Bottom-up/top-down retractable cellular shade

Information

  • Patent Grant
  • 6834701
  • Patent Number
    6,834,701
  • Date Filed
    Tuesday, March 18, 2003
    21 years ago
  • Date Issued
    Tuesday, December 28, 2004
    19 years ago
Abstract
A covering for an architectural opening includes a head rail, a bottom rail with a take-up roller therein and an intermediate rail with both the intermediate rail and bottom rail suspended from the head rail, a fabric material interconnecting the intermediate rail with the bottom rail and being adapted to be wrapped around the roller in the bottom rail, said fabric including a pair of vertically oriented sheets that are horizontally spaced by a plurality of vertically spaced horizontal vanes with the vanes being movable between open and closed positions by opposite vertical movement of the sheets of material. A first control system is provided for raising and lowering the bottom rail and a second control system for raising and lowering the intermediate rail as well as tilting the intermediate rail to effect an opening or closing of the vanes.
Description




BACKGROUND OF THE INVENTION




1. Field of the Invention




This invention relates generally to retractable coverings for architectural openings or the like that include a pair of vertically oriented sheets horizontally spaced by a plurality of vertically spaced horizontally extending vanes. Oppositely directed vertical movement of the sheets causes the vanes to pivot about horizontal longitudinal axes between open and closed positions. In the open position, the vanes are horizontally disposed defining a gap therebetween permitting the passage of vision and light, and in a closed position, the vanes are substantially vertically oriented and overlap slightly to block the passage of vision and light there through. The coverings are retractable by lifting a bottom rail or lowering an intermediate causing the sheets of material and interconnected vanes to wrap around a horizontal roller. More specifically the present invention relates to a covering of the above-noted type wherein the top of the covering can be lowered or the bottom raised and the vanes opened or closed at any relative position of the bottom rail with respect to the top of the covering.




2. Description of the Relevant Art




Coverings for architectural openings such as windows, doors, archways and the like, have taken numerous forms over many years. Early simple forms of such coverings amounted to fabric draped or otherwise suspended across an opening while in recent years more sophisticated coverings have been developed.




By way of example, venetian blinds have become a popular form of coverings for architectural openings wherein a plurality of vertically spaced, horizontally extending slats are pivotally supported by cord ladders so that the slats can be pivoted or tilted about horizontal longitudinal axes to move the covering between open and closed positions or the slats can be gathered into a vertical stack adjacent the top of the architectural opening in a retracted condition of the covering.




More recently such venetian blinds have been designed so as to not only retract vertically by lifting a bottom rail toward the headrail of the covering but by also dropping a top rail toward the bottom rail and such coverings are commonly referred to as bottom-up/top-down coverings. As will be appreciated, in a bottom-up/top-down covering, the slats can be gathered adjacent to the top of the opening or the bottom of the opening and can further be tilted at intermediate locations to permit or prevent the passage of vision and light therethrough.




More modern coverings for architectural openings have been referred to as cellular coverings wherein a plurality of horizontally extending, vertically stacked cells can be extended across an opening or gathered adjacent an edge of the opening in a stacked condition with the cells collapsed adjacent to each other. One disadvantage with this type of cellular covering resides in the fact that when the covering is extended across an opening, vision and light are blocked.




To overcome the shortcomings in the afore-noted cellular-type coverings, a new version of a cellular covering includes a pair of parallel vertically disposed sheets of sheer-type fabric which are normally suspended in horizontally-spaced relationship and include a plurality of vertically spaced horizontally extending vanes, which may be flexible, extending therebetween. By moving the sheets in opposite vertical directions, the vanes can be moved between open and closed positions so that in an open position, the vanes are disposed substantially horizontally to permit the passage of vision and light therebetween, and in a closed position, are disposed substantially vertically and overlap to block the passage of vision and light. Of course, in the closed position, the sheets of sheer material are disposed closely adjacent to each other with only the vanes separating the sheets. This type of cellular shade is moved from an extended position, wherein it extends across the architectural opening, to a retracted position by rolling the two sheets with the vanes therebetween about a roller disposed in the headrail at the top of the opening. Of course, to extend the covering across the opening, the roller is simply rotated in the opposite direction and a weighted bottom rail pulls the sheet material with the vanes secured thereto downwardly by gravity. Such coverings to date have only been operable by drawing the bottom rail upwardly and rolling the fabric material, comprised of the sheets and vanes, about a roller within the head rail.




