Patent Publication Number: US-11035171-B2

Title: Adjustable mounting system for window blinds and shades

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of Non-Provisional patent application Ser. No. 14/934,608, filed Nov. 6, 2015, entitled “Adjustable Mounting System for Window Blinds and Shades”, which claims priority to Canadian Patent Application No. 2,870,986, filed Nov. 6, 2014, the entirety of which are incorporated by reference as if fully set forth herein. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates to a window blinds and shades, and more particular to adjustable systems for mounting window blinds and shades within architectural openings. 
     BACKGROUND 
     Various blinds are known for selectively covering architectural openings. Many of these include rollers that are rotatably mounted, usually in a horizontal orientation, for instance between the inner walls of an architectural opening, such as a windows recess. To facilitate installation of the roller, an arrangement may be provided whereby a pair of brackets is mounted on opposite inner walls of the architectural opening. The roller is than fitted between the two brackets. 
     Roller blinds are a popular form of window covering. Roller blinds generally consist of an elongated roller tube upon which the blind is wound. The roller tube has opposite ends and is generally provided with a roller clutch at one end and a plug or idler at the other end. The roller clutch includes a mechanism to raise and lower the blind by engaging a cord or chain (herein sometimes called continuous cord loop). The roller blind is mounted to a window by means of mounting brackets which secure the roller blind to the wall immediately adjacent the window or to the window frame, as the case may be. For example, one mounting arrangement involves a pair of brackets mounted on opposing inner walls of the architectural opening. The mounting brackets generally include a mounting fixture for engaging and mounting the clutch and/or the idler, depending on which end of the roller blind is being supported. 
     Several ways of fitting a roller between brackets are possible. For example, the ends of the roller may be provided with co-axially extending end plugs with axial holes for receiving a tab-like projection from the brackets. Alternatively the ends of the roller may be provided with co-axially extending end plugs, the end plugs being provided with axially projecting tabs for insertion into an opening in a bracket. These and other installation procedures can be burdensome, requiring careful location and mounting of the brackets and other components, and needing mounting tools and fasteners. 
     While the combination of a roller blind and mounting brackets is a popular window covering system, there are drawbacks with the design. Firstly, mounting the roller blind to the window (or wall adjacent the window as the case may be) requires careful measurement to ensure that the roller blind and fascia are level. If the roller blind is not exactly level, then the blind will tend to “telescope” on the roller, i.e., roll up in a slanted configuration, as it is wound up and unwound. This is not only unsightly, but it can cause roller blind malfunction. In such cases the user must re-drill the brackets that hold the casing of the blind to make it more level. This is a time consuming and tedious operation involving careful measurements and trial and error. 
     Additionally, many offices and some residential homes have concrete walls as window frames. This makes it very difficult for consumers to install window blinds via traditional drilling and screws. A specialized drill and installation method must be utilized in order to properly install window blinds in concrete walls. 
     Other window covering systems includes a bottom rail extending parallel to the headrail, and some form of shade material which might be fabric or shade or blind material, interconnecting the headrail and bottom rail. The shade or blind material is movable with the bottom rail between spread and retracted positions relative to the headrail. For example, as the bottom rail is lowered or raised relative to the headrail, the fabric or other material is spread away from the headrail or retracted toward the headrail so it can be accumulated either adjacent to or within the headrail. Such mechanisms can include various control devices, such as pull cords that hang from one or both ends of the headrail. 
     For the foregoing reasons, there is a need for a mounting system for window blinds and shades, such as roller blinds, that does not require burdensome installation procedures or mounting tools. There is a need for a mounting system for window blinds and shades that does not require that requires no screws or nails to install, and that can be easily installed on wall or window frame materials such as concrete. There is a need for a mounting system that simplifies leveling a window blind or shade during installation. Further, there is a need for a mounting system that provides safe, secure support for window blinds and shades. 
     SUMMARY 
     The embodiments described herein include a mounting system for a roller blind including a roller tube with a windows covering rolled around the tube, and a clutch mechanism for raising and lowering the window covering. The mounting system includes a tension bar, which provides a long and short adjustment of mounting system width for mounting under pressure between first and second sides of an architectural opening, such as a windows frame, to hold up the roller blind. The tension bar extends through a hollow roller tube of the roller blind, through a central recess in the clutch mechanism. Additionally, the tension bar may extend through an idler mechanism located at the opposite end of the roller tube from the clutch mechanism. 
     The length of the tension bar may be adjusted as a long adjustment. The mounting system also provides short adjustment of mounting width. Various mechanisms may be provided for short adjustment of mounting width, such as a latch mechanism, wedge mechanism, spring-loaded mechanism, or a turn-buckle system. 
