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RELATED APPLICATIONS 
     This application claims priority to provisional application Ser. No. 60/366,318 filed Mar. 21, 2002 entitled UNIVERSAL BRACKETING AND CAP SYSTEM FOR CASSETTE ROLLER SHADE and incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of Invention 
     This invention pertains to a cassette system for window shades and more particularly to a system that incorporates a roller blind supported by two identical brackets. The cassette system can accommodate one panel that can be deployed by a user in the conventional manner, or can include axially spaced end panels, each panel each panel being deployed independently. 
     2. Description of the Prior Art 
     There are several types of window dressings that can be used to cover windows. One of the most popular types of window dressings are roller blinds. Typically, roller blinds consist of a cylindrical mandrel holding a decorative panel of fabric, plastic or other pliable material. The cylindrical mandrel is formed with a clutch on one side, a pin on the other, and supported by two brackets on each side. The end of the mandrel supported at the pin is freely rotatable. The clutch allows the mandrel to rotate in a controlled manner to allow selectively the raising or lowering of the panel. A control mechanism may,be interfaced with the clutch to allow a customer to operate the roller blind, using a chain or a rope. 
     The simplest roller blinds consist only of the mandrel and the panel, and two end brackets. More advanced blind rollers are contained in cassette housings. The cassettes provide a decorative housing that hides the roller blind (except for the panel), the associated hardware, and can be mounted in a window frame using a variety of mounting fixtures depending on the orientation. 
     Two different cassette systems with roller blinds are known. In one system, the cassettes are provided with roller blinds having a clutch at one end and a pin at the other, as discussed above, with a specific end-cap provided for each type of bracket. Systems of this type are available, for example, from Multifilm of Cuneo, Italy, Arquati of Carrolton, Tex. and Sala Baganza (Parma) Italy. This arrangement has several disadvantages. One disadvantage is that customers demand the ability to install the cassettes with the control mechanism, including the clutch on either the right or the left side of the window. As a result, the cassette systems had to be made with four different types of brackets: two types for a left clutch and a right pin; and two additional types, one for a right clutch and one for a left pin. Yet another disadvantage is that there are several types of clutches are available, and a different type of bracket must be provided for each type of clutch mechanism. 
     Another disadvantage on the manufacturing side is that end caps of these types require complex and expensive tooling, frequently running up to $50,000. 
     Another type of cassette system presently available requires separate end brackets that must be mounted in the window frame and attached to a rail by a screw and finished with a protective cover attached to the bracket. This type of system is available, for example, from Benthin Systems of Germany. Its main disadvantage is that the bracket and its cover add to the cost of the system and are esthetically undesirable. 
     In addition, both systems described above tend to be difficult to assemble. 
     U.S. Pat. Nos. 4,372,432 and 4,433,765 disclose clutch assemblies that are used for roller blinds and other similar devices. 
     SUMMARY OF THE INVENTION 
     According to this invention, a window treatment cassette system includes a head rail with a base, two preferably identical end brackets mounted in the base and a roller blind supported between the brackets. The blind roller includes two end plugs: one for the pin end and one for the clutch. The end plugs are formed on the external surface of the roller with identical slots adapted to receive the respective leg of each supporting bracket. In this manner, the blind roller can be mounted with the clutch plug end on the left or the right, thereby allowing the blind roller to be operated from either side. 