More versatility in cellular coverings of this latter type would be desirable and it is to that end that the present invention has been developed.




SUMMARY OF THE INVENTION




A cellular covering for architectural openings in accordance with the present invention includes a head rail, a bottom rail, and an intermediate or mid rail with a fabric structure secured to and extending between the intermediate rail and the bottom rail. The fabric structure includes front and rear sheet materials adapted to be suspended vertically and with a plurality of vertically spaced horizontally extending vanes interconnecting the two sheets. The vanes are preferably flexible, even though this is not a requirement, and are of a width and spacing such that when vertically oriented, will overlap each other. When horizontally oriented, the vanes define spaces therebetween through which light and vision can pass.




The bottom rail includes a roller about which the fabric material can be selectively wrapped or unwrapped. The bottom rail is suspended from the headrail by a first control system that is manually operated so that the bottom rail can be selectively raised toward the top rail and positioned at any location between its lowermost position, which it assumes when the covering is fully extended, and a retracted position adjacent the headrail when the covering is fully retracted. The roller in the bottom rail around which the fabric structure can be wrapped and unwrapped is spring biased. The bias is in a direction so as to encourage wrapping of the fabric structure about the roller when the fabric structure is fed into the bottom rail as when the bottom rail is raised or the intermediate rail is lowered. When the bottom rail is lowered or moved by gravity away from the headrail causing the fabric structure to unroll from the roller, the weight of the bottom roil is sufficient to allow the fabric to unwind from the roller against the bias of the spring in the roller.




The intermediate rail is also suspended from the headrail and is adapted to be manipulated by a second control system which allows the intermediate rail, to which the upper edge of the fabric structure is secured, to move upwardly or downwardly. When moving the intermediate rail downwardly from the head rail, the fabric structure is shifted downwardly away from the head rail and fed into the bottom rail where it is wrapped around the roller within the bottom rail due to the bias of the roller encouraging the fabric to be wrapped therearound. The intermediate rail can be positioned at any location between the head rail and the bottom rail so as to define a gap between the intermediate rail and the head rail where there would be no fabric material.




The intermediate rail can also be pivoted about a horizontal longitudinal axis by the second control system such that the front and rear sheets of material are shifted in a opposite vertical directions thereby causing the horizontal vanes to shift between an open substantially horizontal position, permitting the passage of vision and light therebetween, and a closed substantially vertical position, wherein the vanes overlap and block vision and light therethrough.




It will be appreciated that the covering of the present invention is a bottom-up/top-down covering with the bottom rail and intermediate rail being movably positionable anywhere in between their extreme lower and upper positions so that the fabric structure between the bottom rail and the intermediate rail can be extended to any desirable degree and positioned at any location across the opening.




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 an isometric view of the covering of the present invention in a fully extended condition with the vanes open.





FIG. 2

is an isometric view of the covering of the present invention with the intermediate rail partially lowered and the vanes in a closed position.





FIG. 3

is an isometric view of the covering of the present invention with the intermediate rail lowered and the vanes in an open position.





FIG. 4

is an enlarged isometric view of the covering of the present invention with the bottom rail partially raised and with the vanes in an open condition.





FIG. 5

is a vertical section taken through the covering of the present invention as seen in FIG.


3


.





FIG. 6

is a vertical section taken through the covering of the present invention as seen in FIG.


2


.





FIG. 7

is a vertical section taken along line


7





7


of FIG.


4


.





FIG. 8

is a section similar to

FIG. 7

with the vanes in a closed rather than an open position.





FIG. 9

is a diagrammatic isometric view showing the covering of the present invention in a fully extended position and with the vanes in an open position and further illustrating the control mechanisms for operating the covering.





FIG. 10

is a diagrammatic isometric view similar to

FIG. 9

with the intermediate vane partially lowered.





FIG. 11

is a diagrammatic isometric view similar to

FIG. 9

with the vanes closed rather than open.





FIG. 12

is a diagrammatic isometric view of the covering of the present invention with the bottom rail fully raised into a position adjacent to the intermediate rail.





