US20030015301A1

US20030015301A1 - Motorized window shade system

Info

Publication number: US20030015301A1
Application number: US10/039,818
Authority: US
Inventors: Jason Killo; Joel Spira
Original assignee: Lutron Electronics Co Inc
Current assignee: Lutron Technology Co LLC
Priority date: 2001-07-19
Filing date: 2002-01-02
Publication date: 2003-01-23

Abstract

A quiet motorized window shade assembly mountable within a window frame includes a flexible shade and an elongated roller. An end of the shade is retained on the roller for winding of the shade on the roller. The window shade assembly further includes a drive system located externally of the roller. The drive system includes a motor and a drive shaft having a central axis parallel to a central axis of the roller. The drive shaft is connected to an acoustically lossy drive belt supported by drive and roller pulleys to transfer rotation of the drive shaft to rotation of the roller. The roller and drive belt substantially span a distance that separates opposing surfaces of the window frame to provide minimal distances between the window frame and the shade.

Description

CROSS REFERENCE TO RELATED APPLICATION

The present application claims the benefit of U.S. Provisional Application Serial No. 60/306,590, filed Jul. 19, 2001.[0001]

FIELD OF THE INVENTION

The present invention relates to a window shade system and, more particularly, to a window shade system having a motorized drive system providing minimum coverage gaps and quiet operation.

BACKGROUND OF THE INVENTION

Window shade systems having flexible shades supported by elongated rollers are well known. The roller is rotatably supported within a window frame for winding receipt of the flexible shade. Known shade systems include conventional manual shade roller systems having spring driven rollers and pawl mechanisms for releasably securing the roller against rotation. Jogging of the roller, by a user grasping the shade for example, releases the pawl mechanism to allow winding of the shade by the roller. Conventional manual shade rollers are relatively inexpensive and easy to install but may be subject to uncontrolled winding if a released roller is not restrained by a user.

Window shade systems having motor driven rollers are also known. Known systems include a drive motor supported between an end of the roller and the window frame to rotatingly drive the roller. Using a motor drive to rotate a shade roller offers advantages over conventional manual shade rollers including increased control over the winding and unwinding of a retained shade. The motor drive also facilitates more precise positioning of the roller shade in situations where only partial coverage of a window is desired.

Prior art motor drives for roller shades have a number of disadvantages including noise generated by the moving parts of the system and, in the case of externally mounted motor drives, increased gap between the edge of the shade and the window frame surface.

The rollers of known motorized shade systems are typically hollow tubes. It is known to provide a motor drive for a window shade roller having a motor housed within an end of the roller tube. The positioning of the drive motor internally of the roller reduces the space required between the roller and the frame, thereby increasing the maximum length of roller that may be supported in the frame. Increased roller length provides for wider shades and narrower coverage gaps. The hollow tube and attached flexible shade, however, act as a natural loudspeaker that amplifies the noise generated by the drive motor.

SUMMARY OF THE INVENTION

According to the present invention there is provided a quiet motorized window shade assembly for use within a window frame having opposing frame surfaces. The window shade assembly includes a flexible shade having opposite edges and an elongated roller having a central axis supported within the window frame. An end of the flexible shade is retained on a winding surface defined by the elongated roller for winding of the shade on the winding surface.

The motorized window shade assembly further includes a drive system located externally of the elongated roller having a motor and a drive shaft rotatably driven by the motor. The drive system is supported such that a drive shaft of the drive system is substantially parallel to the central axis of the roller. The window shade assembly also includes a drive belt supported at a first location to operably engage the drive shaft of the drive system. According to a preferred embodiment of the invention, the drive belt is supported at the first location by a drive pulley attached to the drive shaft of the drive system. The drive belt is also supported at a second location to operably engage the roller adjacent to the winding surface such that the rotation of the drive shaft results in rotation of the roller. According to the preferred embodiment of the invention, the drive belt is supported at the second location by a roller pulley secured to an end of the roller for rotation therewith.

The roller and the drive belt substantially span a distance that separates the opposing surfaces of the window frame so as to provide for minimal distance between the opposing surfaces of the window frame and the respective opposite edges of the shade.