     In one embodiment, a mounting system for a roller blind, the roller blind including a roller tube with a window covering rolled around the roller tube, and a mechanism associated with the roller tube for raising and lowering the window covering and including a first clutch and a continuous cord loop engaged by the first clutch, wherein the roller tube is hollow and the first clutch includes a central recess, comprises a first mounting fixture including a first end member mountable to a first side of a window frame; a second mounting fixture including a second end member mountable to a second side of a window frame; and a tension bar extending through the hollow roller tube and the central recess of the first clutch, and coupled to the first mounting fixture and to the second mounting fixture. 
     In another embodiment, a roller blind comprises a roller tube with a window covering rolled around the roller tube; a mechanism associated with the roller tube for raising and lowering the window covering including a clutch and a continuous cord loop having a loop end adjacent the clutch, wherein the roller tube is hollow and the clutch includes a central recess; a first mounting fixture including a first end member mountable to a first side of a window frame; a second mounting fixture including a second end member mountable to a second side of a window frame; and a tension bar extending through the hollow roller tube and the central recess of the first clutch, and coupled to the first mounting fixture and to the second mounting fixture. 
     In another embodiment, a window covering system comprises a headrail including a mechanism for extending and retracting a window covering; a clutch associated with the mechanism for extending and retracting the window covering, wherein the clutch includes a central recess; a tension bar extending through the headrail and the central recess of the clutch; a first mounting fixture including a first end member coupled to the tension bar for mounting under pressure to a first side of a window frame, wherein the first end member frictionally engages the first side of the window frame; a second mounting fixture including a second end member coupled to the tension bar for mounting under pressure to a second side of a window frame, wherein the second end member frictionally engages the second side of the window frame; and a mechanism associated with at least one of the first mounting fixture and the second mounting fixture for adjusting a width between the first end member and the second end member. 
     Additional features and advantages of an embodiment will be set forth in the description which follows, and in part will be apparent from the description. The objectives and other advantages of the invention will be realized and attained by the structure particularly pointed out in the exemplary embodiments in the written description and claims hereof as well as the appended drawings. 
     It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are intended to provide further explanation of the invention as claimed. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Non-limiting embodiments of the present disclosure are described by way of example with reference to the accompanying figures which are schematic and are not intended to be drawn to scale. Unless indicated as representing the background art, the figures represent aspects of the disclosure. 
         FIG. 1  is an perspective view of disassembled components, according to an embodiment. 
         FIG. 2  is a front side exterior perspective view of an adjustable blinds assembly, according to the embodiment of  FIG. 1 . 
         FIG. 3  is a back side perspective view of an adjustable blinds assembly with blinds housing removed, according to the embodiment of  FIG. 1 . 
         FIG. 4  is a perspective view of a tension bar assembly for an adjustable blinds assembly, according to the embodiment of  FIG. 1 . 
         FIG. 5  is a partial, somewhat schematic side view of a tension bar assembly for an adjustable blinds assembly, in open configuration, according to the embodiment of  FIG. 4 . 
         FIG. 6  is a partial, somewhat schematic side view of a tension bar assembly for an adjustable blinds assembly, in locked configuration, according to the embodiment of  FIG. 4 . 
         FIG. 7  is an side perspective view of a fixed width tension bar assembly, according to an embodiment. 
         FIG. 8  is an exploded view of a clutch assembly for an adjustable blinds assembly, according to an embodiment 
         FIG. 9  is a side sectional view of a clutch assembly for an adjustable blinds assembly, according to the embodiment of  FIG. 8 . 
         FIG. 10  is a side sectional view of a clutch assembly for an adjustable blinds assembly, according to the embodiment of  FIG. 8 . 
         FIG. 11  is a perspective view of a clutch assembly for an adjustable blinds assembly, according to the embodiment of  FIG. 8 . 
         FIG. 12  is a side sectional view of a detent assembly for an adjustable blinds assembly, according to an embodiment. 
         FIG. 13A  is a side sectional view of a first detail of a detent assembly for an adjustable blinds assembly, from the detail  13 A of  FIG. 12 . 
         FIG. 13B  is a side sectional view of a second detail of a detent assembly for an adjustable blinds assembly, from the detail  13 B of  FIG. 12 . 
         FIG. 14  is an exploded view of components at the clutch end of a detent assembly for an adjustable blinds assembly, according to the embodiment of  FIG. 12 . 
         FIG. 15  is an exploded view of components at the clutch end of an adjustable blinds assembly, according to an embodiment. 
         FIG. 16  is an interior end view of a dial adjustment assembly for short adjustment of an adjustable blinds assembly, according to the embodiment of  FIG. 15 . 
         FIG. 17  is a side sectional view of a dial adjustment assembly for short adjustment of an adjustable blinds assembly, according to the embodiment of  FIG. 15 . 
         FIG. 18  is a detail schematic of a radial slip clutch system of a dial adjustment assembly for short adjustment of an adjustable blinds assembly, according to the embodiment of  FIG. 16 . 
         FIG. 19  is a perspective view of a bushing-spring assembly from an adjustable blinds assembly, according to an embodiment. 