FIG. 13

is a fragmentary top plan view taken along Line


13





13


of

FIG. 3

showing one end of the intermediate rail and an end cap mounted thereon.





FIG. 14

is a fragmentary section taken along Line


14





14


of FIG.


13


.





FIG. 15

is a fragmentary section taken along Line


15





15


of FIG.


13


.





FIG. 16

is a fragmentary section similar to

FIG. 15

with the intermediate rail rotated through 90°.





FIG. 17

is a fragmentary section similar to

FIG. 14

with the vane having been rotated through 90°.





FIG. 18

is a fragmentary isometric looking at an end of the intermediate rail.











DETAILED DESCRIPTION OF THE INVENTION




A covering


20


in accordance with the present invention is shown in

FIG. 1

to include a head rail


22


, a bottom rail


24


, an intermediate rail


26


, a flexible fabric material or structure


28


extending between the intermediate rail and the bottom rail and operating cords


30


and


32


for operating first


34


and second


36


control systems, respectively (

FIGS. 9-12

) for the covering. The first control system


34


enables movement of the bottom rail vertically between a fully retracted condition of the covering as shown, for example, in

FIG. 12

, and a fully extended condition as shown in FIG.


1


. The second control system


36


is utilized to not only tilt the intermediate rail for purposes to be described later, but to also move the intermediate rail vertically between the fully retracted position of

FIG. 1 and a

fully extended position (not shown) wherein the intermediate rail is positioned adjacent to the bottom rail when the bottom rail is in its fully extended position of FIG.


1


. Both control systems are adapted to removably position the associated intermediate or bottom rail at any position between the fully retracted and extended positions.




The head rail


22


includes a pair of brackets


38


adapted to mount the head rail to the frame or another location adjacent to an architectural opening, such as a window, door, archway, or the like.




The fabric material


28


that extends between the intermediate rail


26


and the bottom rail


24


is comprised of front


40


and rear


42


flexible sheets of material such as sheer fabric, with the sheets being suspended from the intermediate rail in a horizontally spaced, vertically oriented condition when the fabric is fully extended as illustrated in

FIG. 1. A

plurality of vertically spaced, horizontally disposed vanes


44


extend between and are operatively connected to the sheets of material and while the vanes could assume different structures, in the preferred embodiment, they too are a flexible fabric material which may be the same or different than the material from which the sheets are made. Preferably, the vanes are opaque or translucent while the sheet material is transparent or translucent.




As will be appreciated with the operation of the covering to be described later, the fabric


28


is movable by the intermediate rail


26


between an open position illustrated in

FIG. 1 and a

closed position illustrated in FIG.


11


. In the open position, the vanes


44


can be seen to assume a substantially S-shaped cross sectional configuration and are disposed substantially horizontally so as to define a space between adjacent vanes. This permits the passage of vision and light between the vanes and since the sheet materials


40


and


42


along the opposite side edges of the vanes are transparent or translucent, some degree of, light and vision is permitted through the fabric material when the covering is in the open condition of FIG.


1


.




In the closed condition of

FIG. 11

, the fabric sheets


40


and


42


have been shifted vertically in opposite directions relative to each other so that the vanes


44


assume a substantially flat vertical planar orientation with adjacent vanes slightly overlapping to block, at least to some degree, the passage of vision and light through the fabric. Accordingly, the covering is movable between open and closed conditions by shifting the fabric sheets


40


and


42


in opposite vertical directions relative to each other as will be explained in more detail later.




The bottom rail


24


, as best seen in

FIGS. 5-12

, includes an elongated rotable roller or roll bar


46


about which the fabric


28


can be wrapped or unwrapped with the roll bar being biased in a clockwise direction (as viewed in the drawings) by a conventional internal roller spring (not seen). The strength of the roller spring is determined by factors, which will become more apparent hereafter.




