Abstract:
A tensioning, releasable mounting device (9) for a window covering structure mountable in a window recess (R) and including spaced apart beams (3, 4) supporting one or more tensioned cords (2) supporting and guiding a covering panel (1). The mounting device is mounted on each end of at least one beam, and is moveable between an active position, in which each cord (2) is tensioned, and a second position in which each cord (2) is slackened, so that the window covering is easily removed from the window recess.

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The invention relates to a window covering. More particularly, the invention relates to a window covering mounted in a window recess and including spaced apart beams with one or more cord members tensioned therebetween for supporting and guiding a covering panel. 
     2. Background of the Invention 
     Window coverings can take different forms. A window covering can for instance be a pleated material or horizontally extending lamellar material. Such coverings are conventionally held in the plane between spaced rigid beams by one or more tensioning cords so that the covering also remains tautly suspended. Such coverings are useful in slanting windows such as skylights. Because of the tension on the tensioning cords it is difficult to remove the window covering in order, for example, to clean a glass window mounted in the window frame. See U.S. Pat. No. 4,733,711 issued Mar. 29, 1988, to S. Schon for &#34;Folding Blind, Composite Folding Blind and Coupling Strip Therefore.&#34; 
     OBJECTS OF THE INVENTION 
     The principal object of the present invention is to provide an improved tensioned cord mounted window covering assembly which is easily released for removal from a window recess in which it is mounted and also rapidly inserted and mounted in the window recess with the cords reset to the correct tension. 
     Another object of the present invention is to provide an improved releasable mounting mechanism for tensioned cord mounted window covering assemblies. 
     SUMMARY OF THE INVENTION 
     A preferred embodiment of the invention is embodied in a tensioning and mounting device formed by an eccentric lever mechanism arranged on each end of one of the beams for tensioning the cords. 
     According to one embodiment of the invention, the tensioning and mounting eccentric lever mechanism is assembled on an auxiliary beam which is fixed to a main beam supporting the tensioning cords. At least one end face of the auxiliary beam is provided with a rotatable lever arm engagable with a bracket mounted in the window recess. After mounting the beam or beams on the other end of the window covering in the window recess, with or without the same eccentric mechanism, the auxiliary beam and therewith the main beam for tensioning can be secured in place at the correct tension cord position. 
     In order to enable easy removal of the covering and the beams, the lever arm co-acts with an anchor plate fastened against the window recess, which plate is provided with a hook-like recess in which the arm is detachably and rotatably supported. 
     The above construction according to the present invention also lends itself to arrangement of a second beam close to the main beam, such that both auxiliary beams can be protected at the upper and lower limits of the window recess. This offers the advantage particularly in the case of windows with great light incidence that a ventilation gap is created at either the top or bottom or both edges of the covering, whereby the temperature in the space between the window covering and the glass plate will not rise too high. 
     Above mentioned and other features of the invention will be further elucidated in the drawings and description of the invention. 
    
    
     DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows a perspective view of a window covering in the form of a pleated material, provided respectively with the tensioning and eccentric mechanism according to the invention. 
     FIG. 2 shows a standing section of the window covering of FIG. 1. 
     FIG. 3 is a perspective view corresponding with FIG. 1, but with the parts of the eccentric mechanism in exploded view. 
     FIG. 4 is a perspective view on enlarged scale of the lever arm in the eccentric mechanism according to the invention. 
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
     Referring to FIG. 1, a window covering is formed by a pleated material 1 which consists of a length of material folded in zig-zag form and respectively guided and supported by tensioning cords 2 fastened between a first beam 3 secured to the top edge of the material 1 and a second beam 4 adjacent the bottom side of the material 1. A bottom tubular beam 5 is fixed to the bottom edge of the pleated material 1 and slidably mounted on the cords 2 so that the beam 5 can be moved upwardly or downwardly along the tensioning cords 2 as shown in FIG. 3. Such a construction of a window covering is generally known for pleated material curtains. 
     The window recess can have any appropriate configuration or shape. In the embodiment shown, the window recess R is defined by the periphery of a window frame F mounting a glass window plate G. 
     The beams 3 and 4 are tubular and the tensioning cords 2 are threaded in or secured thereto in a suitable manner as shown in FIG. 3. The cords 2 are held at the desired tension by tensioning means such as a draw spring 2a (FIG. 3) housed in the tubular sliding beam 5. 