     In an alternate embodiment, the cassette system is provided with a plurality of roller blinds of various lengths, each roller blind supported either between two intermediate brackets or an intermediate bracket and an end bracket. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 shows an exploded view of a cassette system constructed in accordance with the subject invention for a single roller blind; 
     FIG. 1 a  shows a front elevational view of the roller blind used in the cassette system of FIG. 1; 
     FIG. 1 b  shows a front elevational exploded view of the cassette system of FIG. 1A; 
     FIG. 1 c  shows a side elevational view of a clutch plug of the cassette system of FIGS. 1 a ,  1   b;    
     FIG. 1 d  shows a side elevational view of a plain plug of the cassette system of FIGS. 1 a ,  1   b;    
     FIG. 2 a  shows a partial orthogonal view of the head rail for the cassette system of FIG. 1 as seen from the back without the blind roller and the end caps; 
     FIG. 2 b  shows the head rail of FIG. 2 a  with the end bracket removed; 
     FIG. 3 shows a side elevational view of the bracket of FIG. 2 b;    
     FIG. 4 a  shows an orthogonal view of a cassette system for two blind rollers; and 
     FIG. 4 b  shows an orthogonal view of the cassette of FIG. 4 a  with the end plugs removed. 
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     Referring first to FIGS. 1 and 1 a - 1   d , a cassette system  100  constructed in accordance with this invention includes a head rail  12 , two end plugs  14 A,  14 B, a roller blind  15 , two end brackets  16  and two end caps  18 . The end brackets are mounted on the head rail. The end plugs  14 A,  14 B are inserted telescopically into the roller blind  15  and are supported by the end brackets. The cassette system  100  can be secured to the frame of a window or other similar fixture (not shown) by two or more clips  20  that engage the head rail  12 . 
     The roller blind  15  includes a hollow mandrel  30  with a panel  32  wound on the mandrel  30 . Rotating the mandrel  30  in one direction causes the panel  32  to wind up onto the mandrel  30  while rotating the mandrel  30  in the opposite direction causes the panel  32  to wind down, as indicated by arrow A. 
     The ends of the mandrel  30  are hollow to receive end plugs  14 A (shown as an idler) and  14 B (shown as a clutch), respectively. (In fact, the whole mandrel is typically hollow.) End plug  14 A consists of a drum  34  and a bushing  36  rotatably inserted into the drum  36 . End plug  14 B is formed with a drum  38  and a capstan  40 . Drums  34 ,  38  are inserted into the opposite ends of mandrel  30  and are maintained therein by interference fit or by other well known means. 
     The drum  38  includes a clutch (not shown). Capstan  40  includes an opening  42  through which a rope (not shown) such as, for example, a cord or bead chain, can pass through. Within the capstan, the rope passes over a wheel  44  and then exits through opening  42 . Pulling one end of the rope causes the wheel to rotate in one direction. This motion is transmitted to the clutch which then rotates the drum  38  and mandrel  30 . Pulling the other end of the rope causes the mandrel  30  to rotate in the opposite direction. This whole mechanism is well known in the art, as described for example, in U.S. Pat. No. 4,372,432 incorporated herein by reference. 
     As best seen in FIG. 1 c , the capstan  40  has a central scalloped hole  46  on its side surface. The hole  46  defines at least one slot  48  having a maximum diameter width D. The hole  46  could bet shaped to define two different slots disposed, for example, orthogonal to each other, each having a maximum width D. As seen in FIG. 1 d , the bushing  36  has an identical hole  46  with slots  48 . The end plugs  14 A,  14 B are installed and oriented with holes  46  positioned coaxially with the axis of the mandrel  30  and the slots  42  on the respective end plugs disposed in parallel to each other. 
     FIGS. 2 a  and  2   b  show details of the head rail  12  and two end brackets  16  mounted on the head rail  12  so that they face each other. The head rail  12  is made from aluminum, an aluminum alloy and other similar rigid and relatively light weight material. The head rail is formed with a base  50 , a rear wall  52  and a front wall  54 . The base  50  is formed with two L-shaped internal channels  56 . The two channels extend in parallel to define a track for the brackets  16 . The base  50  and the rear wall  52  each have an external rib  58 ,  60 . These external ribs are used to secure the clips  20 . The clips  20  are external mounting brackets. The front wall  54  is essentially decorative and its purpose is to hide the other elements of the cassette from view. 