The first control system


34


shown at the left end of the covering


20


includes a pair of elongated flexible lift cords


48


or the like which extend from the headrail


22


to the bottom rail


24


at opposite ends of the bottom rail and are adapted to be extended or retracted by the closed loop flexible operating cord


30


or the like suspended at the left end of the covering for ready access by an operator of the covering. As will be explained in more detail later, movement of the operating cord


30


in one direction or the other causes the bottom rail to lift or lower through a retraction or extension of the lift cord


48


at each end of the covering. Retraction of the lift cords causes the bottom rail


24


to rise while retaining its horizontal orientation and move towards the head rail


22


. As the bottom rail rises toward the head rail, the bias on the spring roller in the bottom rail causes the fabric to be wrapped around the roller. As the fabric is wrapped around the roller, it antomatically moves the front and rear sheets of material


40


and


42


respectively toward each other in a manner to be described later thereby shifting the vanes


44


to a closed position so the vanes lie flat between the sheets of material as the fabric is wrapped about the roller.




As is probably seen best in

FIGS. 9-12

, the first control system


34


is mounted in the head rail


22


and includes a horizontal rod


52


supporting a pulley


54


at its left end and supported by a bearing


56


at its right end. The pulley


54


receives the endless operating cord


30


so that movement of the operating cord in one direction or the other causes a corresponding rotative movement of the pulley and the rod


52


which is fixed thereto for unitary movement therewith. The lift cords


48


associated with opposite ends of the bottom rail


24


are secured to the rod so as to be wrapped or unwrapped therefrom as the operating cord is moved.




It will therefore be appreciated that if the bottom rail


24


is in the fully extended position of

FIG. 1

, for example, rotation of the rod


52


in a clockwise direction will cause the lift cords


48


at opposite ends of the bottom rail to be wrapped around the associated rod causing the bottom rail to rise in a horizontal orientation and as it rises, the spring bias in the roll bar


47


causes the fabric material


28


to accumulate and be wrapped around the roller. It does not matter whether or not the fabric is in the open position of

FIG. 1

or the closed position of

FIG. 2

when the bottom rail is lifted as the fabric is passed through a narrow slot


58


provided in the top surface of the bottom rail prior to being wrapped about the roll bar forcing the fabric sheets


40


and


42


together, while in the bottom rail but unaffecting the fabric when outside the bottom rail. When the operating cord


30


for the first control system is moved in a counterclockwise direction causing the rod


52


to rotate correspondingly, the lift cords are allowed to unwrap from the rod and the bottom rail moves downwardly under the force of gravity and against the bias of the roll bar spring so the fabric material is unrolled from the roll bar and allowed to slide outwardly through the narrow slot


58


into a deployed position between the intermediate rail


26


and the bottom rail


24


. It will be appreciated that the strength of the spring in the roll bar


46


is sufficient to wrap the fabric therearound as the bottom rail is raised but not so strong as to prevent gravity from lowering the bottom rail as the lift cords are extended.




As will be appreciated by reference to

FIGS. 9-17

, the intermediate rail


26


has a relatively flat ovular main body


60


that is hollow in construction and has end caps


62


in opposite ends thereof. The end caps are rigid in nature and can be made of any suitable material such as plastic and serve partially to provide closure to the open ends of the ovular body. The ovular body needs to be somewhat rigid so as to support the fabric


28


and in particular, the front sheet


40


of the fabric is supported from the front edge


64


of the intermediate rail while the back sheet


42


of the fabric is supported from the rear or back edge


66


in a conventional manner.




Each end cap


62


is provided with a plurality of slots formed transversely of the intermediate rail and adapted to receive the lift cords


46


for the bottom rail and tilt/lift cords


68


for the intermediate rail. The tilt/lift cords are part of the second control system


36


that will be described later. As seen in

FIGS. 13 and 14

, a first innermost slot


70


is formed from the rear edge


66


of the end cap and terminates at a location approximately ¾ of the way across the width of the end cap. The slot extends completely through the end cap from top to bottom. A wrap pin


72


is defined in the slot so as to extend from one side of the slot to the other adjacent to but slightly spaced from a block of material


74


defined adjacent to the front edge of the vane. The wrap pin


72


is adapted to receive the tilt/lift cord


68


in a manner such that the cord wraps around the pin twice for a purpose to be described later.




