SHADE LIFTING MECHANISM

Abstract

A window covering positioning system including a tube to facilitate raising and lowering of a window covering. The system further includes a rotational drive mechanism attached to the tube to drive rotation of the tube about an axis of the tube and an axial drive mechanism connected to the tube to drive movement of the tube in an axial direction. The axial drive mechanism is circumferentially disposed within the tube. A kit is further provided. The kit includes a tube around which a cord of a window covering is positioned and a rotational drive mechanism to rotate the tube about an axis of the tube. The kit further includes an axial drive mechanism to advance the tube in an axial direction and a connector to rotatably connect the tube to the axial drive mechanism.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority from U.S. Provisional Patent Application Ser. No. 60/911,053, filed on Apr. 10, 2007, which is incorporated herein by reference in its entirety.

BACKGROUND

1. Field

Mechanisms for raising and lowering window coverings. More specifically, mechanisms for raising and lowering window coverings without overlapping coils of the window covering cords.

2. Background

Window coverings play a dual role for the customer. On the one hand, they block light from coming through during the day. On the other hand, they provide privacy during the night. One type of covering typically used to block light is a roller shade because it is simple and functional. Roller shades, however, are typically not very decorative. Another type of window covering is a folding shade. Folding shades are made in many different styles and decorative materials can be used to achieve a desired appearance. Venetian blinds and mini blinds having horizontal slats which can be rotated to open the blind while the blind is still covering the window are another example of a window covering.

Hanging window coverings such as roller shades, folding shades, Venetian and mini blinds may be raised and lowered in many different ways. The coverings are typically equipped with lifting cords attached to the bottom of the covering which may be pulled up or let loose to raise or lower the shade. In some cases a lifting mechanism, commonly referred to as a cord locking mechanism, is used to control the positioning of the lifting cords. The cord locking mechanism utilizes a cord lock housing through which the lifting cords pass. The cord lock holds the cords in place thereby keeping the shade in a desired position until the cords are pulled to one side to release the lock. The cord locking mechanism is useful for small and medium size shades, but is not very functional for larger shades. In addition, the cord locking mechanism does not provide any mechanical advantage and significant forces are required to lift larger shades.

Another technique for lifting a shade uses a rolling mechanism. In this technique, the lifting cords are usually rolled up on a tube or a rod. A clutch attached to the end of the tube is rotated by pulling on a main lift cord, for example a bead chain, inserted into a sprocket of the clutch. Lifting cords attached to the tube rotate around the tube to either raise or lower the shade. Conventional rolling mechanisms, however, have many disadvantages. In particular, lifting cords will roll on top of each other eventually causing the shade to be lifted or lowered unevenly. In addition, when the cords roll up on top of each other they may cause one side of the shade to lift faster than the other. In rolling mechanisms where the cords initially roll up in a spiral fashion, the portions of the cords being rolled around the tube shift in relation to the shade thereby pulling the shade from side to side. In this aspect, the shade will slide to one side of the window leaving the other side with an undesirable gap.

BRIEF DESCRIPTION OF THE DRAWINGS

The embodiments herein are illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one.

FIG. 1 is a perspective view of a window covering positioning mechanism.

FIG. 2 is a cross sectional view of a window covering positioning mechanism along line A of FIG. 1.

FIG. 3 is a cross sectional view of a window covering positioning mechanism along line B of FIG. 1.

FIG. 4 is a front view of a window covering positioning mechanism with a window covering in a lowered position.

FIG. 5 is a front view of the window covering positioning mechanism of FIG. 4 with the window covering in a raised position.

FIG. 6 is a back view of the window covering positioning mechanism of FIG. 5 with the window covering in the raised position.

FIG. 7 is a perspective view of a back side of a window covering positioning mechanism with a window covering in a lowered position.

FIG. 8 is a perspective view of a back side of a window covering positioning mechanism with a window covering in a raised position.

FIG. 9 is a flow chart of a method for assembling a window covering positioning mechanism.

