MOTORIZED WINDOW TREATMENT LIFT ASSISTANCE SYSTEMS AND METHODS

Abstract

A motorized window treatment system includes a motor drive unit physically coupled to a lift assistance subsystem. The lift assistance subsystem provides variable lift assistance to the motor drive unit for raising and lowering a covering material. The lift assistance subsystem includes a gradient spring that travels between a drive drum coupled to the motor drive unit and a storage drum disposed in a housing. A gradient spring travels between the drive drum and the storage drum to provide lift assistance and reduce the input power requirement for the motor drive unit. The housing includes a plurality of spring guide features disposed on an internal surface of the housing.

Description

DESCRIPTION OF THE RELATED ART

Summary

As described herein, a motor drive unit for a window treatment system may be configured to execute a test procedure for determining if the window treatment system is spring-balanced properly. The window treatment system may comprise first and second brackets for mounting the window treatment system to a structure and a covering material hang adjacent to the structure and to be adjusted between a fully-lowered position and a fully-raised position. The window treatment system may also comprise a lift assistance spring configured to provide variable lift assistance to the motor drive unit and a battery holder configured to receive at least one battery for powering the motor drive unit. During the test procedure, the motor drive unit may be configured to control the covering material between the fully-lowered position and the fully-raised position, and determine a magnitude of an input power of the motor drive unit as consumed from the battery during the movement of the covering material between fully-lowered position and the fully-raised position. When the magnitude of the input power exceeds a threshold during the movement of the covering material between the fully-lowered position and the fully-raised position, the motor drive unit may communicate an indication that the magnitude of the input power exceeded the threshold.

During the test procedure, the motor drive unit may be configured to control the covering material from the fully-lowered position to the fully-raised position, and also control the covering material from the fully-raised position to the fully-lowered position. When the magnitude of the input power exceeds the threshold during the movement of the covering material from fully-lowered position to the fully-raised position, the motor drive unit may communicate an indication that the window treatment system requires more lift assistance springs. When the magnitude of the input power exceeds a lower-movement threshold during the movement of the covering material from fully-raised position to the fully-lowered position, the motor drive unit may communicate an indication that the window treatment system requires less lift assistance springs.

The motor drive unit may be configured to execute the test procedure in response to receiving an input. For example, the motor drive unit may be configured to execute the test procedure in response to receiving a message. The motor drive unit may be configured to be paired with a remote control device and execute the test procedure in response to receiving the message from the remote control device via one or more wireless signals. The motor drive unit may also be configured to execute the test procedure in response to receiving the message using a short-range wireless communication protocol. In addition, the motor drive unit may be configured to execute the test procedure in response to an actuation of a button on the motor drive unit.

In addition, the motor drive unit may be configured to communicate a result of the test procedure. For example, the motor drive unit may be configured to communicate an indication that the window treatment system requires more lift assistance springs and/or an indication that the window treatment system requires less lift assistance springs. For example, the motor drive unit may be configured to communicate the indication that the result of the test procedure by blinking a visible indicator of the motor drive unit with a unique blink pattern. In addition, the motor drive unit may be configured to communicate the indication that the result of the test procedure by transmitting a message including the indication of the result of the test procedure.

As described herein, a motorized window treatment also includes a lift assistance subsystem to reduce the torque and consequently the power consumption of the drive system used to lift the window treatment to the retracted or raised position. The lift assistance spring can include a gradient spring that reversibly travels between a drive drum operatively and physically coupled to the drive shaft of the motor drive unit and a storage drum as the motor drive unit raises and lowers the window treatment. The drive drum and the storage drum may be disposed in a housing that includes one or more internal bumpers to guide the lift assistance spring as the spring reversibly travels between the drive drum and the storage drum. The motor drive unit shaft may be operatively coupled to the drive drum and extends at least partially through an aperture formed in the housing. Beneficially, the amount of lift assistance provided by the lift assistance subsystem can be tailored to specific application requirements. For example, where larger window treatments and/or heavier fabrics are desired, multiple lift assistance subsystems may be operatively coupled to the shaft of the motor drive unit.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a Roman shade system in a fully-lowered position.

FIG. 2 is a rear perspective view of the Roman shade system of FIG. 1 in the fully-lowered position.

FIG. 3 is a front perspective view of the Roman shade system of FIG. 1 in a fully-raised position.

FIG. 4 is a perspective view of an example of a head rail assembly of the Roman shade system of FIG. 1 where the Roman shade system comprises a single lift ring for each cord.

FIG. 5 is a perspective view of the head rail assembly of FIG. 4 where the Roman shade system comprises a pair of lift rings for each cord.