A second pair of aligned slots


76


and


78


are disposed outwardly from the innermost slot


70


as seen in

FIGS. 13

,


15


, and


16


. The slot


76


of the pair extends from the rear edge


66


of the end cap along the top half of the end cap slightly more than half the distance to the front edge


64


of the end cap while the second slot


78


of the pair extends from the front edge


64


of the end cap along the bottom half of the end cap to slightly past the center of the end cap. The associated lift cord


46


for the bottom rail


24


passes through the pair of slots


76


and


78


as best seen in

FIGS. 13 and 15

so that when the intermediate rail


26


is horizontally disposed, there is a passage communicating with both slots


76


and


78


of the pair to accommodate the passage of the lift cord transversely through the slots. Further, when the intermediate rail is pivoted through 90° as shown in

FIG. 16

, the lift cord


46


again passes through the slots, this time longitudinally of the slots. It will be appreciated, however, that when the intermediate rail is horizontally disposed as shown in

FIG. 15

, the solid portions


80


and


82


of the end cap that are aligned with the slots


76


and


78


engage the lift cord and prevent the intermediate rail from pivoting in a counterclockwise direction while permitting pivotal movement in a clockwise direction until the intermediate rail becomes vertically oriented as shown in

FIG. 16

where the lift cord again engages the solid portions, this time along different surfaces thereof, preventing further pivotal movement. When the vane is vertically oriented as in

FIG. 16

, of course, the vane can be pivoted in a counterclockwise direction but prevented from further pivotal movement in a clockwise direction.




As probably best appreciated by reference to

FIGS. 9-12

, the second control system


36


includes a horizontally disposed rod


84


carrying a pulley


86


at one end and is supported at its opposite end in a bearing


88


for rotative movement that is created by the second endless operating cord


32


operatively engaged with the pulley


86


. Movement of the second operating cord in one direction or the other, therefore, causes the rod


84


to rotate in a corresponding direction. A pair of the flexible tilt/lift cords


68


are secured at one end to the rod


84


and are adapted to be wrapped around or unwrapped from the rod depending upon the direction of movement of the operating cord


32


. One of the tilt/lift cords


68


extends from the rod


84


to the left end of the intermediate rail


26


where it extends downwardly and is wrapped twice around the associated wrap pin


72


in the end cap


62


before having the free end of the cord extend upwardly where it is anchored at


90


to a bottom surface of a top wall


92


of the head rail


22


. The second tilt/lift cord


68


also extends from the rod


84


downwardly to the wrap pin in the end cap at the opposite end of the intermediate rail where it too is wrapped twice around the wrap pin and then extends upwardly where the end of the cord is secured at


94


to a bottom surface of the top wall


92


of the headrail.




The tilt/lift cords associated with the second control system extend along a front side of the associated wrap pin


72


before being wrapped therearound and extending upwardly from the rear side of the wrap pin toward their locations of anchor to the top wall


92


. It will, therefore, be appreciated that as the tilt/lift cords are unrolled from the associated rod


84


by counterclockwise rotation of the operating cord


32


, the tilt/lift cords become slack along the front edge of the wrap pins so that the wrap of cord about the wrap pins is loose enough to allow the intermediate rail


26


to drop by gravity. Before the intermediate rail drops vertically by gravity, however, it will pivot about a horizontal axis defined by the wrap pins


72


in a clockwise direction inasmuch as the end caps are designed to be heavier along the fronts edges


64


thereof. After the intermediate rail has pivoted through approximately 90 degrees (from the position of

FIG. 15

to the position of FIG.


16


), the lift cords


48


interact with the slots


76


and


78


in the associated end caps of the intermediate rail preventing further pivotal movement of the intermediate rail so that if the tilt/lift cords are continued to be unwrapped from the rod


84


, the looseness of the wrap of the tilt/lift cords about the wrap pins allow the entire rail to drop by gravity while in its vertical orientation of FIG.


11


.




The intermediate rail


26


can be lowered in the afore-noted manner from the fully retracted position of

FIG. 11

to a fully extended position (not shown) adjacent to the bottom rail


24


. This is true regardless of the location of the bottom rail, i.e. whether it is fully extended into its lowermost position or raised fully or partially into an intermediate location above the fully extended position.




However, if the operating cord


32


is moved in a clockwise direction, the tilt/lift cords


68


are caused to wrap about the rod


84


thereby tightening the wrap of the tilt/lift cords about the wrap pins and causing the intermediate rail to initially pivot in a counterclockwise direction causing the tilt/lift cords to switch from the positions shown in

FIG. 16

to the position of FIG.