According to a preferred embodiment, the drive belt is made from an acoustically lossy material to facilitate attenuation of vibrations in the drive system so as to reduce noise.

BRIEF DESCRIPTION OF THE DRAWINGS

For the purpose of illustrating the invention, there is shown in the drawings a form that is presently preferred; it being understood, however, that this invention is not limited to the precise arrangements and instrumentalities shown. [0011]
FIG. 1 is a front elevational view of a window shade system according to the present invention installed in a window frame; [0012]
FIG. 2 is an exploded perspective view of the drive end of the window shade system of FIG. 1; [0013]
FIG. 2A is an exploded perspective view of the drive unit of FIG. 2; [0014]
FIG. 3 is a perspective view illustrating the drive end of the window shade system of FIG. 1 being installed in the window frame; [0015]
FIG. 4 is an exploded perspective view of the idler end of the window shade system of FIG. 1 being installed in the window frame; [0016]
FIG. 5 is an exploded perspective view of a window shade system according to the present invention with the drive unit mounted in front of the shade; [0017]
FIG. 6 is an exploded perspective view of a window shade system according the present invention with the drive unit mounted between the shade and the window; and [0018]
FIG. 7 is an exploded perspective view of a window shade system according to the present invention having two motor driven rollers and an alternative pulley construction.[0019]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Referring to the drawings where like numerals refer to like elements, there is shown in FIG. 1 a [0020] window shade system 10 according to the present invention having a flexible shade 12 for covering a window pane 14 secured within a frame 16. The window frame 16 includes left and right upstanding side members 18, 20, respectively, and a top member 22 extending transversely between the side members. The window shade system 10 includes a drive end 24 secured to the frame 16 adjacent the intersection of left side member 18 and top member 22. The window shade system 10 further includes an idler end 26 secured adjacent an intersection of right side member 20 and top member 22 opposite the drive end 24. As will be described in greater detail, the window shade system 10 provides a motorized drive for raising and lowering the shade 12 that is quiet in normal operation while being compact in construction for limiting coverage gap between the shade 12 and the window frame 16.
Referring to FIG. 2, the construction of the [0021] window shade system 10, and in particular the construction of the drive end 24, can be seen in greater detail. An end of the flexible shade 12 is retained by a roller 28 for winding of the flexible shade 12 upon the roller 28. The attachment of the flexible shade 12 to the roller 28 is made in a conventional manner. The windable receipt of a flexible shade by an elongated roller is, per se, well known, and no further description is necessary. A portion of the flexible shade 12 has been removed from FIG. 1 to show an end 30 of the roller 28. It should be understood that the flexible shade 12 is preferably adapted to extend substantially the entire distance between opposite ends of the roller 28 to provide for maximum coverage and minimum coverage gap between the shade 12 and the frame 16. Depending on the direction in which roller 28 is rotated by drive unit 58 of drive end 24, to be described further, flexible shade 12 will alternatively be wound onto roller 28 as shown in FIG. 2 or unwound from roller 28 to cover window pane 14.
As shown in FIG. 2, the [0022] roller 28 comprises a tube defining a hollow interior. The drive end 24 of the window shade system 10 includes a drive coupler 32 having a surface 34 adapted for receipt within the end 30 of the roller 28. An annular ledge 36 is defined at an end of the coupler 32 that functions as a stop to limit the extent of the receipt of the coupler 32 within the roller 28. The coupler 32 is secured to end 30 of the roller 28 by screws 38 received by openings 40 in the roller 28 to engage the surface 34 of coupler 32.
The [0023] drive end 24 of the window shade system 10 further includes a drive transfer member comprising a roller pulley 42 having an annular belt-engaging portion 44 and a roller attachment post 46 extending from an end of the belt engaging portion 44. The roller attachment post 46 includes a torque transfer portion 48 at an end thereof for receipt within an opening 50 defined by the coupler 32. The torque transfer portion 48 of post 46 is adapted for engagement with a cooperatively formed surface of the opening 50 in the coupler 32 to transfer rotation between the roller pulley 42 and the coupler 32. The substantially hexagonal planar surfaces that are shown for the torque transfer portion 48, however, are not a requirement. Any cooperatively formed surfaces capable of transferring torque between the roller pulley 42 and the coupler 32 would be suitable.