FIG. 6 is a perspective view of the head rail assembly of FIG. 4 where the Roman shade system comprises a pair of lift rings for attaching a ribbon to a roller tube of the head rail assembly.

FIG. 7 is a front view of the head rail assembly of FIG. 4.

FIG. 8A is an exploded view of the head rail assembly of FIG. 4 when a lift assistance subsystem of the head rail assembly comprises a single lift assistance spring.

FIG. 8B is a partial exploded view of the head rail assembly of FIG. 4 when a lift assistance subsystem of the head rail assembly comprises multiple lift assistance springs.

FIG. 9 is a perspective view of an example motor drive unit of the head rail assembly of FIG. 4.

FIG. 10 is a left-side perspective view of the head rail assembly of FIG. 4 with brackets removed.

FIG. 11 is a right-side perspective view of the head rail assembly of FIG. 4 with brackets removed.

FIG. 12 is a right-side view of a Roman shade system that includes the head rail assembly of FIGS. 4-11 when the Roman shade system is in a front-control configuration.

FIG. 13 is a right-side view of a Roman shade system that includes the head rail assembly of FIGS. 4-11 when the Roman shade system is in a rear-control configuration.

FIG. 14 is a partial exploded view of the head rail assembly of FIGS. 4-11 showing a bracket, a lift assistance subsystem, and a gear assembly of the head rail assembly in greater detail.

FIG. 15 is a flowchart of an example fabrication procedure for building a window treatment system, such as the Roman shade system of FIG. 1.

FIG. 16 is a block diagram of a motor drive unit of a motorized window treatment of a window treatment system.

FIG. 17 is a flowchart of an example test procedure for verifying proper spring-balancing of a window treatment system.

FIG. 18A is an exploded view of an illustrative lift assistance subsystem.

FIG. 18B is a cross-sectional view of the illustrative lift assistance subsystem depicted in FIG. 18A.

FIG. 19A is an exploded view of another illustrative lift assistance subsystem.

FIG. 19B is a cross-sectional view of the illustrative lift assistance subsystem depicted in FIG. 19A.

FIG. 19C is an elevation view of an enclosure portion used in conjunction with the illustrative lift assistance subsystem depicted in FIG. 19A.

FIG. 19D is another cross-sectional view of the illustrative lift assistance subsystem depicted in FIG. 19A.

DETAILED DESCRIPTION

FIG. 1 is a front perspective view and FIG. 2 is a rear perspective view of a window treatment system, such as a Roman shade system 100, in a fully-lowered position (e.g., a closed position and/or a fully-closed position). FIG. 3 is a front perspective view of the Roman shade system 100 in a fully-raised position (e.g., an open position and/or a fully-open position). The Roman shade system 100 may include a covering material, such as a shade fabric 102. The shade fabric 102 may come in different sizes, materials, and/or styles (e.g., such as a hobbled shade fabric as shown in FIG. 1-3). The variation in the size, material, and/or style of the shade fabric 102 of the Roman shade system 100 may lead to a variation in the weight of the shade fabric 102 from one installation to the next.

When the shade fabric 102 is a hobbled shade fabric as shown in FIGS. 1-3, the shade fabric 102 may be adapted to fold into a plurality of pleats 104 (e.g., horizontal pleats) as the Roman shade system 100 is opened. The pleats 104 may be formed by rigid battens 105 (e.g., dowels), which are sewn into the shade fabric 102 and extend horizontally across the width of the shade fabric. The Roman shade system 100 may comprise two or more ribbons 106 that extend along the length of a rear surface 108 of the shade fabric 102 and are attached to the rear surface 108 of the shade fabric 102 at the battens. Accordingly, the shade fabric 102 (e.g., the hobbled shade fabric) may hang with a plurality of folds 109 when the Roman shade system 100 is in the fully-lowered position as shown in FIGS. 1 and 2. The Roman shade system 100 may include one or more flexible members, such as cords 112 (e.g., three cords as shown in FIG. 2), which allow for raising and lowering of the shade fabric 102. The cords 112 may be attached to a lowest one 105a of the battens 105 and pass through a plurality of eyelets 114 (e.g., attachment points) that are coupled to the rear surface 108 of the shade fabric 102. The eyelets 114 may be coupled to the battens. Although three cords 112 are illustrated, it should be understood that fewer (e.g., one or two) or more cords may be used.