     The brackets  16  are generally C-shaped with a vertical member  60  and two legs  62 ,  64  oriented perpendicularly to the vertical member  60 . The leg  64  has a width that corresponds to the distance between the channels  56  allowing the brackets to be inserted into the track formed by these channels, as shown in FIG. 2 b . The leg  62  is formed with a small dimple  66  that protrudes slightly to form an interference fit with the base  50 . As a result of this fit, the brackets  16  are held within the track. The leg  64  has a width that is slightly smaller than the distance D defined by the slots  48  on the end plugs  14 A,  14 B. 
     Referring back to FIG. 1, the cassette system  100  is assembled so that the brackets are inserted into the track between the rails  56  and the roller blind is supported on the legs  64  of the brackets  16 . Since these legs  64  are inserted into slots  48 , the bushing  36  and capstan  40  are immobilized thereby allowing the panel  32  to be raised and lowered as described above. Importantly, since the central holes  46  on the end plugs  14 A,  14 B are identical, the two brackets, in this example, are identical as well, thereby reducing the number of parts required, and manufacturing costs. The end caps  18  are made to press fit, as in a manually applied frictional engagement onto the head rail  12 . 
     FIGS. 4 a  and  4   b  show an alternate embodiment of the invention. In this embodiment, a cassette system is shown that can be used for two roller blinds disposed side by side. As can be seen in these Figures, the cassette system  100  includes a head rail  112 , two end brackets.  116  and two roller blinds (not shown, but identical to the roller blind of FIGS.  1 - 3 ). Each roller blind has its own set of end plugs  14 A,  14 B. One end plug of each roller blind is mounted on a leg  164  of one of the end brackets  116 . Importantly, the cassette system  100  further includes an intermediate bracket  117  arranged and constructed to slide within the longitudinal track formed by ribs  156 . The intermediate bracket  117  has a vertical member  160  and two legs  164 A and  164 B oriented in the opposite directions, as shown. These legs are used to support the other two end plugs of the roller blinds. In FIG. 4 a  the end plugs  14 B are shown mounted on the legs  164  while the end plugs  14 A are mounted on legs  164 A,  164 B. The positions of the end plug can be reversed, or an alternate arrangement can be used. For example, starting in FIG. 4 a , the leftmost end bracket can be used for an end plug  14 B, the intermediate bracket  117  could be used for one end plug  14 B (facing toward the left) and one end plug  14 B facing toward the right, The rightmost leg  164  could then be used for an end plug  14 A. 
     The scheme can be extended for any number of roller blinds. For this latter cassette system, two end brackets are required and a number of intermediate brackets, identical to bracket  117 , are used to provide the proper support. This cassette system has several advantages as well. First, the same type of parts are used for all systems, the only difference between systems being the length of the head rail  112 . A further advantage is that each roller blind can be raised and lowered independently. Finally, if individual cassette systems are used (whether identical to the system shown in FIGS. 1-3, or not) each system requires its own bracket and end cap at the interface between two adjacent systems. As a result, when the panels of each roller blinds are lowered, the horizontal spacing between these panels is substantial. Such a spacing may be esthetically undesirable. In the present invention, no end caps are required between roller blinds, and subsequently the horizontal spacing therebetween is substantially equal to the width of the intermediate bracket plus the width of the capstan  40 . (The distance by which the drum  34  on end plug  14 A extends axially beyond the roller  30  is negligible). 
     While the invention has been described with reference to several particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles of the invention. Accordingly, the embodiments described in particular should be considered as exemplary, not limiting, with respect to the following claims.

Summary:
A cassette system for window treatment includes a head rail with a base, end brackets attached to the base in a facing relationship and at least one roller blind with a mandrel and a decorative panel that is wound on the mandrel. The panel can be selectively drawn off the mandrel by rotation thereof. The end brackets are identical and mate with end plugs on the mandrel to rotationally support the roller blind. In an alternate embodiment, two or more roller blinds are supported by intermediate brackets or by an intermediate bracket and an end bracket. The end plugs on the madrel(s) have identical shapes to mate with respective legs on the end brackets.