DETAILED DESCRIPTION

FIG. 1 is a perspective view of a window covering positioning mechanism. Rotational drive mechanism 104 and axial drive mechanism 106 may be connected to tube 102 to drive movement of tube 102. Movement of tube 102 in turn raises or lowers a window covering attached to tube 102 via cords 122a and 122b. Tube 102 may be of any size and be made of any material suitable for supporting a desired window covering. In some embodiments, tube 102 may be made of a plastic or metal material. Tube 102 may be hollow such that components of window covering positioning mechanism 100 may be positioned within tube 102. In this aspect, a portion of tube 102 is shown removed in FIG. 1 to illustrate features of rotational drive mechanism 104 and axial drive mechanism 106 positioned therein.

Rotational drive mechanism 104 may be connected to tube 102 at its end and rotate tube 102 about its longitudinal axis. Rotation of tube 102 causes cords 122a and 122b to either coil around tube 102 or uncoil from tube 102 depending upon the direction of tube 102 rotation.

Upon rotation of tube 102 by rotational drive mechanism 104, axial drive mechanism 106 causes tube 102 to advance in an axial direction. Thus, as tube 102 rotates it also slides away from or toward rotational drive mechanism 104. Cords 122a and 122b coiled around tube 102 move from side to side along with tube 102. A vertical position of the portion of cords 122a and 122b not yet coiled around tube 102, however, is maintained in the same place relative to rotational drive mechanism 104. In this aspect, each coil of cords 122a and 122b may be wrapped around tube 102 one next to another with the vertical position of cords 122a and 122b maintained in the same place. Since the coils of each of cords 122a and 122b do not roll up on top of one another and the portion of cords 122a and 122b extending from tube 102 to an end of the window covering do not change their vertical positions, the window covering may be raised in a uniform manner and without undesirable shifting of the window covering from side to side.

In some embodiments, rotational drive mechanism 104 may be a clutch mechanism. In still further embodiments, rotational drive mechanism 104 may be a tubular motor, spring motor or any other similarly suitable mechanism for driving rotation of tube 102. A rotatable housing 112 may extend from a surface of rotational drive mechanism 104. Housing 112 may be a substantially cylindrical structure positioned around a pulley 304 (see FIG. 3) of rotational drive mechanism 104. Pulling on main cord 144 (e.g. bead chain) positioned within a sprocket of pulley 304, rotates pulley 304 and in turn rotates housing 112. Components of rotational drive mechanism 104, for example, pulley 304 and housing 112, may be made of any material suitable for driving rotation of tube 102. Representative suitable materials may include, but are not limited to, metals and plastics.

Housing 112 may be positioned within an end portion of tube 102. In this aspect, housing 112 may have an outer diameter slightly smaller than an inner diameter of tube 102. Housing 112 and tube 102 may have complimentary surface dimensions such that housing 112 engages tube 102 upon rotation and causes rotation of tube 102. In some embodiments, the complimentary dimensions may include key 116 extending from an inner surface of tube 102 and receiving groove 114 formed along an outer surface of housing 112. Key 116 is a protrusion extending inwardly from an inner surface of tube 102. Key 116 catches in groove 114 when housing 112 rotates causing rotation of tube 102 in the same direction as housing 112. Groove 114 is slightly larger than key 116 to ensure ease of engagement of these two components. Key 116 and groove 114 may further be dimensioned to allow key 116 to slide from side to side within groove 114 when tube 102 is advanced in the axial direction. For example, in some embodiments, groove 114 may have a width of 0.300 inches and a depth of 0.125 inches while key 116 has a width of 0.280 inches and a height of 0.100 inches.

Although a key and groove type engagement mechanism between tube 102 and housing 112 is described, it is contemplated that any other similarly suitable engagement mechanism may be used to attach tube 102 to housing 112 during rotation of housing 112. Representatively, in some embodiments a slot may be cut out of tube 102 and a dowel pin fixedly attached to housing 112 may slide inside the slot.

Axial drive mechanism 106 may extend from a stationary base member of rotational drive mechanism 104 to drive movement of tube 102 in an axial direction. Representatively, where rotational drive mechanism 104 is a clutch mechanism, axial drive mechanism 106 may be fixedly secured to stationary base member 110 of the clutch mechanism. Alternatively, axial drive mechanism 106 may be fixedly secured to a stationary bracket 138 positioned at an end of tube 102. It is contemplated that in some embodiments, stationary bracket 138 may be integrally formed with base member 110 to form the stationary component. Axial drive mechanism 106 may be secured to the stationary component by, for example, screws, bolts, clips or any other similarly suitable securing mechanism.