The Roman shade system 100 may comprise a head rail assembly 120, which may be located in an enclosure 119 (e.g., as shown in FIG. 2). FIG. 4 is a perspective view of the head rail assembly 120. The head rail assembly 120 may comprise a roller tube 122 that may be configured to rotate about a first axis 116 (FIG. 7), which may be a longitudinal axis of the roller tube 122. The roller tube 122 may extend from a first end 121 to a second end 123. As shown in FIGS. 1-3, the shade fabric 102 (e.g., a top end 102a of the shade fabric 102) may be attached (e.g., fixedly attached) to the enclosure 119 surrounding the head rail assembly 120 and may be configured to hang from the enclosure 119 (e.g., for covering an opening, such as a window). The cords 112 may be coupled to the roller tube 122 of the head rail assembly 120. The cords 112 may be configured to wrap around the roller tube 122 and a bottom end 102b of the shade fabric 102 may be configured to move as the roller tube 122 rotates. The enclosure 119 may hide the head rail assembly 120 from view. While the Roman shade system 100 is shown with the head rail assembly 120 located in the enclosure 119 in FIGS. 1-3, the head rail assembly 120 may also be installed without the enclosure 119 and the top end of the shade fabric 102 may be attached to a portion of the structure of the building around the head rail assembly 120.

The Roman shade system 100 may comprise one or more lift rings 110 (e.g., cord guides and/or collars), coupled to the roller tube 122 for guiding the cords 112 as the cords wind around and unwind from the roller tube 122. The lift rings 110 may each extend around the roller tube 122. For example, the Roman shade system 100 may comprise one lift ring 110 (e.g., a single lift ring) for each of the cords 112 of the Roman shade system 100. Each cord 112 may be attached to the respective lift ring 110 (e.g., such as at an inner side of the left lift ring 110 near the roller tube 122) and may extend from the lift ring 110 such that the cord 112 wraps around the roller tube 122 adjacent to one side of the respective lift ring 110 as the roller tube 122 rotates. While two lift rings 110 are shown in FIG. 4, the Roman shade system 100 may comprise more than two lift rings 110 around the roller tube 122 depending on the number of cords 112 required for the shade fabric 102 (e.g., one lift ring 110 for each cord 112).

In addition, the Roman shade system 100 may comprise a pair of lift rings 110 for each of the cords 112 in the Roman shade system 100, e.g., as shown in FIG. 5. The lift rings 110 of each pair of lift rings 110 may be spaced apart from each other along the roller tube 122. Each cord 112 may be attached to one of the lift rings 110 of each pair of lift rings 110, and may extend from the lift ring 110 such that the cords 112 may wrap around the roller tube 122 between the pair of lift rings 110 as the roller tube 122 rotates. While two pairs of lift rings 110 are shown in FIG. 5, the Roman shade system 100 may comprise more than two pairs of lift rings 110 around the roller tube 126 depending on the number of cords 112 required for the shade fabric 102 (e.g., one pair of lift rings 110 for each cord 112).

Further, rather than using the cords 112, the Roman shade system 100 may comprise one or more flexible members, such as ribbons 111 (e.g., straps) as shown in FIG. 6. For example, the ribbons 111 may have a narrow width (e.g., approximately ¼ inch or less). The ribbons 111 may each wrap around the roller tube 122 between adjacent lift rings 110 of each pair of lift rings 110. The Roman shade system 100 may comprise a pair of lift rings 110 for each of the ribbons 111 in the Roman shade system 100. Each ribbon 111 may be attached to a pin 113 (e.g., a rod) at one end of the ribbon 111. The pin 113 may be configured to be received in respective channels 115 in the lift rings 110 of each pair of lift rings 110. The lift rings 110 (of each pair of lift rings 110) may be spaced apart from each other along the roller tube 122, such that the pin 113 extends between the adjacent lift rings 110 and the ribbons 111 wrap around the roller tube 122 between the lift rings 110 as the roller tube 122 rotates. While two ribbons 111 and two pairs of lift rings 110 are shown in FIG. 6, the Roman shade system 100 may comprise more than two ribbons 111 and respective pairs of lift rings 110 around the roller tube 126 depending on the number of ribbons 111 required for the shade fabric 102 (e.g., one pair of lift rings 110 for each ribbon 111).

FIG. 7 is a front view is an exploded view of the head rail assembly 120. FIGS. 8 and 9 are exploded views of the head rail assembly 120. The roller tube 122 may be hollow such that the roller tube 122 defines an internal cavity 125 sized and configured to receive a motor drive unit 160 (e.g., a motor drive assembly) as shown in FIG. 7. For example, the position of the motor drive unit 160 in the roller tube 122 may be illustrated by a dashed line in FIG. 7. The motor drive unit 160 may be received in the first end 121 of the roller tube 122. One example of a motor drive unit is disclosed in U.S. Pat. No. 6,983,783, issued Jan. 10, 2006, entitled MOTORIZED SHADE CONTROL SYSTEM, the entire disclosure of which is hereby incorporated by reference.