The [0024] drive end 24 of the window shade system 10 further includes a drive belt 52 defining an endless loop. The belt engaging portion 44 of roller pulley 42 defines a channel in which the drive belt 52 is received (as shown in FIG. 3) to transfer movement of the drive belt 52 into rotation of the roller pulley 42. To facilitate the transfer between the drive belt 52 and the roller pulley 42, notches 54 are formed in the channel of the belt engaging portion 44 that are adapted for cooperative interfit with teeth 56 formed in the drive belt 52.
The [0025] drive end 24 of the window shade system 10 includes a drive unit 58 for driving the drive belt 52. As seen in the exploded perspective view of FIG. 2A, the drive unit 58 includes a reversible motor 60 and a worm gear right angle drive 62. The right angle drive includes a socket member 61 that alternatively may be referred to as a motor drive shaft. The motor 60 and right angle drive 62 are contained within a housing 64 having first and second portions 64A and 64B. The drive unit further includes a sub-housing 65 having a cover 67 for enclosing the worm gear right angle drive 62. The drive unit also includes a pair of mounting rings 69 for support of the motor 60 and right angle drive 62 within the housing 64. The worm gear right angle drive 62 functions to transfer rotation of the motor output to rotation of a further drive transfer member comprising a drive pulley 66. As will be described below, the drive pulley 66 is received by socket member 61 within the housing 64. The reversible motor 60 of the drive unit 58 is preferably a DC motor connectable to a standard wall receptacle through a low voltage transformer and motor control circuitry (not shown).
The construction of the [0026] drive unit 58 described above provides for substantial reduction in the noise that is generated by operation of the window shade system 10 compared to prior art window shade systems in which the drive unit is housed within the interior of the roller tube. The construction of a roller tube with an attached flexible shade causes the shade system to act as a natural loudspeaker amplifying the noise generated by the operation of the motor inside the roller tube. The belt drive system of the present invention provides for external positioning of the motor drive unit with respect to the roller, thereby eliminating the amplification of the motor noise by the roller tube and flexible shade.
The inclusion of [0027] drive belt 52 to transfer rotation from the drive unit 58 to the roller 28 also serves to reduce noise in comparison to that which would be generated if the output of an externally located drive unit was directly coupled to the end of the roller. The drive belt 52 functions to attenuate vibrations generated during rotational transfer between the drive unit and the roller tube. The attenuation of the vibrations associated with the rotational transfer results in reduction in noise generated by the drive system. To facilitate the vibration attenuation provided by the drive system, the drive belt 52 is preferably made of an acoustically lossy material such as nylon covered, fiberglass reinforced, neoprene.
The [0028] drive pulley 66 includes a belt engaging portion 68 and an integrally connected drive shaft 70 extending from an end of the belt engaging portion 68. The drive shaft 70 of the drive pulley 66 is received in an opening 72 of the drive unit housing 64 to engage the socket member 61 of the worm gear right angle drive 62. The drive shaft 70 has a surface adapted for torque transfer with the worm gear right angle drive 62 to facilitate driven rotation of the drive pulley 66 by the reversible motor 60 of the drive unit 58. The particular surface shown for the drive shaft is not a requirement and an alternative surface adapted for cooperative interfit with the worm gear right angle drive 62 would be sufficient. The drive shaft 70 of drive pulley 66 is received through an opening 76 in a bearing 74 that is also received within the housing 64 to facilitate rotation of the drive pulley 66 with respect to the drive unit 58. Similar to the roller pulley 42, the drive pulley 66 includes notches 78 formed on the belt engaging portion 68 to facilitate transfer of rotation of the drive pulley 66 into movement of the drive belt 52. Additionally, the cooperative engagement of the roller pulley notches 54 and the drive pulley notches 78 with the drive belt teeth 56 provides for accurate positional correlation between the roller 28 and the socket member 61. Non-slippage between the respective notches and teeth provides for accurate determination of positional information regarding shade 12 by a rotational position encoder 73. The position encoder 73 is housed within the motor 60 of drive unit 58 for determination of the rotational position of an output shaft of motor 60 (not shown). Determination of the rotational position of the output shaft of motor 60, in turn, provides for determination of the rotational position of the socket member 61. Rotational position encoders for sensing position of a drive shaft are well known and, therefore, require no further explanation.
