulley  60  with independently movable individual pulley segments  62  and  64  (as best seen in  FIG. 3 ) is mounted in the H-shaped slot  52  in a vertical orientation and rotatably maintained in the slot by a pivot pin  66  that extends through the thickened section  54  on the mounting plate in which the H-shaped slot is formed to retain the dual pulley within the slot. The dual pulley, as will be described in more detail later, receives a traverse cord  68  used to move the carriers  26  along the length of the headrail. 
   The cylindrical passage  50  in the bearing  48  rotatably receives a barrel-shaped insert  70  ( FIG. 3 ) having a large diameter portion  72  and a smaller diameter portion  74 . The insert is hollow defining a relatively small diameter opening  76  through the smaller diameter portion  74  and a larger diameter opening  78  in the large diameter portion  72  of the insert. The smaller diameter opening  76  is adapted to slidably receive, but substantially conform in configuration and dimension with, one end of the tilt rod  42  so as to receive and support the end of the tilt rod for unitary rotation therewith. The large diameter portion  72  of the barrel insert defines a drum around which a tilt cord  80  extends. The tilt cord is wrapped around the drum to prevent slippage and so that the opposite ends of the cord  80  ( FIG. 16 ), which depend from the drum, can be pulled to selectively rotate the drum about its longitudinal axis in either direction. The passage  50  through the cylindrical bearing  48  in the mounting plate  46 L has large and small diameter portions to mate with the barrel insert so that the barrel insert is prevented from sliding through the bearing by a shoulder  83  ( FIG. 3 ) on the barrel insert defined between the large and smaller diameter portions. The bearing on the mounting plate is slotted at  84  through the bottom so that both ends of the tilt cord  80  can hang therethrough. 
   An alternative form of the mounting plate is shown in  FIGS. 21 through 25  and identified  46 ′. In the mounting plate  46 ′, it can be seen to have an H-shaped slotted opening  85  to receive the dual pulley  60  in the same manner as described with the mounting plate  46 . Again, the dual pulley supports the traverse cord  68  which is adapted to move the carriers and thus the suspended vanes across the architectural opening. Adjacent to the H-shaped slotted opening, a cylindrical bearing  87  projects from one side of the plate to rotatably receive and support one end of the tilt rod  42 . The cylindrical bearing has an enlarged cylindrical cavity  89  coaxial therewith which opens on the opposite side of the mounting plate. The cylindrical cavity is adapted to rotatably support a bead wheel guide  91  which is keyed in any suitable manner to the end of the tilt rod for unitary rotation therewith. The bead wheel guide has a scalloped periphery defining a plurality of adjacent cups which are sized and adapted to releasably receive beads  93  of a conventional beaded chain  95 . The interaction of the beads with the cups in the periphery of the bead wheel guide allows longitudinal movement of the beaded chain to rotate the bead wheel guide and consequently rotate the tilt rod about its longitudinal axis to pivot the vanes about their longitudinal axes as will be described in more detail later. The mounting plate  46 ′ also has a pair of longitudinally extending fingers  97  on opposite sides adapted to be received in the end of longitudinal channels of the headrail to align the mounting plate with the end of the headrail. The mounting plate  46 ′ is secured to the headrail as with the mounting plate  46  by the screw-type fasteners  38  that pass through openings in the end cap and the mounting plate to secure the mounting plate in place. The end cap, of course, also confines the bead wheel guide  91  within the cylindrical cavity  89 .  FIGS. 24 and 25  show the headrail with the beaded chain  95  in the control system and with the beaded chain ( FIG. 24 ) hanging adjacent to the traverse cord at one end. 
   The opposite or right end of the headrail, as best seen in  FIG. 3 , similarly has a mounting plate  46 R with a cylindrical bearing  86  having a reduced diameter cylindrical protrusion  88 . The bearing  86  defines a cylindrical passage  90  therethrough adapted to rotatably receive the opposite end of the tilt rod  42  which is predominantly rigid but slightly flexible. A gusseted bracket  92  also projects inwardly from the mounting plate and has a horizontal slot  94  therein adapted to rotatably support a horizontal pulley  96  that rotates about a pivot pin  98  received in the bracket. Again, the mounting plate  46 R is secured to the associated end cap  36  with screw-type fasteners  38  that are inserted into and threadedly received in the channels  58  at the opposite end of the headrail. The horizontal pulley  96  receives the traverse cord  68  which is preferably an elongated cord that is effectively rendered endless by its connection to the lead carrier  26 L in a manner to be described later. Both the horizontal pulley  96  and the dual pulley  60  are of relatively large diameter (i.e. approximately 0.608 inches) in comparison to pulleys used in most conventional systems which has been found to make the system easier to operate and extends the life of the component parts. 
   As mentioned previously, there are a plurality of carriers  26  disposed along the length of the headrail and slidably mounted on the tilt rod  42  for pivotal movement of the vanes  24  suspended from the carriers. The carriers are uniform in construction with the exception of the lead carrier  26 L which is, in the preferred embodiment and as best seen in  FIGS. 9 ,  15 ,  19  and  20 , merely a modification of a standard carrier  26 S through the addition of a snap-on carrier plate  100 . The lead carrier will be described in more detail later. 