FIG. 9 is a perspective view of the motor drive unit 160 removed from the roller tube 122. The motor drive unit 160 may include an internal motor (not shown) that may be coupled to a drive coupler 162 via a drive shaft 164 for rotatably driving the drive coupler 162. The drive coupler 162 may be notched about its outer periphery to facilitate engagement between the drive coupler 162 and an interior surface of the roller tube 122 in which the motor drive unit 160 is received. The motor drive unit 160 may further comprise an end portion 165 having a connector 166, such as a male or female connector, for connecting the motor drive unit 160 to a power source, such as one or more batteries 154 (e.g., as will be described in greater detail below). The end portion 165 may also have at least one button 167 for receiving user inputs and a visible indicator (not shown) that may be illuminated for providing feedback to a user of the Roman shade system 100. The motor drive unit 160 may comprise a bearing assembly 168, which may be rotatably coupled to the roller tube 122 at the first end 121 of the roller tube 122. The second end 123 of the roller tube 120 may receive an idler assembly 170 (FIG. 8A), which may be rotatably coupled to the roller tube 120 at the second end 123 of the roller tube 120. The motor drive unit 160 may be configured to transmit and/or receive messages (e.g., digital messages) via signals (e.g., wireless signals, such as radio-frequency signals), such that the motor drive unit 160 may be configured to rotate the roller tube 122 for raising and/or lowering the shade fabric 102 in response to received messages.

The head rail assembly 120 may also include a first bracket 130a and a second bracket 130b for mounting the Roman shade system 100 to a structure (e.g., a wall, a ceiling, a window frame, or other structure to which the Roman shade system is to be coupled). For example, the brackets 130a, 130b may each include a flange 132 defining holes 134. The holes 134 may be sized and configured to receive fasteners (e.g., screws) for coupling the brackets 130a, 130b to the structure. The first and second brackets 130a, 130b may be configured to support (e.g., rotatably support) the roller tube 122 (e.g., via a bearing assembly of the motor drive unit 160 and the idler assembly 170). The first bracket 130a may be coupled to the end portion 165 of the motor drive unit 160 and the second bracket 130b may be coupled to the idler assembly 170 to support (e.g., rotatably support) the roller tube 122. The first and second brackets 130a, 130b may comprise respective attachment structures for attaching to the end portion 165 of the motor drive unit 160 and the idler assembly 170, respectively. For example, the second bracket 130b may comprise an attachment structure 135 configured to attach to and support the idler assembly 170 (e.g., as shown in FIG. 8A). The first bracket 130a may comprise a corresponding attachment structure (not shown) configured to attach to and support the end portion 165 of the motor drive unit 160.

FIG. 10 is a left-side perspective view and FIG. 11 is a right-side perspective view of the head rail assembly 120 with the brackets 130a, 130b removed. The head rail assembly 120 may further include a housing 140 (e.g., an elongated housing or body), which extends from a first end 142 to a second end 144 (e.g., extends the length of the roller tube 122). The housing 140 may comprise sidewalls 146 that extend the length of the housing 140 from the first end 142 to the second end 144. The housing 140 may define an elongated slot 145 that may extend the length of the housing 140 from the first end 142 to the second end 144 (e.g., between the sidewalls 146 in a bottom of the housing 140). The first and second brackets 130a, 130b also may be configured to support (e.g., fixedly support) the housing 140. For example, the first and second brackets 130a, 130b may also include couplings, such as holes, recesses, detents, projections, and/or other physical constructions that facilitate coupling the first and second brackets 130a, 130b to the housing 140, either directly or indirectly. The first bracket 130a may be coupled to the first end 142 of the housing 140 and the second bracket 130b may be coupled to the second end 144 of the housing 140. The first and second brackets 130a, 130b may comprise walls 136 that line up with the sidewalls 146 of the housing 140. The housing 140 may be coupled to the first and second brackets 130a, 130b via fasteners 147 (e.g., screws) received in openings 138 in the first and second brackets 130a, 130b and openings 148 in the sidewalls 146 of the housing 140.