         FIG. 20  is a side sectional view of a bushing-spring assembly from an adjustable blinds assembly, according to the embodiment of  FIG. 19 . 
         FIG. 21  is a side sectional view of an adjustable blinds assembly with long adjustment mechanism, according to an embodiment. 
         FIG. 22  is a side sectional view of the clutch side of an adjustable blinds assembly with short adjustment mechanism, according to an embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     The present disclosure is here described in detail with reference to embodiments illustrated in the drawings, which form a part here. Other embodiments may be used and/or other changes may be made without departing from the spirit or scope of the present disclosure. The illustrative embodiments described in the detailed description are not meant to be limiting of the subject matter presented here. Furthermore, the various components and embodiments described herein may be combined to form additional embodiments not expressly described, without departing from the spirit or scope of the invention. 
     Reference will now be made to the exemplary embodiments illustrated in the drawings, and specific language will be used here to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended. Alterations and further modifications of the inventive features illustrated here, and additional applications of the principles of the inventions as illustrated here, which would occur to one skilled in the relevant art and having possession of this disclosure, are to be considered within the scope of the invention. 
     The present disclosure describes various embodiments of a roll-up window covering (or roller blind) system. As used in the present disclosure, a roller blind system is a system for raising and lowering a window covering including an elongated roller tube upon which the blind is wound. In the present disclosure, “window covering” includes any covering material or fabric that may be lowered or spread to cover a window or other architectural opening using a roller blind system. Window covering embodiments described herein will refer to fabric, blind or blinds, it being understood that these embodiments are illustrative of other forms of window coverings. 
     In another embodiment, the tension bar may extend through a headrail of a window covering system, and through a central recess in a clutch mechanism that is part of a mechanism in the headrail for extending and retracting window coverings. In this embodiment, the tension bar does not extend through a hollow roller tube. 
     As used in the present application, the term “window frame” also encompasses other architectural openings such as archways, and the term “casement” is sometimes used herein in lieu of “window frame”. References to a “side” or to an “inner surface” of a “window frame” also encompass sides or inner surfaces of other architectural openings. 
     As used in the present disclosure, a “continuous cord loop” is an endless loop of flexible material, such as a rope, cord, beaded chain and ball chain Continuous cord loops in the form of loops of cord are available in various types and ranges of diameter including for example D-30 (1⅛″-1¼″), C-30 (1 3/16″-1 7/16″), D-40 (1 3/16″-1 7/16″), and K-35 (1¼″-1½″). Additionally, various types of beaded chain and ball chain are commonly used as continuous cord loops for roller blinds. 
     Roller blinds are generally controlled by a roller clutch assembly that is used to raise and lower the blind, manually or under motor control. These clutch assemblies generally consist of a housing having a barrel portion to which a roller tube support structure is rotatably mounted. The blind is coupled to a roller tube which is in turn coupled to the roller tube support structure. A clutch assembly is rotatably mounted to the barrel portion of the housing and is coupled to the roller tube support member. A looped cord or chain is in turn coupled to the clutch assembly to permit the user to rotate the clutch (and thereby the roller tube) by pulling on the cord. This permits the user to raise and/or lower the blind by pulling on the cord to rotate the roller tube in the desired direction. 
     The present disclosure provides a mounting system for a roller blind, in which a mechanism for raising and lowering a window covering rolled around a roller tube includes a clutch. The roller tube is hollow and the clutch includes a central recess, i.e., the clutch includes a hollow center. A tension bar extends through the hollow roller tube and the central recess of the clutch. As the term “extends through” is used in the present disclosure, a tension bar extends through the hollow roller tube and the central recess of the clutch either by extending completely through these structures, or by extending partially through these structures. In an alternative embodiment, a tension bar extends through a headrail and a central recess of a clutch associated with the headrail. 
     The mounting system includes a first mounting fixture with a first end member, and a second mounting fixture with a second end member, mountable respectively at first and second sides of a window frame. The tension bar is coupled to the first mounting fixture and the second mounting fixture. 
     In an embodiment, at least one of the first mounting fixture and second mounting fixture includes an adjustment mechanism for adjusting a width between the first and second end member. In an embodiment, the adjustment mechanism for adjusting a width between the first and second end member is a short adjustment mechanism for adjusting the width between the first and second end member over a short distance. In an embodiment, adjustment of the width between the first and second end member over a short distance calibrates the width of the mounting system to the width of the window frame, and adjusts the pressure exerted by the first end member and the second end member to mount the roller blind using pressure mounting. 
     Various embodiments of short adjustment mechanism may be employed, including for example spring-loaded mechanisms in which the mounting system exerts a substantially constant pressure against the window frame, and arrangements in which the user adjusts the width of between the first and member and second end member, and calibrates the pressure exerted by first end member and second end member against the window frame. Exemplary short adjustment mechanisms include, without limitation, short adjustment through a spring-loaded mechanism, a latch mechanism, a wedge mechanism, a sprocket mechanism, or a turn-buckle mechanism. In some embodiments, the user effects the short adjustment mechanism without tools. The short adjustment mechanism may incorporate an adjustment dial that can be adjusted manually by a user, or a system such as a worm gear system that may be adjusted using a tool. In another embodiment of a short adjustment mechanism, an end pad mounted to an adjustment sprocket is screwed onto a threaded shaft, and is tightened by a user using a tool to rotate the sprocket. 