   Each carrier  26 , probably best seen in  FIG. 7 , includes a main body  102 , a hanger pin  40  having a pinion gear  104  on its uppermost end, a worm gear  106 , and a pair of roller wheels  108 . The main body is substantially hollow, having a pair of side walls  110 , a flat end wall  112 , a bottom wall  114 , and an arcuate opposite end wall  116  from which a gusseted extension  118  forms a lateral extension. A connector in the form of a pivot pin  120  is formed on the top of one side wall  110  to enable attachment of the carrier to the pantograph  44 . The gusseted bracket  118  and the flat end wall  112  each have stub shafts  122  formed thereon to rotatably receive an associated snap-on roller wheel  108 . Mounted on the distal end of the gusseted bracket and on the flat end wall are horizontal slides in the form of substantially flat extension plates or ledges  124  ( FIGS. 7 through 9 ) which cooperate with the associated roller wheels in guiding movement of the carrier along the headrail  20 , as will also be explained hereafter. 
   Aligned circular openings  126  are provided through the side walls  110  in a vertical plane with the pivot pin  120 , which are of a diameter substantially the same as the outside diameter of the tilt rod  42  so as to rotatably receive the tilt rod. The worm gear  106  is mounted on the tilt rod within the interior of the carrier and is keyed to the tilt rod with an inwardly directed generally V-shaped protrusion  128  ( FIGS. 7 through 9 ) that is received in a longitudinally extending V-shaped groove  130  in the tilt rod. The worm gear, therefore, rotates in unison with the tilt rod. 
   The hanger pin  40 , as best seen in  FIGS. 7 and 13 , is elongated and of generally cylindrical configuration defining the pinion gear  104  at its uppermost end, a central cylindrical body portion  132 , and a pair of spaced depending legs  134  and  136  which are adapted to support the uppermost end of an associated vane  24 . The hanger pin is pivotally mounted within the arcuate end wall  116  of the carrier body with a shoulder  138  at the lower end of the pinion gear being supported upon an inwardly directed rim ( FIG. 7 ) projecting inwardly from the inner cylindrical wall of the arcuate section. The depending legs, therefore, protrude from the bottom of the main body. 
   Looking specifically at  FIG. 13 , one leg  134  of each hanger pin  40 , which will be referred to herein as the supporting leg, has a hook shaped projection  142 , and the body of the support leg is relatively thick in comparison to the other leg  136 , which will be referred to as the confining leg. The confining leg  136  has a beaded lower end  144  so that a relatively thin channel  146  between the two legs opens downwardly to receive the uppermost edge of an associated vane  24  that has a transverse opening  148  ( FIG. 2 ) therethrough adapted to be received upon and supported by the hook-shaped projection on the support leg. The confining leg urges the vane toward the support leg so that it does not inadvertently become released from the hanger pin. It is important to note that the confining leg, not having a supportive role, has been made relatively thin in comparison to the supporting leg thereby reducing the material used in the hanger pin. This reduction in material has been achieved while increasing the thickness of the supporting leg in comparison to conventional hanger pins so as to obtain approximately a 28% increase in strength while reducing the overall weight and cost of the pin. The average thickness of the supporting leg in the preferred embodiment is in the range of 0.095 to 0.105 inches, while the thickness of the upper end of the confining leg is in the range of 0.075 to 0.085. 
   When the hanger pin  40  is disposed within the main body, the pinion gear  104  is meshed with the worm gear  106  so that rotational movement of the worm gear about its horizontal axis effects pivotal movement of the hanger pin about its vertical axis. The tilt rod  42 , which rotates the worm gear, thereby effects pivotal movement of the vane suspended from the hanger pin. 
   As mentioned previously, the pantograph  44  is a mechanism that operatively interconnects each carrier  26  so that movement of the lead carrier  26 L causes a corresponding movement of the standard or following carriers  26 S thereby uniformly distributing the vanes across the architectural opening or retracting the vanes adjacent to one side of the opening. The pantograph, as best seen in  FIGS. 4 through 7 , has a plurality of pivotally interconnected links  150  which are interconnected in a scissors-like manner. There are two sets of links  152 A and  152 B, with each set having a plurality of parallel links angularly related to the links of the other set. A link  152 A of one set is pivotally connected at a midpoint to an associated link  152 B of the other set, and the end of each link in a set is pivotally connected to the end of a link in the other set. One set of links  152 B has a plurality of apertures  154  provided therethrough and one aperture  154 A ( FIG. 7 ) is offset from the center and substantially equally spaced or centered between the midpoint and one end of the link. The offset aperture is adapted to pivotally receive and be retained on the pivot pin  120  mounted on one side wall  110  of a carrier so that the link pivots about the pivot pin upon expansion or retraction of the pantograph. It is important to note and appreciate that the pivot pin  120  is vertically aligned with the tilt rod  42 . In this manner, when the pantograph  44  is expanded or contracted causing the links to move longitudinally of the headrail  20 , the force applied to the carrier  26  by the pantograph is along the tilt rod so that the carrier is not torqued or otherwise pulled in a manner that might cause the carrier to skew relative to the tilt rod. This connection causes a smooth gliding movement of the carriers along the tilt rod. To further improve the sliding movement, the tilt rod is preferably coated with a low friction material such as polyester so that there is a reduced resistance to movement of the carrier along the tilt rod. 