The [0029] window shade system 10 includes a pulley guard 79 secured to the drive unit 58 to enclose the drive belt 52 and the pulleys 42, 66 as shown in FIG. 1. The window shade system 10 further includes a drive end mounting assembly 80 for securing the drive end 24 within the frame 16 such that the drive unit 58 is positioned substantially below the roller 28. As shown in FIG. 3, the mounting assembly 80 includes a drive end mounting bracket 82 secured to the left side member 18 of frame 16 by screws 84 received in openings 85. The mounting bracket 82 is secured to the frame 16 adjacent the intersection between the left side member 18 and the top member 22.
The drive [0030] end mounting assembly 80 further includes a drive unit mount 86 (FIG. 2) for securing the drive unit 58 to the mounting bracket 82. The drive unit mount 86 includes a drive unit attachment portion 88 and a bracket attachment portion 90. The drive unit attachment portion 88 of the drive unit mount 86 is secured to the drive unit 58 by screws 92 that extend through openings 94 in the drive unit attachment portion 88 to engage openings (not shown) in the drive unit housing 64. The bracket attachment portion 90 of the drive unit mount 86 includes a slot 98. Threaded stubs 100 (FIG. 3) extending from the mounting bracket 82 are received by slot 98. The drive unit mount 86 is secured to the mounting bracket 82 by nuts 102 threadedly engaging the stubs 100. The slot 98 of the bracket attachment portion 90 of drive unit mount 86 provides for adjustment in the relative position of the drive pulley 66 and the roller pulley 42.
The drive [0031] unit attachment portion 88 of the drive unit mount 86 is offset from the bracket attachment portion 90. The offset provides clearance between the mounting bracket 82 and the drive unit 58 to accommodate the belt engaging portion 68 of the drive pulley 66 and the drive belt 52. The drive unit attachment portion 88 of the drive unit mount 86 includes a notch 104 extending from an end of the drive unit mount 86. The notch 104 provides for extension of the drive shaft 70 of drive pulley 66 through the drive unit mount 86 to facilitate assembly of the drive end 24.
The drive [0032] end mounting bracket 82 further includes a roller support post 106 received by an opening 110 in a roller support bearing 108. The bearing 108 is, in turn, received within a central opening 112 defined in the roller pulley 42 for rotational support of the roller 28 by the drive end mounting bracket 82.
Referring now to FIG. 4, the construction of the [0033] idler end 26 of the window shade system 10 is shown. The idler end 26 includes an idler coupler 114 that is substantially similar in construction to the drive coupler 32. The idler coupler 114 includes a surface 116 adapted for receipt within an end of the tubular roller 28 opposite end 30. An annular ledge 118 is defined at an end of the idler coupler 1 14 to serve as a stop for the coupler. Similar to the drive coupler 32 of drive end 24, the idler coupler 114 is secured to the roller 28 by screws (not shown).
The [0034] idler end 26 includes an idler shaft 120 having a torque transfer portion 122 at one end and a support portion 124 at an opposite end. The idler shaft 120 is received within an idler coupling opening (not shown) of the idler coupler 114 in a similar manner to the drive coupler opening 50. Similar to the roller pulley 42 of drive end 24, the torque transfer portion 122 engages a cooperatively formed surface of the drive coupler opening to transfer rotation of the idler coupler 114 to rotation of the idler shaft 120.
The [0035] idler end 26 further includes a mounting bracket 126 secured to the top member 22 of frame 16 by screws 128. The mounting bracket 126 is secured to the frame 16 adjacent the intersection of top member 22 with right side member 20. The idler end 26 further includes a shaft support member 130 and a bracket attachment member 132. The bracket attachment member 132 is secured to the mounting bracket 126 by screws 134 received through slots 136 and notches 138 in the mounting bracket 126 to engage openings 140 in the bracket attachment member 132. The bracket attachment member 132 defines a ledge 142 and an elongated channel 144 for receipt of the shaft support member 130 by the bracket attachment member 132. The shaft support member 130 includes a base portion 146 supported on ledge 142 when the shaft support member 130 is received by the bracket attachment member 132. The