In some embodiments, axial drive mechanism 106 may be a cylindrical shaft, such as a screw, circumferentially disposed within tube 102 and housing 112. Representatively, axial drive mechanism 106 may extend from stationary base member 110 through housing 112 and beyond an end of housing 112. In this aspect, an outer diameter of axial drive mechanism 106 may be smaller than an inner diameter of housing 112. Representatively, in some embodiments, a diameter of axial drive mechanism 106 may be Ø 0.290 inches.

Cylindrical connector 118 may be fixedly secured to an inner surface of tube 102 and positioned around axial drive mechanism 106. Helical threading 108 may be formed around an outer surface of axial drive mechanism 106. Connector 118 may in turn have complimentary threading to that of axial drive mechanism 106. Rotation of tube 102 as previously described rotates connector 118 which in turn causes connector 118 to follow threading 108 of axial drive mechanism 106. This in turn forces tube 102 to follow threading 108 and advance along axial drive mechanism 106 in an axial direction. Tube 102 may be advanced in a direction toward or away from rotational drive mechanism 104 depending upon the direction rotational drive mechanism 104 rotates tube 102.

Axial drive mechanism 106 may be dimensioned to advance tube 102 a specific distance with every rotation of tube 102. In some embodiments, the distance may be equal to a diameter of cords 122a and 122b attached to tube 102. In this aspect, each coil of cords 122a and 122b may be positioned next to the previously wound coil to prevent overlapping of cords 122a and 122b.

In one embodiment, the desired advancement distance may be achieved by modifying a pitch of helical threading 108 of axial drive mechanism 106. The term “pitch” as used herein refers to the distance between two adjacent threads. Representatively, where a diameter of the lifting cord is 0.052 inches, the pitch of helical threading 108 on axial drive mechanism 106 may be 0.056 inches. In this aspect, tube 102 will move 0.056 inches in the axial direction with each complete rotation of tube 102.

Connector 118 may be secured to tube 102 with screw 120 or any other similarly suitable securing mechanism such as a bolt, clip or pin. Alternatively, connector 118 may be integrally formed from or molded along an inner surface of tube 102. Axial drive mechanism 106 and connector 118 may be made of any material suitable for driving movement of tube 102. Representative suitable materials, may include, but are not limited to, a plastic or metal material.

In some embodiments, cord clips 124a and 124b may be attached to an outer surface of tube 102 to secure an end of cords 122a and 122b to tube 102. In some embodiments, cord clip 124a may have body portion 126a and base portion 128a. Cord clip 124b may further have body portion 126b and base portion 128b. Securing arms 146a and 146b for holding cords 122a and 122b, respectively, may extend from body portions 126a and 126b. Securing arms 146a and 146b may be, for example, clamps designed to clamp onto an end of cords 122a and 122b, respectively. Alternatively, securing arms 146a and 146b may be ring like structures having an opening through which the end of cords 122a and 122b, respectively, may be inserted and then tied to itself or the ring.

Cord clips 124a and 124b may be secured to tube 102 by inserting them within channel 148 formed along an outer surface of tube 102. In this aspect, base portions 128a and 128b may have shapes complimentary to a curvature of the outer surface of tube 102. A protrusion (not shown) may extend from each of base portions 128a and 128b. The protrusion may be dimensioned to fit within channel 148. In some embodiments, channel 148 may be formed along a portion of tube 102 opposite key 116. In some embodiments, cord clips 124a and 124b are removeably positioned within channel 148 to facilitate easy removal or readjustment of cord clips 124a and 124b. Cord clips 124a and 124b may be made of any material suitable for securing cords 122a and 122b to tube 102. Representatively, cord clips 124a and 124b may be made of a plastic, metal or rubber material.

Although two cord clips 124a and 124b are illustrated, the number of cord clips may vary depending upon the number of cords. Representatively, two cords 122a and 122b are illustrated in FIG. 1 therefore two cord clips 124a and 124b are used. The number of cords may vary depending upon the size and/or material of the window covering. Representatively, as a width of the window covering increases, more than two cords may be necessary to support and lift the window covering. In addition, window coverings made of heavier materials, such as wood as opposed to fabric or plastic may require more than two lifting cords to support and lift the window covering.