   As probably best seen in  FIG. 8 , the gusseted extension  118  on each standard carrier  26 S is defined by an upper plate  156  and an intermediate plate  158  connected to the arcuate end wall  116  of the main body, as well as a vertical or distal end plate  160  interconnecting the distal ends of the upper and intermediate plates and protruding downwardly therefrom. The distal end plate  160  has one of the stub shafts  122  for the roller wheels  108  mounted on an outer face thereof and an inwardly projecting flexible horizontal finger  162  spaced downwardly from the intermediate plate  158 . The flexible finger has a fixed end and a free end with the free end being spaced slightly, i.e. a distance slightly less than the diameter of the traverse cord  68 , from the outer surface of the arcuate wall. It will be appreciated that a pocket or passage  164  is defined between the flexible finger  162 , the intermediate plate  158 , the outer surface of the arcuate end wall  116  and the distal end plate  160 , which pocket is adapted to slidably receive and confine the traverse cord used in moving the carriers along the length of the headrail. The flexible finger is resilient so as to permit the cord to be inserted through the gap between the finger and the arcuate end wall, but the finger is rigid enough to retain the cord within the pocket after having been flexed so that if slack were to ever form in the cord, the cords would not droop from the pocket. In other words, the pocket confines the cord so that it will not distractively droop, for example, through the slot  32  formed in the headrail where it would otherwise be undesirably visible. 
   In an alternative form of the carrier identified by the reference number  26 ′ and shown best in  FIGS. 26 through 28 , it will be seen that the carrier is identical to carrier  26  except that horizontal finger  162  of carrier  26  has been replaced with a downwardly angled finger  165  having a vertical lip  167  which underlies the tip of a horizontal finger  169  that projects away from the main body of the carrier. A small gap  171  is provided between the vertical lip  167  and the horizontal finger  169  through which the traverse cord  68  can be inserted. A reinforcing plate  173  interconnects the lower end of distal end plate  160 ′ with intermediate plate  158 ′ and cooperates with the intermediate plate, the angled finger and the horizontal finger in defining a pocket  175  which releasably confines the control cord to prevent it from drooping through the open bottom of the headrail. 
   With further reference to  FIG. 8 , it will be appreciated that the arcuate side walls  30  of the headrail  20  have inwardly directed substantially horizontal protrusions or tracks  166  formed near the vertical center of the headrail. The tracks are adapted to support the roller wheels  108  so that the carriers can roll along the length of the headrail when moved by the pantograph  44 . The horizontal extension ledge  124  on the distal end plate  160  of each carrier  26  is spaced beneath the overlying roller wheel so as to accommodate an associated track on the headrail. The carrier is, therefore, confined on the tracks for movement therealong by guide elements in the form of the roller wheels  108  and slides  124  which stabilize the carriers relative to the headrail. Either the carrier or the tracks can be coated with a low friction material to facilitate an easy sliding movement of the carriers with polyester being a suitable coating for this purpose. 
   In the primary embodiment of the present invention, the lead carrier  26 L is merely a modified standard carrier  26 S, as is probably best illustrated in  FIGS. 9 ,  15  and  19 . As is probably best seen in  FIG. 19 , the lead carrier  26 L comprises a standard carrier  26 S and the snap-on carrier plate or top bracket  100  which is releasably connected to the standard carrier. The top bracket  100  has a main body portion  170  defining a top plate  172 , a pair of depending side plates  174 , and a pair of depending intermediate plates  176 , which extend in parallel with the length of the headrail  20 . On one side of the main body portion, a generally U-shaped member  178  is formed which is slightly wider than the main body portion. On the horizontally extending legs  180  of the U-shaped member  178 , elongated ovular horizontally oriented slots  182  are provided to releasably receive the stub shafts  122  on which the roller wheels  108  are mounted for the standard carrier  26 S. In other words, on the lead carrier  26 L, the roller wheels are either removed or not fitted and the stub shafts are snapped into the slots  182  on the horizontal legs of the bracket, which are resilient enough to allow the insertion of the stub shafts. Along the bottom edge of the legs  180  and the bottom edge of the side plates  174  are slides in the form of lateral, flat, plate-like protrusions  184  which are adapted to overlie the tracks  166  while the horizontal ledge  124  on the standard carrier body underlies the track of the headrail. In this manner, the lead carrier is confined for sliding movement along the tracks similarly to the standard carriers and, again, a coating of polyester or the like on the tracks provides a desirable low friction surface to facilitate an easy sliding movement. 
   As probably best illustrated in  FIG. 9 , the space between a side plate  174  and an intermediate plate  176  on the main body portion  170  of the top bracket  100  of the lead carrier  26 L defines a downwardly opening channel  185  in which segments of the traverse cord  68  are aligned. The outermost segment  68 A of the traverse cord passes through this channel  185 , while the innermost segment  68 B of the cord is diverted so as to extend between the two intermediate plates  176  where that particular cord segment  68 B, which defines one end of the traverse cord, is secured to the lead carrier by a screw-type fastener  186  which is threaded from beneath into a boss  188  provided on the top plate. The outermost segment  68 A of the cord which passes through the channel  185  extends to the far end of the headrail where it passes around the horizontal pulley  96  and returns with the opposite end of the traverse cord  68  being secured to the lead carrier  26 L by the second one of two screws,  FIG. 20 , that is threaded from beneath into a second boss  188  on the top bracket. Accordingly, the traverse cord, which is an elongated cord, has two ends which are anchored to the lead carrier so that the cord forms or defines an endless loop secured to the lead carrier so that the lead carrier moves in unison with the cord. Of course, as mentioned previously, movement of the lead carrier causes a corresponding movement of the remaining standard, or follower, carriers  26 S due to their interconnection with the pantograph  44 . 