     One or both the second beam 4 and the first beam 3 are fixed to a respective auxiliary or mounting beam 6, 6&#39; using spring clamps 7 fixed thereon. The clamps 7 are substantially U-shaped and have inwardly facing flanges which snap into grooves 8 of first beam 3 or second beam 4. The auxiliary beams 6, 6&#39; may have any desired cross-section and are formed of a length which is slightly shorter than the length of the associated second beam 4 or first beam 3. Each end face 10 of an auxiliary beam 6, 6&#39; is provided with a closing plate 11 having an extending boss or plug 12 which fits into the hollow end space 13 of the auxiliary beam 6, 6&#39;. The closing plate 11 has a height which is greater than that of auxiliary beam 6, 6&#39; to form an extension on which a mounting protrusion or pin 14 is formed, which pin extends axially from the end of the beam 6, 6&#39;. 
     In accordance with the present invention, a releasable tensioning and mounting device 9 releasably mounts an auxiliary beam in the window recess. To this end, one of the beams 6 is provided at each end with a tensioning and mounting device 9 formed by a swingable toggle or lever arm 15 provided with a hole 16 that receives the pin 14 of the closing plate 11. The lever arm 15 is provided with a knob-like end portion or handle 17 which can be gripped to swing the lever arm on the pin 14. Arranged on the end of the lever arm 15 opposite from the pivot hole 16 is a projecting pin 18. 
     For mounting the window covering 1 in the window recess R, anchor plates 20 are fastened against the sides of the window frame F by screws 21. Each anchor plate 20 has an end portion defining a hook 22 forming a hook recess or slot 23 for receiving and holding an inserted pin 14, 18. The length of the auxiliary beam 6 with the closing plate 11 and lever arm 15 mounted thereon is such that the pins 18 engage the hooks 22 of the adjacent anchor plates 20. 
     The window covering 1 and associated mounting beams 6, 6&#39; are mounted in a window recess R by engaging the pins 14 on the one beam 6&#39; in the hook slots 23 of associated anchor plates 20. The first beam 6&#39; is thereby mounted in the window recess R. The opposite mounting beam 6 is secured in the window recess by engaging the pins 18 of the swingable lever arm 15 in the hook slots 23 of the associated anchor plates 20 and then, by gripping the handle knobs 17, pivoting the lever arms to tension the cords 2 against the biasing force of the tensioning spring 2a and snap lock the mounting beam 6 into place. The second beam 4, being secured to the mounting beam 6 by the clips 7, is thereby mounted in the window recess R and the cords 2 tensioned. 
     To release the cord tension so that the second beam 4 and mounting beam 6 can easily be removed, the cords 2 are slackened by releasing the eccentric mechanism or lever arm 15. To this end, each lever arm 15 is swung away from the glass plate G (see FIG. 2) and rotated upward according to arrow P1. The pin 18 describes a circular path relative to pin 14, whereby the distance between the beam 6 and the first beam 3 becomes smaller. The cord 2 slackens and, in the slackened state, the pin 18 can be lifted from the recess 22 in the direction of the arrow P2 (see FIG. 2). One end of the window covering 1 is thus released from the window recess R and can be folded upward, whereafter the glass plate G becomes accessible. 
     In the embodiment shown it is possible to lock the lever arm 15 to the anchor plate 20, as shown in FIG. 4. For this purpose the knob-like portion 17 is extended on the side facing toward the anchor plate relative to the body plate of arm 15 to form an elongation or lip 25 which extends into an outwardly opening chamber or recess 26 defined on the anchor plate 20. By turning or bending the knob or handle 17 away from the anchor plate 20, in the direction of arrow P3, which is possible because of the relatively thin, stiffly bendable body plate of arm 15, the arm 15 is released and can then be rotated in the manner described above. Conversely, re-locking takes place by snapping the protruding lip 25 into the chamber or recess 26. The top beam 6&#39; with the first beam 3 fixed thereto can be detached from the window frame by lifting the pins 14 out of the hook-like recesses 22, in the direction of arrow P4 as shown in FIG. 2. 
     Alternatively, the first beam 3 can be mounted directly against the top boundary of the window recess R. It is further possible to have the eccentric lever 15 point not downward, as shown, but upward in the tensioned position of the second beam 4 so that the second beam 4 with the auxiliary beam 6 coupled thereto, lies directly against the bottom boundary of the window recess R whereby the window recess R is fully covered by the window covering. 
     Further, it is possible to mount the lever arm 15 and closing plate 14 directly onto the second beam 4 without adversely affecting the action of the eccentric mechanism.