Shade covering positioning mechanism 100 may further include hardware to support components of mechanism 100. The hardware may include bracket 138 connected to rotational drive mechanism 104. Bracket 138 may be removeably attached to stationary base member 110 of rotational drive mechanism 104. For example, stationary base member 110 may be screwed or clipped to bracket 138. It is further contemplated that in some embodiments, bracket 138 may be integrally formed with stationary base member 110 of rotational drive mechanism 104.

Brackets 130a and 130b may further be provided to support tube 102. Each of brackets 130a and 130b may include bushing member 132a and 132b, respectively. Bushing members 132a and 132b may be positioned around tube 102. Bushing members 132a and 132b may have an inner diameter slightly larger than an outer diameter of tube 102 so that tube 102 may be easily rotated within bushing members 132a and 132b. Although two brackets 130a and 130b are illustrated in FIG. 1, it is contemplated that more than two or less than two brackets may be used depending upon the length of tube 102. Tube 102 may be secured to brackets 130a and 130b by inserting bushing members 132a and 132b over an end of tube 102 and then moving bushing members 132a and 132b along tube 102 until a desired position is reached.

Brackets 130a, 130b and 138 may be removeably secured to aligning rail 140. Aligning rail 140 may in turn be mounted to a structure above a window to secure the entire window covering assembly in front of the window. Aligning rail 140 may include channels 142 to receive bracket arms 608a, 608b and 606 (see FIG. 6) extending from ends of brackets 130a, 130b and 138, respectively. To secure brackets 130a, 130b and 138 to aligning rail 140, bracket arms 608a, 608b and 606 may be inserted into ends of channels 142 formed at the edge of aligning rail 140 and then slid along aligning rail 140 until a desired position is reached. Brackets 130a, 130b, 138 and aligning rail 140 may be made of any material suitable for supporting a window covering. Representative suitable materials, may include, but are not limited to, a plastic or metal material.

In some embodiments, window covering positioning mechanism 100 further includes a pair of stop rings 134a and 134b to limit rotation and advancement of tube 102. Stop rings 134a and 134b are substantially cylindrical structures positioned around tube 102. Stop rings 134a and 134b may be fixedly attached to tube 102 by, for example, screw 136. Alternatively, stop rings 134a and 134b may have a protrusion similar to that of cord clips 124a and 124b extending from an inner surface which may be inserted into channel 148 to hold stop rings 134a and 134b in place. As will be described in more detail in reference to FIG. 6, stop rings 134a and 134b may have a shoulder 602 extending from an edge adjacent brackets 130a and 130b, respectively. Brackets 130a and 130b may in turn have oppositely positioned shoulders 604 extending from edges of bushing members 132a and 132b which catch on the shoulders of stop rings 134a and 134b to stop rotation and advancement of tube 102. In this aspect, lower and upper lifting limits may be set for window covering positioning mechanism 100.

For example, a lower limit (i.e. furthest distance the window covering may be lowered) may be set by positioning stop ring 134a at a position along tube 102 such that the shoulder of stop ring 134a and the shoulder of bushing member 134a engage one another as shown in FIG. 1 when the window covering is in the lowest desired position (i.e. a closed position). An upper lifting limit (i.e. the furthest distance the window covering may be raised) may be set by positioning stop ring 134b at a position along tube 102 such that the shoulder of stop ring 134b and the shoulder of bushing member 132b engage one another when the window covering is in the highest desired position (i.e. an open position). In some embodiments, the upper lifting limit may be set so that the window covering does not contact tube 102 or other components of the assembly which could damage the window covering upon repeated contact. In addition, a consideration of the length of axial drive mechanism 106 may be taken into account when setting the upper lifting limit. Representatively, stop ring 134b may be positioned so that advancement of tube 102 is stopped before connector 108 reaches an end of axial drive mechanism 106. In still further embodiments, the lower lifting limit may be set so that lowering of the window covering is stopped once the window covering reaches a bottom of the window.

FIG. 2 is a cross sectional view of a window covering positioning mechanism along line A of FIG. 1. Connector 118 is shown positioned around axial drive mechanism 106. Connector 118 rotates about axial drive mechanism 106 as previously discussed. Tube 102 is fixedly secured along a surface of connector 118 opposite axial drive mechanism 106. In the embodiment illustrated in FIG. 2, screw 120 is used to secure tube 102 to connector 118. In this aspect, as tube 102 rotates, connector 118 in turn rotates and follows the helical threading around axial drive mechanism 106 to advance tube 102 in the axial direction.