As shown in FIG. 8A, the head rail assembly 120 may further comprise a top cover 126 configured to cover a top of the head rail assembly 120 and a bottom cover 128 configured to cover a bottom of the head rail assembly 120. The top cover 126 may extend the length of the head rail assembly 120 (e.g., the length of the roller tube 122) between the first and second mounting brackets 130a, 130b. The bottom cover 128 may extend the length of the head rail assembly 120 (e.g., the length of the housing 140) and may cover the elongated slot 145 in the housing 140. The top cover 126 and the bottom cover 128 may be configured to attached to the head rail assembly 120 (e.g., to the first and second mounting brackets 130a, 130b) via one or more attachment mechanisms, such as snaps and/or fasteners (e.g., screws).

The housing 140 may house a battery holder 150 that may define a battery compartment 152 that may be sized and configured to receive the one or more batteries 154 for powering the motor drive unit 160. For example, the housing 140 may define an internal compartment 149 that is sized and configured to receive the battery holder 150. The battery holder 150 may comprise a cable 156 (e.g., electrical wiring) with a plug 155 at its end. The cable 156 may be electrically connected to the batteries 154 in the battery holder 150. The plug 155 may be configured to be electrically and mechanically connected to the connector 166 of the motor drive unit 160 for powering the motor drive unit 160. The cable 156 may extend from the battery holder 150 to the motor drive unit 160 adjacent to the first bracket 130a. The battery holder 150 may comprise a spring (not shown) for pushing the batteries 154 together and holding the batteries 154 in the battery compartment 152 of the battery holder 150 when the Roman shade system 100 is installed. The number and type of the batteries 154 that may be received in the battery compartment 152 of the battery holder 150 may be based on the type of window treatment system that will be supported. In some examples, the battery compartment 152 of the battery holder 150 may be sized and configured to receive five D-cell batteries, although one of ordinary skill in the art will understand that a different number and type (e.g., size and/or capacity) of batteries may be used depending on the power needs for a particular system. For example, while five D-cell batteries are referenced, one of ordinary skill in the art will understand that fewer (e.g., 1-4) or more batteries may be used. Additionally or alternatively, other types of batteries (e.g., A, AA, AAA, and/or lithium-ion batteries) may be used instead of D-cell batteries. In some examples, the motor drive unit 160 may be powered from an external power source, such as an alternating-current (AC) power source and/or a direct-current (DC) power supply, and/or from an energy-harvesting power source, such as a photovoltaic cell (e.g., a solar cell).

As shown in FIG. 8A, the battery holder 150 may be disposed at or adjacent to the first end 142 of the housing 140. Locating the motor drive unit 160 in the first end 121 of the roller tube 122 and the battery holder 150 adjacent to the first end 142 of the housing 140 may enable the plug 155 of the battery holder 150 to be electrically connected to the connector 166 of the motor drive unit 160 and may allow the cable 156 to be made as short as possible. In addition, the internal compartment 149 of the housing 140 in which the battery holder 150 is housed may be located below the roller tube 122, which may allow for easy access to the batteries 154 in the battery holder 150 when the Roller shade system 100 is installed to the structure. For example, the battery holder 150 may comprise a gap 158 (e.g., as shown in FIG. 11) through which the batteries 154 may be removed and replaced to allow for replacement of the batteries 154 through the elongated slot 145 in the housing 140. Since the batteries 154 may be received through the gap 158 in the battery holder 150 and the elongated slot 145 in the housing 140, the batteries 154 may be replaced without unmounting the head rail assembly 120 from the structure.

The head rail assembly 120 may also comprise a lift assistance subsystem 180, which may be housed and/or supported by the housing 140. For example, the internal compartment 149 of the housing 140 may also be sized and configured to receive and support the lift assistance subsystem 180, such that both the battery holder 150 and the lift assistance subsystem 180 may both be located in the internal compartment 149 of the housing 140. The lift assistance subsystem 180 may be configured to assist the motor drive unit 160 in the cavity 125 of the roller tube 122 with adjusting the shade fabric 102 between first and second positions (e.g., the fully-raised and fully-lowered positions or positions therebetween). In some examples, such as when the shade fabric 102 is a Roman shade fabric, the lift assistance subsystem 180 may include a lift assistance spring 182. The lift assistance spring 182 may comprise a spring member (not shown) contained within an enclosure 183. For example, the spring member of the lift assistance spring 182 may be a variable-force spring, such as a negative-gradient spring, which may have a negative-gradient force profile (e.g., decreasing load with increasing deflection). The negative-gradient spring of the lift assistance spring 182 may provide greater assistance (e.g., a greater force) when the shade fabric 102 is near the fully-raised position as compared to when the shade fabric 102 is near the fully-lowered position (e.g., as there is less torque required to move the roller tube 122 when the shade fabric 102 is near the fully-lowered position compared to when the shade fabric 102 is near the fully-raised position). For example, the lift assistance subsystem 180 may comprise a single lift assistance spring 182 as shown in FIG. 8A or multiple lift assistance springs 182 as shown in FIG. 8B.