15


. Once the intermediate rail pivots to the horizontal orientation of

FIG. 15

, the lift cords again operatively engage the end caps terminating the pivotal movement of the intermediate rail whereby further wrapping of the tilt/lift cords about the rod


84


shortens their effective length causing the intermediate rail to rise.




Clutches (not shown) are associated with both the first and second control systems


34


and


36


to permit the bottom rail


24


and the intermediate rail


26


to removably maintain any position between their fully extended and fully retracted positions so the fabric


28


extending therebetween can be extended fully across the architectural opening (FIG.


1


), from the top partially down (FIG.


4


), from the bottom partially up (FIG.


2


). or to any degree there between across an intermediate portion of the opening (FIG.


10


).




It should also be appreciated that the intermediate rail


26


is designed and contoured to fit within the head rail


22


when the intermediate rail


26


is fully retracted regardless of whether or not the intermediate rail is horizontally oriented (

FIG. 7

) or vertically oriented (FIG.


8


). This prohibits undesired light from passing between the head rail and intermediate rail when the intermediate rail is fully retracted.




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 of the invention as defined in the appended claims.



Claims
  • 1. A covering for an architectural opening comprising in combination:a head rail, a bottom rail having a rotatable roller therein biased for rotation in a first direction, an intermediate rail movable vertically between said head rail and bottom rail, a flexible curtain disposed between said intermediate rail and said bottom rail, while being anchored along a top edge to said intermediate rail and to said roller along a bottom edge, a first control system for moving said bottom rail vertically, and a second control system for moving said intermediate rail vertically, whereby relative movement of said intermediate rail toward said bottom rail causes said flexible curtain to be wrapped around said roller and relative movement of said intermediate rail away from said bottom rail causes said flexible curtain to be unrolled from said roller.
  • 2. The covering of claim 1 wherein said flexible curtain includes a plurality of elongated horizontally extending vanes, each vane being movable between open and closed orientations such that the transverse cross section of the vanes hang between being substantially horizontal in the open orientation and substantially vertical in the closed orientation, and wherein said intermediate rail is pivotally movable about a longitudinal axis to move said vanes between the open and closed orientations.
  • 3. The covering of claim 2 wherein said pivotal movement of said intermediate rail is effected by said second control system.
  • 4. The covering of claim 3 wherein said flexible curtain includes a pair of vertically extendable sheets and said vanes are secured to said sheets while being positioned between said sheets, wherein vertical movement of said sheets in opposite directions causes said vanes to move between said open and closed orientations and said pivotal movement of said intermediate rail causes said sheets to move vertically in opposite directions.
  • 5. The covering of claim 4 wherein said intermediate rail has front and rear edges with the front edge being secured to one of said sheets and the rear edge to the other of said sheets.
  • 6. The covering of claim 5 wherein said second control system includes an elongated flexible element operatively connected to said intermediate rail such that movement of said element in one direction causes the intermediate rail to pivot in a first direction and movement of said element in an opposite direction causes the intermediate rail to pivot in an opposite direction.
  • 7. The covering of claim 6 wherein said second control system includes means for limiting the pivotal movement of said intermediate rail between first and second positions which are approximately 90° apart.
  • 8. The covering of claim 7 wherein movement of said element of said second control system includes means for causing said intermediate rail to rise when said intermediate rail is in said first position and to fall when in said second position.
  • 9. The covering of claim 8 wherein said means for limiting pivotal movement and said means for causing said intermediate rail to rise or fall include pins around which said element is wrapped and slots in said intermediate rail through which said element passes.
  • 10. The covering of claim 4 wherein said bottom rail has a relatively narrow slot through which said flexible curtain passes for anchoring to said roller, such that the said sheets and vanes within said bottom rail are closely positioned for wrapping around said roller.
CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No. 60/366,286, filed 20 Mar. 2002, which application is hereby incorporated by reference as if fully disclosed herein.

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Foreign Referenced Citations (2)
Number Date Country
201 17 865 Feb 2002 DE
0 529 591 Mar 1993 EP
Provisional Applications (1)
Number Date Country
60/366286 Mar 2002 US