     In an embodiment, a short adjustment mechanism is located at a clutch side of the adjustable mounting system. In another embodiment, the short adjustment mechanism is located at an idler side of the adjustable mounting system. 
     In an embodiment, the mounting system incorporates a tension bar with a length that is adjustable over a significant length, sometimes herein referred to as a long adjustment mechanism. In an embodiment, the long adjustment mechanism includes a female tension bar and a male tension bar adjustably mounted within the female tension bar. In an embodiment, the long adjustment mechanism includes a mechanism for displacing the male tension bar relative to the female tension bar, and a mechanism for locking the male tension bar within the female tension bar. 
     In an embodiment of long adjustment mechanism, the female tension bar includes slots at a plurality of stop positions spaced along the female tension bar, and the male tension bar includes a compressible member that may expand within slots at one or more of the stop positions. In another embodiment, a male tension bar includes a pull rod mounted for displacement within the male tension bar, and a conical expander mechanism that expands to wedge against an inner wall of a female tension bar. In a further embodiment, a female tension bar includes a plurality of ridges defining detent positions spaced along an inner wall of the female tension bar. The male tension bar is a profiled push bar that supports ball bearings that engage the female tension bar in the detent positions, and that includes locked and unlocked configurations. 
     In an embodiment, the mounting system includes an end member such as an end pad for frictionally engaging the window frame, and for dampening the force of the mounting system against the window frame. 
     In various embodiments, a mounting system for a roller blind incorporates an adjustable length tension bar based upon any of the long adjustment mechanisms, in combination with any of the short adjustment mechanisms. In other embodiments, a mounting system for a roller blind incorporates a fixed length tension bar, in combination with any of the short adjustment mechanisms. 
     The disclosure further provides various embodiments of roller blinds incorporating the mounting systems described herein. 
     Various roller blinds adjustable mounting systems incorporating a long adjustment mechanism to adjust the length of a tension bar are described below with reference to the following embodiments: 
     (a) a lever assembly for long adjustment is illustrated at  FIG. 1-6 ; 
     (b) a detent assembly with button for long adjustment is illustrated at  FIGS. 12, 13A, 13B, 14, 19, and 20 ; 
     (c) a cone-expander for long adjustment is illustrated at  FIG. 21 . 
     Various roller blinds adjustable mounting systems incorporating a short adjustment mechanism to adjust over a short distance the width between end members coupled to a tension bar, are described below with reference to the following embodiments: 
     (a) a spring-loaded button assembly for short adjustment is illustrated at  FIGS. 8-11 ; 
     (b) a spur gear assembly with dial for short adjustment is illustrated at  FIGS. 15-18 ; 
     (c) a worm gear assembly for short adjustment is illustrated at  FIG. 22 . 
     In other embodiments, a roller blinds adjustable mounting system incorporates a fixed length tension bar, as illustrated in  FIG. 7 , wherein the fixed length tension bar may be deployed in combination with any of the short adjustment mechanisms. 
     The roller blinds mounting systems described below include examples of a particular long adjustment mechanism in combination with a particular short adjustment mechanism. The lever assembly for long adjustment of  FIG. 1-6  is described as usable in combination with the spring-loaded button assembly for short adjustment of  FIGS. 8-11 . The detent assembly with button for long adjustment of  FIGS. 12, 13A, 13B, 14, 19, and 20  is described as usable in combination with the a spur gear assembly with dial for short adjustment is illustrated at  FIGS. 15-18 . However it should be noted, advantageously, that various long adjustment mechanisms are interchangeable, and various short adjustment mechanisms are interchangeable. For example, the cone-expander long adjustment mechanism of  FIG. 21  may be easily interchanged with the lever assembly long adjustment mechanism of  FIGS. 1-6 . In another example, the spur gear assembly with dial for short adjustment of  FIGS. 15-18  may be easily interchanged with the worm gear assembly for short adjustment of  FIG. 22 . 
     Various long adjustment mechanisms disclosed herein incorporate external actuating implements; similarly various short adjustment mechanisms incorporate external actuating implements. In the present disclosure, an external actuating implement refers to an external component of the adjustable window blinds or shades that can be manipulated or otherwise operated by a user to actuate a long adjustment mechanism, or to actuate a short adjustment mechanism. Examples of external actuating implements for long adjustment mechanisms are the unlock handle  108  of lever assembly  115  ( FIG. 2 ), and the detent push button  220  of detent assembly  200 . Examples of external actuating implements for short adjustment mechanisms are the button  167  of locking pin  164  in the spring-loaded button assembly  150  ( FIGS. 9, 11 ), and the adjustment dial  238  of spur gear assembly with dial  225 . In various embodiments, the external actuating mechanism may be manipulated by a user without requiring tools. In an alternative embodiment, such as the worm gear  350  of the worm gear assembly for short adjustment of  FIG. 22 , an external actuating mechanism be manipulated by a user using a tool  360 . 