The lift assistance subsystem 180 may comprise a shaft 184 that may be configured to rotate about a second axis 118 (FIG. 7). The shaft 184 may extend through a channel 185 (e.g., a keyed channel) in the enclosure 183 of the lift assistance spring 182. The channel 185 may extend all the way through the enclosure 183 of the lift assistance spring 182. The channel 185 may be keyed to engage with the shaft 184 (e.g., the channel 185 may have a cross-sectional area that substantially matches a cross-sectional area of the shaft 184). As the shaft 184 rotates about the second axis 118 in first and second angular directions, the spring member in the enclosure 183 of the lift assistance spring 182 may tighten and loosen, respectively. The channel 185 may be rotatable such that rotations of the shaft 184 (e.g., when received in the channel 185) may cause the channel 185 to rotate, which may cause the spring member of the lift assistance spring 182 to expand and contract. For example, the shaft 184 may have a varying length depending on the number of the lift assistance springs 182 in the lift assistance subsystem 180 (e.g., as shown in FIG. 8B where the shaft 184 is broken). In some examples, the lift assistance spring 182 may comprise as integral shaft that extends from the enclosure 183 and the shafts of adjacent lift assistance springs may be coupled together

The head rail assembly 120 may comprise a clamp 181 that may be received in the internal cavity 149 of the housing 140 (e.g., spanning the elongated slot 145 as shown in FIG. 10). The clamp 181 may tightened to be held in place in the internal cavity 149 of the housing 140 in a location at which the clamp 181 abuts against the lift assistance spring 182 of the lift assistance subsystem 180 (e.g., to hold the lift assistance spring 182 against the second bracket 130b). The location of the clamp 181 is adjustable depending on the number of lift assistance spring 182 in the lift assistance subsystem 180.

The roller tube 122 may be coupled to the shaft 184 of the lift assistance subsystem 180 via a gear assembly 190. FIGS. 12-13 are right side views of the Roman shade system 100 (e.g., with the right-side bracket 130b of the head rail assembly 120 not shown in order to illustrate the gear assembly 190 in greater detail). FIG. 12 shows the Roman shade system 100 in a front-control configuration (e.g., a rear-fabric configuration) and FIG. 13 shows the Roman shade system 100 in a rear-control configuration (e.g., a front-fabric configuration). FIG. 14 is a partial exploded view of the head rail assembly 120 showing the second bracket 130b, the light assistance subsystem 180, and the gear assembly 190 in greater detail. The gear assembly 190 may be supported by the second bracket 130b and may be configured to mechanically couple the roller tube 122 to the lift assistance spring 182 of the lift assistance subsystem 180 (e.g., as will be described in greater detail below).

In the front-control configuration shown in FIG. 12, the head rail assembly 120 may be located towards the room in which the Roman shade system 100 is installed and the shade fabric 102 may be located towards the window that the Roman shade system 100 is adapted to cover (e.g., the window may be located to the right of the shade fabric 102 as shown in FIG. 12). The cords 112 may extend from the roller tube 122 through an opening 115 in the shade fabric 102 towards the lowest one of the battens 105 between the shade fabric 102 and the window. In the front-control configuration, the shade fabric 102 may hang from the window-side of the enclosure 119 and may wrap around the enclosure 119 as shown in FIG. 12 to provide an aesthetically pleasing appearance for the enclosure 119.

In the rear-control configuration shown in FIG. 13, the head rail assembly 120 may be located towards the window that the Roman shade system 100 is adapted to cover and the shade fabric 102 may be located towards the room in which the Roman shade system 100 is installed (e.g., the window may be located to the right of the shade fabric 102 as shown in FIG. 13). The cords 112 may extend from the roller tube 122 towards the lowest one of the battens 105 between the shade fabric 102 and the window. In the rear-control configuration, the shade fabric 102 may hang from the room-side of the enclosure 119 and may wrap at least partially around the enclosure 119 as shown in FIG. 13 to provide an aesthetically pleasing appearance for the enclosure 119.