Channel 148 is formed within tube 102. In some embodiments, channel 148 is formed in a portion of tube 102 opposite screw 120. Retaining arms 202a and 202b may extend partially across an opening of channel 148 to retain a cord clip therein. Representatively, as previously discussed, the cord clip, for example cord clip 124a, may have a protrusion extending from its base. The protrusion of cord clip 124a may be a substantially “T” shaped structure such that once the protrusion is positioned within channel 148, the end, bar portion of the protrusion catches on retaining arms 202a and 202b and is held therein. In this aspect, the bar portion of the protrusion may be flexible so that the protrusion may be deformed during insertion of the protrusion into channel 148 and then reform to its original shape. Alternatively, retaining arms 202a and 202b may be flexible. In other embodiments, retaining arms 202a and 202b and the protrusion may be made of an inflexible material and snap fit together. In still further embodiments, the protrusion of cord clip 124a may be inserted into the opening of channel 148 found at the end of tube 102 and slid along channel 148 until the desired positioned is reached. Regardless of the manner in which cord clip 124a is secured to channel 148, clip 124a is dimensioned to snugly within channel 148 to prevent sliding of cord clip 124a and in turn cord 122a attached thereto along tube 102. Although cord clip 124a is described above, it is contemplated that the description further applies to cord clip 124b.

FIG. 3 is a cross sectional view of a window covering positioning mechanism along line B of FIG. 1. In this embodiment, axial drive mechanism 106 is shown positioned within an opening of pulley 304 of rotational drive mechanism 104. Pulley 304 includes one or more of drive edge 306. Drive edge 306 catches on an edge of groove 114 extending from an inner surface of housing 112 when pulley 304 is rotated to cause rotation of housing 112.

In some embodiments, sleeve 302 may be positioned along an end portion of tube 102 proximal to rotational drive mechanism 104. Sleeve 302 protects an end of tube 102 from wear and tear that may result due to contact of tube 102 and rotational drive mechanism 104. Sleeve 302 may be a cylindrical member having a rim extending from its edge. The cylindrical portion of sleeve 302 may be inserted within tube 102 and the rim may extend from the cylindrical portion over an edge of tube 102. The rim may have a length equal to a thickness of tube 102 so as not to extend beyond an outer surface of tube 102.

The cylindrical portion of sleeve 302 may have an outer diameter slightly smaller than an inner diameter of tube 102 such that it snugly fits within an end of tube 102 and is held therein. In some embodiments, sleeve 302 may be made of an elastomeric material such as rubber that conforms to the dimensions of the inner surface of tube 102. Alternatively, sleeve 302 may be made of any plastic or metal material suitable for protecting an end of tube 102. In some embodiments, an adhesive or other securing mechanism such as a screw or clip may be used to hold sleeve 302 within tube 102.

Housing 112 and tube 102 may be symmetrical about their axes. In this aspect, housing 112 includes a second groove formed opposite to groove 114 and tube 102 includes a second key formed opposite to key 116 to fit within the second groove as illustrated in FIG. 3. Tube 102 further includes a second channel formed opposite to channel 148 having retaining arms 202.

FIG. 4 is a front view of the window covering positioning mechanism with a window covering in a lowered position (i.e. closed position). Window covering positioning mechanism 100 of FIG. 4 is substantially similar to that of FIG. 1 and includes the same components. A portion of tube 102 is shown removed in FIG. 4 to illustrate features of rotational drive mechanism 104 and axial drive mechanism 106 positioned within tube 102. In addition, the rim portion of sleeve 302 connected to the end of tube 102 is illustrated in FIG. 4. In this embodiment, the window covering is in its lowest position therefore only a couple coils of cords 122a and 122b are shown around tube 102. Tube 102 is positioned adjacent rotational drive mechanism 104 when cords 122a and 122b are fully extended. In this position, stop ring 134a catches on bushing member 132a of bracket 130a so that cords 122a and 122b may not be unwound from tube 102 any further.