       FIGS. 1-6  show an adjustable-length tension bar assembly of an adjustable and portable blind assembly  100 , which permits easy installation on various window frame sizes without any tooling. Adjustable length blind assembly  100  incorporates an internal adjustable tension bar to accommodate a range of window sizes.  FIG. 1  is a perspective view of disassembled components of an adjustable blind assembly, including a male tension bar  116  and a female tension bar  118 . In the fully assembled adjustable blinds assembly  100 , the male tension bar  116  and a female tension bar  118  are secured together at a selected length, and extend through male fabric tube  110  and female fabric tube  112 . A clicker  122  is located at the male tension bar  116 . Components at a clutch end of the adjustable length blind assembly include a clutch assembly  150  engaged by a chain or continuous cord loop  128 . The other, idler, end of the blind assembly includes an idler  104 , retaining ring  120 , and an unlock handle  108 . At both ends of adjustable length blind assembly  100 , end plates  102  and rubber end pads  106  serve as mounting structures for mounting assembly  100  to a window frame under pressure. Other components include a male fabric tube  110  and female fabric tube  112  coupled in an adjustable length telescoping structure. In an embodiment, male fabric tube  110  and female fabric tube  112  respectively support first and second blinds fabrics (not shown). Male blind housing  124  and female blind housing  126  provide an adjustable-length housing for blind assembly  100 , and support other components of adjustable blinds assembly  100  during installation. 
       FIG. 2  is a front side exterior perspective view of the adjustable blinds assembly  100 , including adjustably coupled female blinds housing  126  and male blinds housing  124 . The detail view of the end of female blinds housing  126  includes unlock handle  108  and left end plate  101 . Unlock handle is shown in a raised, locked position. The detail view of the end of male blinds housing  124  includes chain  128  and right end plate  102 .  FIG. 3  is a back side perspective view of the adjustable blinds assembly  100  with blinds housing removed. The center detail shows the adjustable length telescoping structure of male fabric tube  110  and female fabric tube  112 . At the end of the male fabric tube, the unlock handle  108  is shown in a lowered, unlocked position. 
       FIG. 4  is a perspective view of an adjustable length tension bar assembly, or lever assembly,  115 . Lever assembly  115  includes a male tension bar  116  and a slotted female tension bar  118 . A clicker  122  with outwardly biased ears  122   a,    122   b  is attached to one end of the male tension bar. A lever (unlock handle  108 ) is attached at the other end of the male tension bar, and controls the configuration of the adjustable length tension bar assembly  115 . When fully assembled, the female tension bar  118  is fixed and the male tension bar  116  is mounted to slide, and rotate, within the female tension bar. As the unlock handle  108  is rotated, the clicker  122  rotates with the male tension bar  116 . In one configuration, the ears  122   a,    122   b  of clicker  122  compress against the inner wall of the female tension bar  118 , permitting the male tension bar to slide within the female tension bar. In the other configuration, the ears  122   a,    122   b  of clicker  122  decompress when released within one of the slots of female tension bar  118 . 
     Internal adjustable tension bar assembly  115  has two configurations, open and locked, depending on the position of unlock handle  108  (cf.  FIGS. 2, 3 ). The tension bar assembly  115  is open when the clicker  122  is compressed. This configuration allows the male tension bar  116  and the female tension bar to slide freely, extending or contracting the length of the adjustable blinds. This open configuration is shown schematically in  FIG. 5 . In contrast, when the unlock handle is rotated to the locked position (e.g., 90 degrees), the clicker  122  decompresses at one of the sets of slots of female tension bar  118 . In one embodiment, when in this locked configuration, the tension bar can be extended but cannot be contracted. This locked configuration is shown in  FIG. 6 . 
       FIG. 7  illustrates a fixed-length tension bar assembly  140 . Fixed length tension bar assembly  140  includes a fixed length tension bar  142 , such as an extruded bar. A clutch assembly  148  is located at a clutch end of the tension bar. The clutch assembly  148  includes a central recess (not shown) and the fixed length tension bar extends through the central recess. An idler  144  and idler end plate  146  is located at the other end of fixed length tension bar  142 . In an embodiment, fixed length blinds incorporating fixed-length tension bar assemblies may be provided in various fixed sizes, which may be selected to fit specific window frame standards. As compared with the adjustable length tension bar assembly of  FIGS. 1-6 , the fixed-length tension bar assembly  140  of  FIG. 7  does not require a telescoping housing or other window blinds structures such as adjustable width bottom bars (at the bottom of the blinds fabric); two sets of fabric; or internal adjustable tension rods with control mechanism. Hence, fixed length tension bar assemblies are amenable to lower cost manufacture. A fixed length tension bar assembly may include a short adjustment mechanism to facilitate mounting to a windows frame or casement. For example, the clutch assembly  148  may be based upon the short adjustment clutch assembly  150  of  FIGS. 8-11 . 