   The traverse cord loop extends at one end of the headrail around the horizontal pulley  96  and at the opposite end of the headrail, around the two halves of the vertical dual pulley  60 , and from the dual pulley hangs downwardly and passes around a free or dangling vertically oriented pulley  190  ( FIG. 16 ) within a weighted or spring-biased housing  192  ( FIGS. 1 and 16 ), which retains the cord in a taut condition. As will be appreciated, when one of the depending portions of the traverse cord is pulled, the lead carrier  26 L is caused to slide in a first longitudinal direction relative to the headrail  20 , while pulling movement of the opposite portion of the cord causes sliding movement in the opposite direction. Movement in one direction of the lead carrier, of course, extends the vanes across the architectural opening, while movement in the opposite direction retracts the vanes adjacent to one side of the opening. 
   Tilting or pivotal movement of the vanes  24  about their vertical axes is effected through rotational movement of the tilt rod  42 , as was mentioned previously, with this movement being caused by movement of the tilt cord  80 , which is wrapped around the barrel insert  70  at the control end of the headrail. While not required, in the disclosed embodiment the tilt cord has two ends which are suspended adjacent to each other and support a weighted tassel  194  ( FIGS. 1 and 16 ) so as to hold each cord in a vertical and taut condition. Pulling a tassel  194  at one end of the cord obviously pivots the tilt rod in one direction, while pulling the tassel at the opposite end of the cord rotates the tilt rod in the opposite direction. Through the intermeshing of the worm gear  106  and pinion gears  104  within each carrier  26 , the vanes suspended from the carriers are caused to rotate in one direction or the other in unison and in alignment with each other. 
   While the weighted tassels  194  could take on numerous configurations,  FIG. 16  shows a tassel being made of a relatively heavy material, such as zinc or Zomac alloy, having a longitudinal hole  196  therethrough which receives one end of the tilt cord  80  which can be knotted to prevent the tassel from slipping from the cord. In an alternative embodiment shown in  FIG. 17 , an interior core  198  of a relatively heavy material such as zinc, having an axial passage  200  therethrough to receive the tilt cord  80  can be utilized with the cord being knotted at one end to prevent release of the core and an outer shell  202  of possibly a more aesthetically attractive material being slidably received over the core. 
   A tassel  203  designed for suspension from the end of the beaded chain  95  is illustrated in  FIGS. 29 through 33  and again is desirably made of a relatively heavy material such as zinc or Zomac alloy. As will be appreciated, the tassel is shown in hexagonal cross-sectional configuration even though other configurations would also be appropriate. The tassel is elongated having an upper crown  205  of smaller tapered diameter relative to the lower main body  207 . There are three interconnected vertically aligned chambers with an upper small chamber  209  opening through the top and through one side  211  of the upper crown. The upper chamber overlaps the next adjacent lower vertically aligned intermediate chamber  213  that opens through the opposite side  215  of the upper crown. The overlap between the two chambers defines a passage  217  between the chambers that is large enough to accommodate the size of a bead in the beaded chain  95  to which the tassel is connected. The lower wall  219  of the intermediate chamber  213  is slotted with the slot  221  opening through the side of the tassel and with the wall  219  being of a thickness to fit between two adjacent beads in a beaded chain and with the slot being of a size to slidably receive the thin connector  223  between beads in a chain. The lowermost chamber  225  which lies beneath the slotted wall  219  receives the free end of the beaded chain with the slotted wall retaining the beaded chain to the tassel and with the beaded chain passing upwardly through the passage  217  between the upper and intermediate chambers and out the open top of the tassel. The side wall  215  of the upper chamber encourages the beaded chain to stay confined within the slot in the wall even though the chain can be manually removed so that the tassel can be attached to or removed from the beaded chain or adjusted in length as desired. 
   As mentioned previously, the headrail  20  is provided with a broad groove  34  along its upper surface, with the groove formed by a depressed plate portion  204  ( FIGS. 1 and 11 ) vertically spaced from overhanging ledges  206  on the top of the headrail. The space between the ledges  206  and the depressed plate portion  204  define pockets  208  adapted to cooperate with a mounting plate  210  ( FIGS. 11 and 12 ), which is securable to a beam  212  or other structural member above an architectural opening. The mounting plate, as best seen in  FIGS. 11 and 12 , has a flat plate-like main body  214  with openings  216  through a top plate  218  thereof adapted to receive screw-type fasteners  220  to secure the plate to the supporting beam. The plate has a generally U-shaped connector  222  on one side with notches  224  on the free ends of legs  226  of the connector and plate-like horizontal extensions  228  extending in the opposite direction. The horizontal extensions  228  overlie and are spaced from a hook-shaped projection  230  from the bottom of the top plate. The horizontal extensions are spaced above the hook-shaped projection  230  so as to define a pocket  232  adapted to receive one of the overhanging ledges  206  of the headrail, while the other overhanging ledge  206  is received in the notches  224  in the free ends of the legs  226  on the U-shaped connector. When connecting the headrail to the mounting plate, one overhanging ledge  206  is inserted into the notches on the U-shaped connector and the headrail is then pivoted, as shown in  FIG. 11 , until the overhanging ledges are horizontally aligned, with the second horizontal ledge being snapped into the pocket  232  between the hook-shaped projection  230  and the horizontal extensions  228 . The headrail can be removed from the mounting plate in a reverse procedure, with it being understood that the hook-shaped projection is flexible enough to be moved out of blocking alignment with the overhanging ledge. 