shaft support member 130 also includes a shaft receiving portion 148 defining a pocket 150 providing rotatable support for the support portion 124 of idler shaft 120. The shaft receiving portion 148 includes a projection (not shown) opposite pocket 150 adapted for receipt by the channel 144 when the shaft support member 130 is received by the bracket attachment member 132. An adjustment mechanism (not shown) provides for adjustment of vertical position of the shaft support member 130 with respect to the bracket attachment member 132. The slots 136 and notches 138 provide for adjustment in the relative positioning between the bracket attachment member 132 and the mounting bracket 126 in a first perpendicular direction with respect to the elongated roller 28 that is oriented substantially horizontally in the view shown in FIG. 4. It should be understood that this construction, accordingly, also provides for adjustment of the position of the idler shaft 120 and roller 28 in the first perpendicular direction. Using separate shaft support member 130, bracket attachment member 132 and mounting bracket 126 facilitates ease of installation by enabling adjustment of the roller position after installation.
The construction of the [0036] window shade system 10, in particular drive end 24, according to the present invention provides for minimization of coverage gap between the flexible shade 12 and the frame 16. The minimization of coverage gap is provided by the lateral offset between the central axis of the rotational output from the drive unit 58 and the central axis of the roller 28. The lateral offset allows for a relatively longer roller extending between the left and right frame members 18, 20, than would be possible were an external drive unit to be directly coupled to the end of the roller 28. The relatively longer roller 28, accordingly provides for a relatively wider roller shade 12 supported by the roller 28.
Referring to FIG. 1, a first [0037] minimal coverage gap 152 is defined between one of the edges of the shade 12 and left side member 18 of frame 16. A second minimal coverage gap 154 is defined between an opposite edge of shade 12 and the right side member 20 of frame 16. As may be seen, the width of the coverage gap 152 at the drive end 24 will depend largely on the width of the drive pulley 42, which, in turn, depends largely on the width of the drive belt 52. It is important to note that the width of the coverage gap 152 is completely independent of the drive unit 58. Therefore, variations in the size and configuration of the drive unit 58 will have no effect on the minimal coverage gap achievable by the window shade system 10. A minimal coverage gap 152 having a width as small as about one inch, plus or minus one eighth of an inch, is achievable with a drive belt 52 having a width of approximately 9 mm (0.354 inches).
Referring to FIG. 5, there is shown an alternative [0038] window shade system 156 according to the present invention. The window shade system 156 includes a drive end 158 secured to right side member 162 of a frame 160 as opposed to a left side frame member as was the case with drive end 24 of window shade system 10. The drive end 158 is supported within the frame 160 to position a drive unit 161 substantially in front of the roller 28 rather than substantially below the roller 28 as was the case for drive end 24 of window shade system 10. The drive end includes a mounting bracket 164 that is identical in construction to mounting bracket 82 of window shade system 10. To position the drive unit 161 in front of roller 28, the mounting bracket 164 is secured within frame 160 by screws 165 in an orientation perpendicular to the orientation of mounting bracket 82 such that bracket 164 extends toward a window pane 166. This allows shade 12 to be located relatively closely to the window pane 166.
The [0039] drive end 158 includes a drive unit mount 168 having a slot 170 for receipt of the drive unit mount 168 on threaded stubs 172 of mounting bracket 164. The drive unit mount 168 is secured to the mounting bracket 164 by nuts 174. The drive unit mount 168 is identical in construction to drive unit mount 86 of window shade system 10 and includes openings 176 for securing drive unit 161 to the drive unit mount 168 by screws (not shown). It should be noted that the openings 176 in drive unit mount 86 are arranged in a substantially square pattern. This arrangement provides for attachment of drive unit 161 to drive unit mount 168 in at least two different orientations that are perpendicular to one another. As shown in FIG. 5, this provides for a substantially vertical orientation for drive unit 161.