       FIGS. 8-11  show a clutch assembly, also herein called spring-loaded button assembly, for an adjustable blind assembly, incorporating a clutch assembly with a spring-loaded mechanism for short adjustment of mounting to a window frame. As seen in the exploded view of  FIG. 8 , the clutch assembly  150  serves two functions. Clutch assembly  150 , including clutch  168  and clutch rotor  162 , allows the fabric tubes of the blinds (not shown) to rotate freely while pulling on chain  170 , while preventing rotation of the fabric tubes in other circumstances, as is conventional. Secondly, the clutch assembly incorporates a spring loaded short adjustment mechanism, which applies a continuous load to the window frame following a push of a button. Clutch assembly  150 , including clutch  168  and clutch rotor  162 , include a central recess, and a tension bar (not shown) extends through the central recess and is coupled to clutch and spring release body  152  as subassemblies of an adjustable-width mounting assembly for a roller blind. Roller blind clutches of this type are supplied, for example, by Ciera Industries, Inc. of Valencia Calif. 
     Key components in the spring loaded mechanism include a clutch and spring release body  152 , compression spring  158 , locking pin  164 , launch pin  154 , and locking pin compression spring  166 . The clutch assembly  150  has two modes of operation: closed and extended. To close the spring loaded assembly, as shown in  FIG. 9 , the end plate  160  and the launch pin  154  are pushed into the clutch and spring release body  152 . Enough force must be applied to overcome the compression spring  158 . When the end plate  160  and the launch pin  154  are pushed into the clutch and spring release body  152 , the locking pin  164  is free to push upwards under the force of locking pin compression springs  166 . A profiled aperture  165  of the locking pin  164  engages the launch pin  154 , locking the clutch assembly  150  in closed configuration. 
     The locking pin  164  terminates at a button  167  ( FIG. 11 ). To extend the clutch assembly  150 , the user presses the locking pin  164  into the clutch and spring release body  152  via button  165 . The movement of locking pin  164  disengages the launch pin  154 , allowing the compression spring  158  to decompress. The potential energy stored in compression spring  158  is released, forcing the launch pin  154  and the end plate  160  out of the clutch and spring release body  152 . In this locked configuration, the adjustable blind assembly is fully extended to the width of a window frame. 
     In an embodiment, while in the locked configuration the clutch assembly  150  applies sufficient force to the window frame to hold up the entire adjustable blind assembly. In an embodiment, the clutch assembly  150  applies approximately 40 pounds of force to the window frame when in the locked configuration through metal end cap  160  and rubber end pad  156  ( FIG. 11 ). Rubber end pad  156  provides friction and absorbs excess pressure when engaging a window frame or casement. 
     The adjustable blind assembly of  FIGS. 8-11  uses a tension bar as a load-bearing bar in conjunction with to load applied to a window frame by the clutch assembly  150 . The tension bar assembly coupled to the clutch assembly  150  may have a fix width, such as the tension bar assembly  140  of  FIG. 7 . Alternatively the tension bar assembly coupled to assembly  150  may allow a long adjustment of width, such as the adjustable tension bar  115  of  FIGS. 1-6 . 
     In an example, a user installed an adjustable length blind assembly  100  incorporating the long-adjustable tension bar  115  of  FIGS. 1-6  and the short-adjustable clutch assembly  150  of  FIGS. 8-11 . The user compressed the clutch assembly  150  so that it was in its closed position, pushing the end plate  160  against the clutch body  152 . The user placed the unlock handle  108  in its locked position, then extended the housing of adjustable length blind assembly  100  to a length approximately corresponding to the width of the windows frame targeted for installation. The user then positioned the adjustable length blind assembly  100  within the windows casement at the intended mounting location, and pushed the release button to extend the clutch assembly. 
     To uninstall the adjustable length blind assembly  100 , a user pulled the unlock handle  108  to its open position, disengaging internal tension bar  115  ( FIG. 3 ). Two persons may support the adjustable length blind assembly  100  to prevent it from falling, before disengaging the internal tension bar  115 . 
       FIG. 12  is a side sectional view of a detent assembly  200 , which provides an alternative mechanism for long length adjustment of a tension bar, via a detent mechanism. Detent assembly  200  includes a corrugated tube  204  housing a detent  202 . A detent push button  220  controls operation of the detent mechanism. 