   The lower surface of the headrail  20 , as best seen in  FIG. 10 , defines two parallel ledges  234 . The innermost extent of each ledge has an inverted hook-shaped protrusion  236  which confronts an inwardly directed protrusion  238  from the associated arcuate side wall  30 . The two protrusions define a pocket therebetween. Each pocket is adapted to receive a portion of a light-blocking rail or gap-restricting profile  240 , which extends longitudinally of the headrail. The light blocking rail, as best seen in  FIG. 10A , has an inverted V-shaped channel  242  formed along one side, with laterally directed edges adapted to extend beneath the protrusions  236  and  238  on the headrail. The edges thereby support the light-blocking rail and incorporate it into the headrail so that an angled flange  243  which extends downwardly through the longitudinal slot  32  in the headrail at an acute angle to horizontal from the associated ledge  234  on the bottom plate substantially fills the gap between the bottom of the headrail and the top of the suspended vanes. The flange  243  thereby forms a light-blocking barrier to light which might pass beneath the headrail  20  but above the top edge of the vanes  24 . The angle of the light-blocking flange prevents damage to the vanes in the event they swing about their connection to the hanger pins, such as in air currents passing through the architectural opening, as the vanes would then engage the light blocking rail at a non-damaging angle. 
   The depending angled flange  243  is interconnected with a horizontal leg  244  of each light-blocking rail, which in turn has an upturned lip  246  on its innermost end. The horizontal inturned leg  244  need not be continuous along the length of the light-blocking bar so as to save material costs and to increase flexibility. The horizontal leg  244  functions as a tilt rod support which prevents the tilt rod from sagging beneath the headrail when the carriers are drawn to one side. When the carriers are distributed along the length of the tilt rod, they too assist in supporting the tilt rod through their support on the tracks  166 . 
   In an alternative embodiment of the invention, as shown schematically in  FIG. 18 , the headrail  20 A is enlarged vertically so as to define a pocket  248  above the depressed plate portion  204  in which an electric motor or motors  250  can be mounted and used to operate the traverse cord and/or tilt rod for automated operation of the control system. The manner in which the motor or motors would be connected to the tilt rod or to the cords would be within the skill of one in the art and, therefore, has not been described in detail. 
   As was mentioned previously, the lead carrier  26 L in the preferred embodiment is simply a standard carrier  26 S having been modified with the inclusion of a top bracket or carrier plate  100 . An alternative lead carrier  252  is shown in  FIG. 14 . The lead carrier  252  is a single unit comprised of a hollow main body  254  which pivotally supports a hanger pin  40  with a pinion gear  104  that is meshed with a worm gear  106  through which the tilt rod  42  extends and is keyed for unitary rotative movement. These portions of the lead carrier are the same as described in connection with lead carrier  26 L. The main body includes a channel  256  through which both segments of the traverse cord  68  enter and only the outer segment  68 A passes through for further extension around the horizontal pulley  96  at the end of the headrail. The inner segment  68 B of the traverse cord is secured in a central downwardly opening channel  258  of the lead carrier by a set screw  260  threaded into a boss  262  formed on the carrier main body, while the returning outer segment  68 A of the traverse cord enters the same downwardly opening channel  258  from the opposite direction, and is also secured in the channel by a set screw (not seen) that is threaded into a second boss  264  provided on the main body of the carrier. The main carrier body has two outwardly opening, horizontally disposed V-shaped brackets  266  having lower edges  268  that are adapted to slide along the tracks  166  of the headrail. The V-shaped brackets are elongated so as to cooperate with the elongated side walls  30  of the headrail in keeping the carriers from skewing relative to the tilt rod as the carrier is moved along the length of the headrail by the pantograph. Accordingly, the elongated V-shaped channels add still another system for assuring alignment of the carriers to facilitate free sliding movement for ease of operation of the system. 
   A second embodiment  270  of a pantograph for use in the present invention is illustrated in  FIGS. 34 through 41 . As will be appreciated, the pantograph includes male and female links  272  and  274  respectively which are pivotally interconnected with each other and with the female link being additionally pivotally connected with the protrusion  120 ′ on a carrier  26 ′. The female link  274  is best seen in  FIGS. 38 through 41  to include a first set of three openings  276  and a second pair of openings  278  positioned between adjacent openings  276  of the first set. The three openings in the first set are positioned at opposite ends of the link and at its longitudinal center. The link is thickened with bosses  280  at each opening  276 . The bosses project from the top surface of the link with the bottom surface being substantially flat. Within each boss, there is a frustoconical surface  282  that tapers inwardly for a purpose to be described later. Beyond the tapered surface is a relatively large cylindrical recess  284  which communicates with the frustoconical surface. Each of the openings  278  in the pair of openings is a mirror image of the other and includes a cylindrical passage  286  with a rectangular keyway  288  extending completely through the link. The keyways extend from the cylindrical passage toward the center of the link as best seen in  FIG. 40 . 