Referring to FIG. 6, there is shown an alternative [0040] window shade system 180 according to the present invention. The window shade system 180 includes a drive end 182 secured to a left side member 186 of a frame 184 such that a drive unit 188 of the drive end 182 is positioned between the shade 12 and a window pane 190. The drive end 182 includes a mounting bracket 192 identical in construction to mounting bracket 82 of window shade system 10. To position the drive unit 188 between the shade 12 and the window pane 190, the mounting bracket 192 is secured within frame 184 by screws 194 in an orientation perpendicular to the orientation of mounting bracket 82 such that mounting bracket 192 extends toward window pane 190. The drive end 182 includes a drive unit mount 196 identical in construction to the drive unit mount 86. The drive unit mount 196 includes a slot 198 for receipt of the drive unit mount 196 on threaded stubs 200 of mounting bracket 192. The drive unit mount 196 is secured to the mounting bracket 192 by nuts 202. Similar to the drive unit mount 168 of FIG. 5, the drive unit mount 196 includes openings 204 that provide for mounting of the drive unit 188 in a substantially vertical orientation as shown in FIG. 6.
Referring to FIG. 7, there is shown a [0041] window shade system 206 according to the present invention that provides for motor driven support of two roller shades. The window shade system 206 includes a pair of drive ends 208 each including a drive unit 58 for driving a rotatably supported roller 210. The window shade system 206 includes a mounting bracket 212 for securing the drive ends 208 to the left side member 216 of a frame 214. The mounting bracket 212 is wider than mounting bracket 82 for window shade system 10 to accommodate two drive ends 208. The mounting bracket 212 also includes two roller support posts 218, identical to support post 106 of window shade system 10, for supporting two roller pulleys 220. Each of the drive units 58 rotationally drives a drive pulley 222. The opposite end (not shown) of the window shade system 206 will include a pair of idler ends each preferably identical in construction and support to the idler end 26 of window shade system 10.
Each of the drive ends [0042] 208, with the exception of the roller pulleys 220 and drive pulleys 222, is substantially similar in construction to the drive end 24 of window shade system 10 described above. The roller pulleys 220 and drive pulley 222 have been modified from the roller pulley 42 and drive pulley 66 of window shade system 10 to achieve an increase in the relative rotational speed of the roller pulley 220 with respect to the drive pulley 222. As shown, a belt engaging portion 224 of the roller pulley 220 has a reduced diameter with respect to the belt engaging portion 44 of roller pulley 42. Further, a belt engaging portion 226 of drive pulley 222 has an increased diameter with respect to the belt engaging portion 68 of drive pulley 66. The relatively small size of the roller pulley 220 compared to the size of the drive pulley 222 results in a step-up in rotational speed such that the rotational speed of the roller pulley 220 is increased with respect to that of the drive pulley 222. For clarity of view, only one of the drive belts 52 is shown, that being the drive belt 52 connecting the pair of pulleys 222, 220 furthest from the window. A similar drive belt 52 (not shown) connects the pair of pulleys 222, 220 nearest the window.
The step-up in rotational speed provided by [0043] pulleys 220, 222 allows for a reduction in the output rotational speed necessary for drive units 58 of window shade system 206 to achieve the same roller rotational speed generated by the drive end 24 of window shade system 10. Such a reduction, or step down, in the required output speed for the drive unit accordingly provides for a quieter drive unit 58 for the drive ends 208. It should be understood that it is not required that both the roller pulley 220 and the drive pulley 222 be modified in order to achieve a step down in rotational speed of the drive unit 58. Either an increase in the diameter of the drive pulley 222, or a decrease in the diameter of the roller pulley 220, would produce a step up in rotational speed between the drive pulley 222 and the roller pulley 220.
Alternatively, the drive ends [0044] 208 of FIG. 7 could be located at opposite ends of the respective roller shades such that one drive end 208 is attached to the left side member 216 of the frame 214 and the other drive end 208 is attached to the right side member (not shown) of frame 214.
While the present invention has been described in connection with the preferred embodiments of the various figures, it is to be understood that other similar embodiments may be used or modifications and additions may be made to the described embodiment for performing the same function of the present invention without deviating therefrom. Therefore, the present invention should not be limited to any single embodiment, but rather should be construed in breadth and scope in accordance with the recitation of the appended claims. [0045]