       FIGS. 13A and 13B  are side sectional views corresponding to details  13 A,  13 B respectively of the detent assembly  200  of  FIG. 12 . In order to engage the long adjustment detent assembly  200 , the user pushes down the detent button  220  to apply a tangential force to the push rod  214  within clutch rotor  218 , at the applied force contact point. The movement of push rod  214  in turn moves the profiled head  208  to the left. Traversal of the profile head  208  to the left allows the ball bearings  212  to move towards the interior of the head casing  210 . The inward displacement of ball bearings  212  provides clearance between corrugations at interior profile of the corrugated tube  204 , and the ball bearings. In this configuration, since the ball bearings  212  are no longer held in place within corrugated tube  204 , the detent  202  of detent assembly  200  is free to move as indicated by the arrow, compressing the compression spring  206 . 
       FIG. 14  is an exploded view of components at the clutch end of the long adjustment detent assembly  200  of  FIG. 12 , showing a mechanism for disengagement of long adjustment. When a user presses and releases the detent push button  220 , a plastic fin  228  held in compression retracts the push button  220 . The fin  228  is located on the ABS plastic casing  216 . As an alternative to the plastic fin  228 , the long adjustment detent assembly could incorporate a spring to retract the push button  220 . Once the push button is retracted, the force applied onto the push rod  214  is removed. The release of compression spring  206  returns the detent assembly  200  into its locked configuration in which the ball bearings  212  are held in place within corrugated tube  204 . 
       FIG. 15  is an exploded view of components at the clutch end of an adjustable blinds assembly that provides short adjustment of the width between the first and second end plates, using a dial-actuated adjustment mechanism, spur gear assembly with dial  225 . Components of the adjustable blind assembly seen in  FIG. 14  include corrugated tube  204  joined to a threaded nut  248 . Threaded pin or screw  242  is mounted within threaded nut  248 , and is keyed to a bronze radial slip clutch  240  by a square key  244 . 
     A casing  230 , together with end cap  256 , acts as a housing for components of the short adjustment assembly. These components includes a slip clutch  240  and plunger adapter  246 , i.e., radial clutch gear. Other components include spur gear system  232 ,  234 , and an adjustment dial  238  that is coupled to spur gear  232  by pinion adaptor  236 . End cap  256  covers working components of the short adjustment assembly, and is secured to casing  230  via screws  226 . A resilient end pad  224  secured to metal end cap  256  provides friction and dampens the force of the short adjustment mechanism against the window frame. In an embodiment, the end cap  256  is formed of a metal, the casing  230  is formed of an engineering plastic, and the end pad  224  is formed of rubber, it being understood these materials are merely exemplary. 
     The dial adjustment system of  FIGS. 16 and 17  provides small, continuous length adjustments (e.g., ±0.25 in) of the adjustable blinds assembly of  FIG. 15 .  FIG. 16  is an interior view of a dial adjustment assembly for short adjustment of the adjustable blinds assembly, and  FIG. 17  is a side sectional view of the short adjustment end. The mechanism uses a spur gear system  232 ,  234  to transfer torque from the adjustment dial  238  to the ACME screw  242 . Rotation of the screw  242  within the ACME threaded nut  248  provides linear displacement of the corrugated tube  204 . The torque transferred from an adjustment dial  238  to the ACME screw  242  is limited by a radial slip clutch  240 . The dial adjustment system of  FIGS. 16 and 17  permits short adjustment of the detent assembly  200  manually, without requiring tools. 
       FIG. 18  provides a detail schematic of a radial slip clutch system for the dial adjustment assembly of  FIG. 16 . The radial clutch system is comprised of a bronze radial slip clutch  240 , and a plunger adapter  246 . The system utilizes ball plungers housed within the plunger adapter  246 , to provide a gripping force onto the radial clutch  240 . When a desired overload force is reached, the ball plunger compresses thereby allowing the bronze radial clutch to slip. This system is used to prevent any wall or window frame damage caused by high normal force loading. 
     In an embodiment, as a pivot compensation mechanism to compensate for wall misalignment and mounting error, an ABS plastic casing  230  at the short adjustment end has been designed with an allowance, e.g., ±2° allowance. This allowance may be achieved through use of flexible plastic prongs (not shown) attached to the corrugated tube  204 , and through a minor differential slip between the bronze slip clutch  240  and the plunger adapter  246 . 
       FIG. 19  is a perspective view, and  FIG. 20  is a side sectional view, of a bushing-spring assembly from the adjustable blinds assembly with detent mechanism of  FIGS. 15-18 . To provide added bearing support to the assembly including detent  202 , and corrugated tube  204  with corrugated tube end cap  258 , a bushing-spring “splint” casing is utilized. The mechanism is made of two bushings  260 ,  266 , including a corrugated tube bushing  266  placed around corrugated tube  204 , and a detent bushing  260  around the detent assembly  202 . These bushings are held together by three aluminum rods  264  with screws  268 ,  270  at either end. The detent bushing  260  is held fixed to the aluminum rods, but allowed to slide through the corrugated tube bushing  266 . However, the travel is restricted by screws  268 , and by compression springs  262  on the other side. This creates a support structure with slight play along the travel axis, dampening intermittent forces exerted on the assembly during operation. 