FIG. 5 is a front view of the window covering positioning mechanism of FIG. 4 with the window covering in a raised position (i.e. open position). In this embodiment, the window covering has been raised to an open position by advancing tube 102 in direction 502 away from rotational drive mechanism 104. The window covering is in its highest position and therefore cords 122a and 122b are almost fully coiled around tube 102. As previously discussed, tube 102 is advanced by pulling main cord 144 which in turn causes rotation and advancement of tube 102. During advancement, cords 122a and 122b are wound around tube 102 in a side by side arrangement as shown. Stop ring 134b eventually engages with bushing member 132b of bracket 130b to prevent any further raising of the window covering.

FIG. 6 is a back view of the window covering positioning mechanism of FIG. 5 with the window covering in the raised position. A detail view is provided to illustrate engagement of shoulder 602 of stop ring 134b and shoulder 604 of bushing member 132b. Shoulder 602 extends from an edge of stop ring 134b. Shoulder 604 extends from an edge of bushing member 132b. Once tube 102 is rotated and advanced to a desired limit, shoulder 602 catches on shoulder 604 and prevents any further rotation of tube 102. This in turn prevents the user from raising the window covering any farther.

When tube 102 is rotated in an opposite direction to lower the window covering, shoulders 602 and 604 of stop ring 132b and bushing member 134b, respectively, are dislodged from one another and tube 102 advances in an axial direction toward rotational drive mechanism 104. Eventually, if rotation and advancement of tube 102 continues in the same direction, stop ring 134a comes into contact with bushing member 132a of bracket 130a. The shoulders of stop ring 134a and bushing member 132a catch on one another to stop rotation and in turn advancement of tube 102. This prevents the window covering from being lowered any further.

In the embodiment illustrated in FIG. 6, aligning rail 140 is removed and bracket arms 608a, 608b and 606 extending from ends of brackets 130a, 130b and 138, respectively, are shown.

FIG. 7 is a perspective view of a back side of a window covering positioning mechanism with a window covering in a lowered position. Window covering positioning mechanism 100 is substantially the same as the window covering positioning mechanism discussed in reference to the previous figures and includes the same components. In this embodiment, window covering 702 is shown attached to window covering positioning mechanism 100. In some embodiments, window covering 702 is a folding shade made of a cloth material. A top edge of window covering 702 may be attached to aligning rail 140 using any suitable securing mechanism. Representatively, suitable securing mechanisms for securing the top edge of window covering 702 to aligning rail 140 may include screws, bolts or clips. Cords 122a and 122b are attached along an inner surface and at the end of window covering 702 to raise and lower window covering 702. In this embodiment, cords 122a and 122b are almost fully extended so that window covering 702 is in the closed position. Although a folding shade is described, it is further contemplated that window covering positioning mechanism 100 may be used with other types of window coverings such as flat folding shades, soft folding shades, balloon shades or natural woven shades.

FIG. 8 is a perspective view of a back side of a window covering positioning mechanism with a window covering in a raised position. Window covering positioning mechanism 100 is substantially the same as the window covering positioning mechanism discussed in reference to the previous figures and includes the same components. In this embodiment, cords 122a and 122b are shown almost fully coiled around tube 102 so that window covering 702 is in the open position.

FIG. 9 is a flow chart of a method 900 for assembling a window covering positioning mechanism. To assemble window covering positioning mechanism 100, rotational drive mechanism 104 is attached to an end of tube 102 (block 902). Housing 112 of rotational drive mechanism 104 is positioned within tube 102. Groove 114 of housing 112 and key 116 of tube 102 may be aligned to facilitate rotation of housing 102. Axial drive mechanism 106 is further positioned within tube 102 as previously discussed. Axial drive mechanism 106 is rotatably connected to an inner surface of tube 102 (block 904). In some embodiments, connector 118 and screw 106 are used to connect axial drive mechanism 106 and tube 102. In this aspect, connector 118 is positioned around axial drive mechanism 106 and screw 120 is screwed through an outer surface of tube 102 and into connector 118. Brackets 130a and 130b may be connected to tube 102 and bracket 138 may be connected to rotational drive mechanism 104 as previously discussed. Brackets 130a, 130b and 138 may then be positioned along aligning rail 140 as desired. Aligning rail 140 may then be mounted to a structure adjacent a window. Aligning rail 140 may be mounted directly to the structure, using, for example screws or bolts or by attaching aligning rail 140 to brackets mounted to the structure. It is further contemplated that aligning rail 140 could be replaced with a wooden board of equivalent size. Brackets and clutch mechanism may than screwed into the wooden board.