The gear assembly 190 may comprise a first gear 192 that may be coupled (e.g., fixedly coupled) to the roller tube 210 (e.g., to the second end 214 of the roller tube 122) and may be configured to rotate about the first axis 116. For example, the idler assembly 170 may comprise a stationary portion 172 (FIGS. 12 and 13) configured to be attached to (e.g., fixedly attached to) the attachment structure 135 (FIG. 14) of the second bracket 130b. The idler assembly 170 may also comprise a rotatable portion 174 configured to be received in the second end 123 of the roller tube 122 and attached to (e.g., fixedly attached to) the roller tube 122. For example, the rotatable portion 174 may comprise notches 176 configured to receive ribs (not shown) on an inner surface of the roller tube for fixedly attaching the rotatable portion 174 to the roller tube 122. The rotatable portion 174 may be configured to rotate around the stationary portion 172, e.g., as the motor drive unit 160 rotates the roller tube 122. For example, the stationary portion 172 and the rotatable portion 174 may meet at a bearing surface (not shown). The first gear 192 may be connected to (e.g., formed as a part of) the rotatable portion 174 of the idler assembly 170, such that the first gear 192 rotates as the roller tube 122 rotates.

The gear assembly 190 may also comprise a second gear 194 that may be coupled (e.g., fixedly coupled) to the shaft 184 of the lift assistance subsystem 180 and may be configured to rotate about the second axis 118. The second gear 194 may comprise an opening 198 configured to receive and attach to the shaft 184 of the lift assistance subsystem 180. The second gear 194 may also comprise a drum 199 (e.g., a cylindrical drum) configured to be received (e.g., rotatably received) within an opening 139 (e.g., a cylindrical opening) in the second bracket 130b. The gear assembly 190 may comprise a third gear 196 located between the first and second gears 192, 194, and configured to mechanically couple the first gear 192 to the second gear 194. The second bracket 130b may support the first, second, and third gears 192, 194, 196 of the gear assembly 190. The engagement between the first, second, and third gears 192, 194, 196 of the gear assembly 190 may provide the connection through which the lift assistance subsystem 180 provides the assistance to the motor of the motor drive unit 160 in moving the shade fabric 102.

In operation, the motor of the motor drive unit 160 may cause the roller tube 122 to rotate in either a first angular direction (e.g., clockwise) or a second angular direction (e.g., counterclockwise) depending on whether the shade fabric 102 is to be moved toward the fully-lowered position or toward the fully-raised position. As the roller tube 122 rotates, the cords 112, for example, may be either wound around the roller tube 122 (e.g., guided by the lift rings 110) or unwound from the roller tube 122 depending on the direction of the rotation. When the cords 112 are wound around the roller tube 122, the cords 112 may pull on the battens 105 to cause the shade fabric 102 to raise and fold. For example, if starting in the fully-lowered position, rotation of the roller tube 122 may cause the cords 112 to wind around the roller tube 122, which may result in the lowest one of the battens 105 (e.g., along with the shade fabric 102) being pulled in an upward direction. When the lowest one of the battens 105 contacts the next highest batten, both the lowest one of the battens 105 and the next highest one of the battens 105 may move together in an upward direction. When lowering of the shade fabric 102, all of the battens 105 may move together until a pleat is fully expanded at which point the upper-most batten may stop moving (e.g., due to its engagement with the shade fabric 102) and the remainder of the lower battens 105 may continue to move in a downward direction until all of the battens 105 reach their lowest position.

Since the shade fabric 122 may vary in size, material, and/or style from one installation of the Roller shade system 100 to the next (e.g., and thus vary in weight from one installation to the next), the lift assistance subsystem 180 may be re-configurable such that the motor drive unit 160 may be assembled to raise and lower shade fabrics of a particular weight. For example, the lift assistance subsystem 180 of the head rail assembly 120 may be configured to include multiple lift assistance springs (e.g., each of which may be the same as the lift assistance spring 182) as shown in FIG. 8B. The number of lift assistance springs installed in the head rail assembly 120 may depend on the weight of the shade fabric 102. For example, when the lift assistance subsystem 180 includes multiple lift assistance springs 182, the shaft 184 of the lift assistance subsystem 180 may extend through respective openings 185 in multiple lift assistance springs 182 and thus engage with the multiple lift assistance springs 182 as the shaft 184 rotates (e.g., to provide additional assistance to the motor drive unit 160). The internal cavity 149 of the housing 140 may be sized and configured to received and support multiple lift assistance springs 182.