   The male link  272 , as best seen in  FIGS. 35 through 37 , has a relatively flat top surface and three downwardly projecting pins  290  which have semi-circular lips  292  projecting in opposite longitudinal directions. The semi-circular lips are separated by a slot  294  which allows the lips to flex inwardly toward each other for purposes of being releasably snap connected to a female link as will be described hereafter. When connecting a male link to a female link as shown in  FIG. 34 , the pins  290  on the male link are advanced against the frustoconical surface  282  of a desired opening in the female link and the frustoconical surface cams the lips of the pin toward each other until they pass through the reduced diameter of the frustoconical surface. Upon reaching the relatively large cylindrical recess  284  the lips expand thereby being pivotally captured within an opening  276  in the female link. The male and female links are thereby pivotally interconnected. The protrusion  120 ′ on the top of each carrier  26 ′ has a rectangular tab  296  ( FIG. 27 ) which is sized to fit through the keyway  288  of the circular openings  278  in the female member. Once the tab has been inserted through the keyway, the carrier is rotated slightly and is thereby releasably and pivotally locked to the associated female link. Due to the relationship of the female links to the carriers, once the system is mounted in the headrail the keyway will not become aligned with the tab and, therefore, the female links will not be accidentally released from the carriers. With the male and female links interconnected with each other and with the female links connected to the carriers as illustrated in  FIG. 34 , the entire pantograph with the connected carriers is desirably assembled for maintenance-free operation. 
   It has been found in relatively long coverings that the tilt rod  42  has enough flex that it will sometimes be released from the bearing  86  in the mounting plate  46 . To prevent the tilt rod from being released, a lock collar  298 , best seen in  FIGS. 42 through 46 , has been designed to be connected to the end of the tilt rod and rotatably seated within a cavity  300  in the large cylindrical portion of the bearing  86  previously described in connection with  FIG. 3 . The anchor collar  298  is a cylindrical member having a cylindrical passageway  302  of slightly larger diameter than the tilt rod extending therethrough. The cylindrical passageway has an axially extending threaded groove  304  which is alignable with the longitudinal V-shaped groove in the tilt rod  42  so that the groove  130  in the tilt rod and the threaded groove in the cylindrical passageway complement each other to define a cylindrical hole into which a threaded screw-type fastener  306  can be advanced. As is best seen in  FIGS. 42 and 45 , the center of the defined hole is substantially aligned with the edge of the cylindrical passageway  302  through the collar so that when the screw-type fastener is advanced into the defined hole, the head of the screw overlies the end of the collar whereby the screw is prevented from being pulled through the collar and the tilt rod, which is now self-threadedly engaged with the screw, is also prevented from being pulled out of the collar. In this manner, with the collar seated within the bearing  86 , the tilt rod cannot be released from the mounting plate even on relatively long headrails that incorporate relatively long tilt rods. 
   An alternative system for anchoring the ends of the pull cord to the lead carrier is illustrated in  FIGS. 47 through 50 . An anchor plate  308 , as best seen in  FIG. 47 , includes an elongated substantially rectangular base  310  having an enlarged square head  312  at one end with transverse serrations  314  formed therein and an upstanding cylindrical pin  316  at the opposite end. The enlarged square head has a circular hole  318  therethrough adapted to receive a screw-type threaded fastener  320 . As described previously in connection with  FIGS. 15 ,  19 , and  20 , the ends of the traverse cord  68  were secured to the lead carrier  26 L with a pair of screw-type fasteners with each of the fasteners pinching and end of the cord between the head of the screw-type fastener and the main body of the carrier. When utilizing the alternative arrangement, the carrier  26 ′ is joined to a top bracket  100 ′ that is similar to the top bracket  100  described previously. The top bracket  100 ′ has a single threaded hole  322  at the approximate location of the two holes in the bosses  188  of the previously described top bracket  100 . The screw-type fastener  320  shown in  FIGS. 48 and 50  is adapted to pass through the hole  318  in the relatively large square head of the anchor plate and be threadedly received in the single threaded hole  322 . The anchor plate is positioned such that the serrated head overlies both ends of the pull cord  68  and the upstanding cylindrical pin  316  is abutted against a wall  317  of the carrier, as best shown in  FIGS. 49 and 50 . In this manner, the anchor plate lies between two partitions on the lead carrier which prevent lateral displacement of the anchor plate while the cylindrical pin prevents longitudinal movement. Once the screw-type fastener  320  is advanced through the opening in the anchor plate and into the threaded hole  322  in the top bracket  100 ′, the serrated head pinches the ends of the traverse cord against a pair of teeth  324  formed on the top bracket  100 ′ thereby preventing cord displacement. In doing so, the rectangular base of the anchor plate  308  is bent or flexed as shown in  FIG. 50 , and is securely positioned so that the cord will not be released until the screw-type fastener is removed. The top bracket  100 ′ also has a pair of depending trigger pins  326  for a purpose to be defined hereafter. 