It is further contemplated that in embodiments where stop rings 134a and 134b are positioned around tube 102, brackets 130a, 130b and stop rings 134a, 134b may be positioned around tube 102 in the order of their arrangement. For example, wherein stop rings 134a and 134b are positioned between brackets 130a and 130b as shown in FIG. 1, bushing 132a of bracket 130a may be inserted over an end of tube 102 and positioned along tube 102 followed by stop ring 134a, stop ring 134b and then finally bushing 132b of bracket 130b. Cords 122a and 122b may then be attached to tube 102 using cord clips 124a and 124b.

It should be appreciated that reference throughout this specification to “one embodiment” or “an embodiment” means that a particular feature, structure or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Therefore, it is emphasized and should be appreciated that two or more references to “an embodiment” or “one embodiment” or “an alternative embodiment” in various portions of this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures or characteristics may be combined as suitable in one or more embodiments of the invention.

In the foregoing specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes can be made thereto without departing from the broader spirit and scope of the invention as set forth in the appended claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.

Claims

1. An apparatus comprising:

a tube to facilitate raising and lowering of a window covering;

a rotational drive mechanism coupled to the tube to drive rotation of the tube about an axis of the tube; and

an axial drive mechanism coupled to the tube to drive movement of the tube in an axial direction, the axial drive mechanism circumferentially disposed within the tube.

2. The apparatus of claim 1 wherein a connector assembly rotatably couples the tube to the axial drive mechanism.

3. The apparatus of claim 1 wherein the axial drive mechanism is dimensioned to advance the tube in the axial direction a distance equal to a diameter of a lifting cord coupled to the tube with each complete rotation of the tube.

4. The apparatus of claim 1 wherein the rotational drive mechanism comprises a rotatable housing coupled to an inner surface of the tube.

5. The apparatus of claim 4 wherein an outer surface of the housing comprises a groove dimensioned to receive a key extending from an inner surface of the tube.

6. The apparatus of claim 1 further comprising:

a stop ring coupled to the tube to limit rotation of the tube.

7. The apparatus of claim 1 further comprising:

a sleeve coupled to an end of the tube proximal to the rotational drive mechanism.

8. The apparatus of claim 1 further comprising:

a cord clip coupled to an outer surface of the tube.

9. A method comprising:

coupling a rotational drive mechanism to a tube for supporting a window covering; and

coupling an axial drive mechanism to an inner surface of the tube, the axial drive mechanism dimensioned to drive movement of the tube in an axial direction upon rotation of the tube by the rotational drive mechanism.

10. The method of claim 9 wherein the axial drive mechanism is coupled to the tube by rotatably positioning a cylindrical member around the axial drive mechanism and securing the cylindrical member to the tube.

11. The method of claim 10 wherein the axial drive mechanism and the cylindrical member comprise complimentary helical threading dimensioned to advance the tube in the axial direction a distance equal to a diameter of a window covering cord coupled to the tube with each complete rotation of the tube.

12. The method of claim 9 further comprising:

coupling a stop ring to the tube to limit rotation of the tube.

13. The method of claim 9 further comprising:

coupling a sleeve to an end of the tube proximal to the rotational drive mechanism.

14. The method of claim 9 further comprising:

coupling a cord clip to an outer surface of the tube to secure a cord from the window covering to the tube.

15. A kit comprising:

a tube around which a cord of a window covering is positioned;

a rotational drive mechanism to rotate the tube about an axis of the tube;

an axial drive mechanism to advance the tube in an axial direction; and

a connector to rotatably connect the tube to the axial drive mechanism.

16. The kit of claim 15 further comprising:

a bracket to support the tube.

17. The kit of claim 15 wherein the axial drive mechanism is dimensioned to advance the tube in the axial direction a distance equal to a diameter of the cord coupled to the tube with each complete rotation of the tube.

18. The kit of claim 15 further comprising:

a stop ring to limit rotation of the tube.

19. The kit of claim 15 further comprising:

a sleeve dimensioned to protect an end of the tube.

20. The kit of claim 15 further comprising:

a cord clip to secure the cord to an outer surface of the tube.