Claims

What is claimed is:

1. A motorized shade assembly for use within a window frame having opposing frame surfaces, the shade assembly comprising:

a flexible shade having opposite edges;

an elongated roller having a central axis and supported within the window frame for rotation about the central axis, the roller defining a winding surface and retaining an end of the flexible shade for winding receipt of the shade;

a drive system located externally of said elongated roller and having a motor and a drive shaft rotatably driven by the motor, said drive shaft having a central axis, the drive system supported adjacent an end of the elongated roller such that the central axis of the drive shaft is substantially parallel to the central axis of the roller; and

a drive belt defining an endless loop, the drive belt supported at a first location to operably engage the drive shaft of the drive system and at a second location to operably engage the roller adjacent the winding surface such that the rotation of the drive shaft results in rotation of the roller,

the roller and drive belt substantially spanning the distance between the opposing surfaces of the window frame to provide for minimal distance between the opposing surfaces of the window frame and the respective opposite edges of the flexible shade.

2. The motorized shade assembly according to claim 1 wherein the minimal distance is independent of the size of the drive system.

3. The motorized shade assembly according to claim 1 wherein the minimal distance at the drive system end of the elongated roller is less than about 1 inch between the window frame surface and the respective flexible shade edge.

4. The motorized shade assembly according to claim 1, further comprising a first drive transfer member supported for rotation about a central axis, the drive transfer member coupled to the roller for coaxial rotation therewith, the drive belt engaging the drive transfer member to transfer rotation of the drive motor shaft to rotation of the roller.

5. The motorized shade assembly according to claim 4, wherein the drive transfer member comprises a cylindrical portion defining an outer surface adapted for engagement with an inner surface of the drive belt.

6. The motorized shade assembly according to claim 5, wherein the drive transfer member further comprises a post extending from the cylindrical portion, the post having an outer surface adapted for interfit within an opening in a drive coupler secured to the roller, the interfit between the post and the opening providing for torque transfer between the first drive transfer member and the roller.

7. The motorized shade assembly according to claim 5, wherein the outer surface of the cylindrical portion of the first drive transfer member includes spaced notches, and wherein the inner surface of the drive belt includes spaced teeth, the spacing of the drive belt teeth being substantially equal to the spacing of the notches of the first drive transfer member to facilitate engagement therebetween.

8. The motorized shade assembly according to claim 4, further comprising a second drive transfer member having a central axis, the second drive transfer member secured to the drive shaft for coaxial rotation therewith, the drive belt engaging the second drive transfer member to transfer rotation of the drive shaft to rotation of the elongated roller.

9. The motorized shade assembly according to claim 7, further comprising a second drive transfer member having a central axis, the second drive member secured to the drive shaft for coaxial rotation therewith, the second drive transfer member comprising a cylindrical portion having a notched outer surface, the notches of the second drive transfer member having a spacing that is substantially equal to the spacing of the drive belt teeth to facilitate engagement therebetween.

10. A window shade drive assembly for use within a window frame having opposing frame surfaces, the window shade drive assembly comprising:

an elongated roller supported for rotation about a central axis and adapted for winding and unwinding a flexible shade having opposite edges upon rotation of the roller;

a drive system located externally of said elongated roller having a motor and a drive shaft rotatably driven by said motor, said drive shaft having a central axis, the drive system supported such that the drive shaft central axis is substantially parallel to the roller central axis;

a drive belt operably connected to the drive shaft such that the drive belt is driven by the drive shaft; and

a first drive transfer member having a central axis, the first drive transfer member coupled to an end of the elongated roller for coaxial rotation therewith,

the elongated roller and the first drive transfer member extending between opposing frame surfaces of the window frame and substantially spanning a distance therebetween to provide for minimization of the size of the gaps between the opposing surfaces of the window frame and the respective opposite edges of a shade supported by the roller.

11. The motorized shade assembly according to claim 10 wherein the sizes of the gaps are independent of the size of the drive system.

12. The motorized shade assembly according to claim 10 wherein the sizes of the gaps are less than about 1 inch.

13. The window shade drive assembly according to claim 10, further comprising a second drive transfer member having a central axis, the second drive transfer member secured to the drive shaft for rotation therewith, the drive belt engaging the second drive transfer member to be driven thereby.