   It has been found on relatively long headrails that when the vanes and carriers  26 ′ are all positioned to one side of the headrail as when the covering in an open position, the traverse cord  68  will sometimes sag and be visible through the bottom of the headrail. While, as mentioned previously, the traverse cord is supported by each of the carriers, when the covering is in an open position, the carriers are all stacked adjacent one side of the headrail thereby leaving the cords unsupported along substantially the remaining length of the headrail.  FIGS. 51 through 59  illustrate a cord support  328  which is operative to support the cords along the length of the headrail when the carriers are retracted into an open or substantially open position, but which are rendered inoperative when the lead carrier passes thereby as the covering is being closed. 
   The cord support  328  includes two pieces, a base piece  330  and a pivot or support arm  332 . The base piece is anchorable at any selected location along the length of the headrail to one of the lips adjacent the slot  32  in the bottom of the headrail. The base piece includes four tabs with one set of two tabs  334  being longitudinally aligned along one side of the base and another set of two tabs  336  being slightly laterally offset but similarly longitudinally aligned so that a straight line gap is established between the first set of tabs and the second set. The lip of the headrail is positioned in the straight line gap and the base is thereby secured to the headrail at any selected location along the length of the headrail. The base has a depending pin  338  with an enlarged head and a slot therethrough so that the head can flex inwardly to allow the pivot arm  332  to be pivotally connected to the base. 
   The pivot arm  332  can be seen to have a relatively long and substantially straight shank  340  and an enlarged head  342  having a circular passage  344  therethrough adapted to pivotally receive the pin  338  on the base. The enlarged head  342  on the support arm also has a small projection or catch arm  346  extending angularly relative to the shank and defining a pocket in the enlarged head between the catch arm and the shank. The catch arm extends laterally a small distance beyond the side of the shank for a purpose to be described hereafter. The support arm  332  is adapted to swing through a 90 degree arc between a position extending perpendicularly to the base  330  and transversely of the headrail wherein it underlies the traverse cord  68  and supports the same and a second position extending parallel with the base and in longitudinal alignment with the headrail along one side of the slot in the bottom of the headrail. It will be appreciated particularly by reference to  FIGS. 54 and 56 , that the base has a depending elongated bead  348  of triangular cross-section extending transversely and aligned with the pivot pin  338 , while the top side of the support arm has complementing crisscrossing grooves  350  that are also of triangular cross-section. The bead  348  in the base and the grooves  350  in the support arm are adapted to be releasably matingly engaged when the support arm is in either its supporting position or its nonsupporting position, and there is enough give in the pivot pin relative to the support arm to allow the arm to be releasably retained in position by the mating engagement of the bead  348  with one or the other of the perpendicular grooves  350 . 
     FIGS. 58A through 58C  are diagrammatic operational views showing how the support arm  332  is operatively engaged by the lead carrier  26 L to move the support arm between the supporting and nonsupporting positions. In  FIG. 58A , the support arm is shown in its supporting position with the lead carrier passing thereby from right to left. The trigger pins  326  on the lead carrier engage the shank  340  of the support arm causing it to pivot in a clockwise direction, as shown in  FIG. 58B . After the carrier passes completely by the support arm, it is fully pivoted and releasably retained in its nonsupporting position of  FIG. 58C , until the carrier passes from left to right. When passing from left to right, which is not illustrated, one of the trigger pins  326  on the lead carrier passes along the side edge of the shank of the support arm until it engages the catch arm  346 , and upon engaging the catch arm pivots the support arm in a counterclockwise direction from its nonsupporting position of  FIG. 58C  to its supporting position of  FIG. 58A . The support arm is then again in position to support the pull cords when the carriers are not present at that location. 
   As mentioned previously, the pull or traverse cord  68  hangs in a loop from one end of the headrail with the cord in the first described embodiment passing around a pulley within a weighted housing  192  ( FIG. 1 ). The housing illustrated in  FIG. 1 , for example, is simply a pulley positioned within an outer shell that is preferably weighted to hold the pull cord in a vertical position but in some instances, it is desirable to tension the pull cord. A system  352  for tensioning the pull cord is shown in  FIGS. 60 through 63 , and can be seen to include an anchor bracket  354  that can be mounted on a horizontal or vertical surface and a housing  356  including a pulley  357  around which the pull cord extends, an anchor pin  358  and a coil spring  360  surrounding the anchor pin. The housing has a cavity  362  with a transverse shaft  364  that rotatably supports the pulley  357  as shown in  FIG. 60 , and an elongated cylindrical cavity  366  that confines the anchor pin and the coil spring which is axially positioned thereon. 
   The anchor pin  358  has an enlarged head  368  at its upper end and a hook  370  at the lower end. The housing  356  further includes a shoulder  371  that engages the lower end of the coil spring with the upper end of the coil spring engaging the enlarged head  368  so as to confine the coil spring within the housing. The hook  370  of the anchor pin projects downwardly beyond the lower end of the housing and is adapted to be pivotally connected to the anchor bracket  354 . 