       FIG. 21  is a side sectional view of an adjustable blinds assembly  300  that provides long adjustment of the tension bar using a conical wedging mechanism. Adjustable blinds assembly  300  incorporates a cone  312  and an expander  314 , which provide a frictional engagement mechanism for long adjustment of a tension bar that includes a female tension bar  308  and a male tension bar  306 . 
     The adjustable blinds assembly  300  activates a mechanism (not shown) on the end of the male tension bar  306  adjacent a clutch end plate  316 , to move the pull-rod  310  in and out of the male tension bar  306 . For example, the pull-rod activation mechanism may be a threaded dial, a lever, a gear assembly, or a button. Inward motion of the pull-rod  310  pulls the cone  312  into the expander  314 , creating a wedge. As best seen in the detail view of  FIG. 21 , this wedge increases the friction between the outer surface of the expander  314  and the internal wall of female tension bar  308 . This friction will hold the male and female tension bar at a set distance, and allow the blinds assembly  300  to be tensioned without retracting. In an embodiment, this conical wedging mechanism applies a high level of friction between the female tension bar  308  and the expander  314 . The friction between the cone  312  and expander  314  is relatively low, allowing the cone  312  to move freely within the mechanism. 
     An advantage of this wedge-based method of long adjustment is that the blinds can be expanded continuously to any length within the mechanism&#39;s range. That is, this long adjustment mechanism is not limited to discreet lengths, unlike the detent long adjustment mechanism of  FIGS. 15-18 , or the lever long adjustment mechanism of  FIGS. 4-6 . 
       FIG. 22  is a side sectional view of the clutch side of an adjustable blinds assembly with a short adjustment mechanism  330  including a worm set. A worm set  348 ,  350  is used to extend an end plate  332 , in order to close off small gaps and to and apply pressure against a window casement (not shown). The worm set includes a worm  350 , which can be rotated manually by a user using a tool  360  such as a torque knob, an Allen key, or a hex key. As the worm is rotated, the input torque is multiplied through the worm set  348 ,  350  by a gear ratio, for example of 7.5, allowing the user to apply large amount of force through the assembly with very little effort. As the worm gear  348  rotates, it turns a slip clutch  354  along with it which causes the threaded shaft  338  and end plate  332  to displace outwards, applying force against the window casement. The worm set is contained between a housing  346  adjacent end plate  332 , and a clutch end  352 . 
     As the blind is tensioned using this method, the load from the end plate  332  is transferred through the threaded shaft  338 , through the slip clutch  354 , through to a steel nut  342 , then bronze bushing  344 . These mechanisms are contained within a clutch housing  336 . Finally, the load from end plate  332  is transferred through the tension bar  334  to another end plate (not shown), pressing against an opposing window casement at the idler end of the mounting system. 
     As the short adjustment mechanism is tightened through the worm, the normal force of the assembly  330  may increase to a point that will cause the slip clutch  354  to slip at a pre-determined force. This feature protects the blinds or window casement from any damage due to excessive tensioning of the blinds system. The operation of the slip clutch also will signal to the user to stop tensioning the short adjustment mechanism  330 . A spring  340  is included to absorb axial play from temperature changes and vibrations. In an embodiment, the end-plate  332  swivels around a joint, to accommodate uneven window casements. 
     The above disclosed embodiments provide a mounting system for a roller blind, in which a mechanism for raising and lowering a window covering rolled around a roller tube includes a clutch. The roller tube is hollow and the clutch includes a central recess, i.e., the clutch includes a hollow center. A tension bar extends through the hollow roller tube and the central recess of the clutch. In alternative embodiments, the mounting system with tension bar can be used with other window covering systems, i.e., systems for spreading and retracting a window covering. In one embodiment, in lieu of a hollow roller tube, the window covering system includes a headrail, and a mechanism associated with the headrail for spreading and retracting a window covering. The window covering system includes a continuous cord loop extending below the headrail for actuating the mechanism to spread and retract the window covering, wherein this mechanism includes a clutch that engages the continuous cord loop. Rather than extending through a hollow roller tube, the tension bar extends through the headrail, and through a central recess of the clutch. End members are coupled to opposite ends of the tension bar, to frictionally engage first and second sides of the window frame. The window covering system with headrail may incorporate a long adjustment mechanism for adjusting the length of the tension bar, and/or may incorporate a short adjustment mechanism for adjusting the width between the end members over a short distance, as described above. 
     While various aspects and embodiments have been disclosed, other aspects and embodiments are contemplated. The various aspects and embodiments disclosed are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims. The foregoing method descriptions are provided merely as illustrative examples and are not intended to require or imply that the steps of the various embodiments must be performed in the order presented. As will be appreciated by one of skill in the art the steps in the foregoing embodiments may be performed in any order. Words such as “then,” “next,” etc. are not intended to limit the order of the steps; these words are simply used to guide the reader through the description of the methods.