14. The window shade drive assembly according to claim 13, wherein each of the first and second drive transfer members includes a substantially cylindrical member defining an outer surface that engages an inner surface of the drive belt to transfer rotation of the drive shaft to rotation of the elongated roller.

15. The window shade drive assembly according to claim 14, wherein the outer surface of the first drive transfer member has a diameter that is less than a diameter of the outer surface of the second drive transfer member, the difference in the diameters providing for decreased rotational speed for the drive shaft for a given rotational speed for the roller thereby reducing noise.

16. The window shade drive assembly according to claim 14, comprising first and second elongated rollers each having a central axis, the central axis of the second elongated roller offset from the central axis of the first elongated roller to provide for support of inner and outer shades with respect to the frame of the window.

17. The window shade drive assembly according to claim 16, wherein the first and second elongated rollers are positioned between opposing first and second frame surfaces of the window frame, the drive assembly comprising first and second drive systems for driving the first and second elongated rollers, respectively, and wherein the first drive system is adapted for support adjacent the first frame surface and the second drive system is adapted for support adjacent the second frame surface.

18. A motor driven shade assembly for use within a window frame having opposing frame surfaces, the motor driven shade assembly comprising:

a flexible shade having opposite edges;

an elongated roller supported for rotation about a central axis, the elongated roller adapted for winding receipt of the flexible shade;

a drive transfer member having a central axis, the drive transfer member coupled to an end of the elongated roller to provide for torque transfer from the drive transfer member to the elongated roller; and

a flexible drive belt engaging an outer surface of the drive transfer member to transfer rotation to the roller from a drive shaft having a central axis that is offset from the roller central axis,

the roller and drive transfer member extending between the opposing frame surfaces of the window frame and substantially spanning the distance therebetween to minimize the distance between the opposite shade edges and the respective opposing surfaces of the window frame.

19. A motor driven shade assembly for use with a flexible shade comprising:

a drive transfer member having a central axis, the drive transfer member coupled to an end of the elongated roller to provide for torque transfer from the drive transfer member to the elongated roller;

a drive system having a motor and a drive shaft, said drive shaft having a central axis that is offset from the roller central axis; and

a flexible drive belt engaging an outer surface of the drive transfer member to transfer rotation to the roller from the drive shaft,

the flexible drive belt being made of an acoustically lossy material such that noise transmitted from the drive system to the elongated roller shade is reduced below that which would occur if the motor drive system was directly coupled to the elongated roller.

20. A motor driven shade system for use with a flexible shade comprising:

a drive system having a motor extending along a long axis of said drive system, a right angle drive and a drive shaft having a central axis that is offset from the roller central axis; and

thereby allowing the long axis of the drive system to be mounted perpendicular to the elongated roller.

21. The motor driven shade system according to claim 20 wherein the right angle drive is a worm gear drive.

22. The motor driven shade system according to claim 20 wherein said motor driven shade system is adapted for use in a window frame having opposing vertical surfaces and wherein said long axis of said drive system is parallel to one of said opposing vertical surfaces.

23. A motor driven shade system for use with a flexible shade comprising:

an elongated roller supported for rotation about a central axis, said elongated roller adapted for winding receipt of said flexible shade;

a first drive transfer member having a central axis, said first drive transfer member coupled to an end of said elongated roller to provide for torque transfer from said first drive transfer member to said elongated roller, said first drive transfer member having notches arranged peripherally around its circumference;

a drive system having a motor coupled to a drive shaft, said drive shaft having a central axis that is offset from said roller central axis, a second drive transfer member coupled to said drive shaft for rotation therewith, said second drive transfer member having notches arranged peripherally around its circumference, and a drive shaft rotational position detector operatively coupled to provide rotational position information of said drive shaft; and

a flexible drive belt having teeth, said teeth engaging said notches of said first and second drive transfer members to transfer rotation to said roller from said drive shaft, thereby preventing slippage between said first and second drive transfer members and said flexible belt drive such that said drive shaft rotational positional detector can determine the rotational position of said elongated roller.