   The anchor bracket  354  has a pair of spaced parallel side walls  372  and an end wall  374  connecting the side walls so as to define a cavity therebetween, a horizontal cross shaft  376  extends between the side walls and forms a pivot anchor for the hook of the anchor pin. As will be appreciated, the cavity between the side walls opens in two mutually perpendicular directions out of two ends  378  and  380  of the bracket so that the bracket can be mounted on a horizontal surface as shown in  FIG. 62  or a vertical surface as shown in  FIG. 63  with the anchor pin protruding out of the cavity through one of the open ends. It will be appreciated that in operation, the anchor pin can be extended down and hooked around the cross shaft  376  to releasably secure the housing to the bracket. The coil spring  360 , of course, biases the housing downwardly and toward the bracket placing a tension in the pull cord. 
   In recent years there has been increased emphasis on making pull cords less amenable to child mishaps which are caused when the cords hang loosely and are separated thereby defining a gap between the cords into which a child can insert a body part.  FIGS. 64 through 67  illustrate a system  382  for removing the gap between the cords which consists of utilizing a elongated wand  384  with frictionally retained end caps  386  and  388  at the top and bottom end respectively. The wand  384  includes longitudinally extending grooves  390  on diametrically opposite sides and the caps at opposite ends of the wand are adapted to confine the cord at the ends of the wand and encourage the cord to remain within the longitudinally extending grooves  390 . The cap  386  at the upper end of the wand is spaced only a small distance from the headrail of the window covering and has a large substantially cylindrical passage  392  therethrough adapted to frictionally receive the end of the wand. The top end cap further includes a pair of laterally displaced passages  394  of ovular cross-section through which the cord slidably passes with these slots being aligned with the longitudinal grooves  390  in the wand. The lower end cap  388  is similar to the upper end cap in shape and configuration but in addition includes a pulley  396  rotatably supported therein and around which the pull cord extends. Of course, the pulley  396  is aligned with the grooves in the wand as well as the ovular slots  398  in the lower end cap. The length of the looped pull cord depending from the headrail is predetermined to substantially conform with the length of the wand so that the cords are restrained within the grooves provided in the wand but can be gripped by an operator of the window covering and separated from the wand enough to allow the operator to pull the cord in either direction. 
   It will also be apparent that the cord tensioner illustrated in  FIGS. 60 through 63  could also be incorporated as the lower end cap for the wand with only slight modifications. 
   As an alternative to the bracket  210  described previously for mounting the headrail to an overlying beam or other structural member, a bracket  400  as shown in  FIGS. 68 through 71  can be used. The bracket is again adapted to be connected to and between the overhanging ledges  206  on the top of the headrail. As mentioned previously, the space between ledges  206  and the depressed plate portion  204  define pockets  208  adapted to cooperate with the mounting plate. The mounting plate  400  has a flat plate-like main body  402  with openings  404  therethrough adapted to receive screw-type fasteners  406  to secure the plate to the supporting beam or other structural member. The plate-like main body has a generally U-shaped connector  408  on one side with notches  410  on the free ends of legs  412  of the connector and transversely extending side walls  414  having notches  416  in the ends opposite the U-shaped connector. The notches  416  in the side walls are adapted to engage and receive one overhanging ledge  206 , while the notches  410  in the U-shaped connector are adapted to receive the opposite overhanging ledge  206  so that the bracket is releasably connectable to the ledges thereby supporting the headrail from the overlying support beam. 
   It will be appreciated from the above that a control system for a vertical vane covering for an architectural opening has been described in various embodiments which has a number of advantages over prior art systems. Due to the alignment of the connection of the pantograph  44  with each carrier  26  over the tilt rod  42 , skewing of the carriers is minimized. Similarly, the formation of pockets in each carrier to receive the traverse cords and position the cords closely adjacent to the tilt rod also minimizes skewing so that the carriers are enabled to move easily along the headrail and the tilt rod. A low friction coating of the tilt rod further enhances the easy sliding movement. 
   The longitudinal groove  130  in the tilt rod, which cooperates with the protrusion on the worm gear  106  in each carrier, facilitates an easy assembly of the system in that the relative positioning of the worm gear  106  and pinion gear  104  can be made on each carrier so that the vanes associated with each carrier are positioned uniformly angularly. With this uniform relationship, an insertion of the tilt rod through the worm gears in each carrier allows the vanes to be very easily mounted and angularly aligned upon assembly. 
   The light blocking rails  240  are also easily connected to the headrail  20  and positioned in an aesthetically attractive position to not only substantially block the passage of light between the headrail on the top edge of the vanes  24  but in a manner such that the vanes are not damaged should they swing about their connection to the hanger pins. 
   The relatively large pulleys  60  and  96  used on the traverse cord enable an easy operation of the system while minimizing wear and heat generation to extend the life of the system. Further, the headrail  20  itself is symmetric about a longitudinal vertical central plane so that it can be mounted in either direction. This not only makes the system easy to mount, but also facilitates hiding a marred or blemished side wall of a head rail thereby salvaging headrails that might not be usable in other systems. 
   Although the present invention has been described with a certain degree of particularity, it is understood that the present disclosure has been made by way of example, and changes in detail or structure may be made without departing from the spirit from the invention, as defined in the appended claims.