When the lift assistance subsystem 180 includes multiple lift assistance springs 182, the lift assistance springs 182 may be lined up together along the shaft 184, such that the lift assistance springs 182 make contact with each other. As shown in FIG. 14, the enclosure 183 of each lift assistance spring 182 may comprise a group (e.g., a pair) of alignment members, e.g., a protrusion 186 and a recess 187, on each side of the enclosure 183 of the lift assistance spring 182. While only one group (e.g., pair) of alignment members can be seen in FIG. 14, the lift assistance spring 182 may comprise a second pair of alignment members on the opposite side of the enclosure 183. In addition, each group of alignment members may have more or less than a pair (e.g., more or less than two) alignment members. When two of the lift assistance springs 182 are lined up together along the shaft 184, the protrusion 186 on a first one of the lift assistance springs 182 may be received in the recess 187 on a second one of the lift assistance springs 182, and the protrusion 186 on the second one of the lift assistance springs 182 may be received in the recess 187 on the first one of the lift assistance springs 182. In addition, the enclosure 183 of each one of the lift assistance springs 182 may comprise a snap 188 configured to couple to a ledge 189 on an adjacent one of the lift assistance springs 182. In this way, the lift assistance springs 182 are securely connected and aligned and can be inserted as a unit.

When there are too many or two few of the lift assistance springs 182 in the lift assistance subsystem 180, the Roller shade system 100 may not be spring-balanced correctly. When the Roller shade system 100 is not spring-balanced correctly, the load on the motor drive unit 160 may be increased when raising or lowering the shade fabric 102. This may increase a magnitude of a battery current drawn from the batteries 154 and thus power consumed by the motor drive unit 160 (e.g., power consumed from the batteries 154), which may lead to a shorter lifetime of the batteries 154. After the shade fabric 102 is installed on the head rail assembly 120, the motor drive unit 160 may be configured to execute a test procedure (e.g., a spring-balance verification procedure) to confirm that a proper number of the lift assistance spring 182 (e.g., a number of lift assistance springs 182 that achieves an optimal amount of power consumed from the batteries 154) are installed and/or to determine if the lift assistance subsystem 180 needs more or less lift assistance springs 182.

FIG. 15 is a flowchart of an example fabrication procedure 200 for building and/or configuring a window treatment system (e.g., such as the Roman shade system 100 shown in FIGS. 1-3). The fabrication procedure 200 may be performed by a technician (e.g., a manufacturing technician). The fabrication procedure 200 may be performed at a manufacturing facility, at the installation site of the window treatment system, and/or at another location. The fabrication procedure 200 may start at 210. At 212, a technician, for example, may install a covering material (e.g., the shade fabric 102) to a head rail assembly (e.g., the head rail assembly 120) of the window treatment system. For example, the covering material may be of a fabric type and size as specified by a customer. In addition, the technician may install one or more cords (e.g., the cords 112) and/or ribbons (e.g., ribbons 111) onto a roller tube of the head rail assembly (e.g., the roller tube 122) at 212.

At 214, the technician may determine a number (e.g., an initial number) of lift assistance springs (e.g., the lift assistance springs 182) to install in the head rail assembly. For example, the technician may determine the initial number of lift assistance springs based on the size, material, style, and/or weight of the covering material. The technician may refer to a reference guide (e.g., a table) that may identify the initial number of lift assistance springs based on the size, material, style, and/or weight of the covering material. In addition, the technician may use a program running on a computing device (e.g., computer, laptop, tablet, smart phone, etc.), which may identify the initial number of lift assistance springs after the size, material, style, and/or weight of the covering material are entered into the program. At 216, the technician may install the initial number of lift assistance springs in the head rail assembly. For example, the technician may connect enclosures of the lift assistance springs together and insert the lift assistance springs in an internal cavity of a housing of the head rail assembly (e.g., the internal cavity 149 of the housing 140), such that a shaft (e.g., the shaft 184) is received through channels of the lift assistance springs. In addition, the technician may install a bracket (e.g., the second bracket 130b) on an end of the housing and position a clamp 181 within the internal cavity of the housing to hold the lift assistance springs against the bracket at 216. At 218, the technician may install one or more batteries (e.g., the batteries 154) in a battery holder (e.g., the battery holder 150), insert the battery holder in the internal cavity of the housing, and install a bracket (e.g., the first bracket 130a) on another end of the housing.

At 220, the technician may mount the head rail assembly to a test installation structure, which may allow a motor drive unit (e.g., the motor drive unit 160) of the window treatment system to fully raise and fully lower the covering material. At 222, the technician may cause the motor drive unit of the window treatment system to execute a test procedure (e.g., a spring-balancing verification procedure). For example, the technician may actuate a button on the motor drive unit to cause the motor drive unit to execute the test procedure. In addition, the motor drive unit may be configured to execute the text procedure in response to receiving a message from an external device. For example, the technician may associate (e.g., pair) a remote control device (e.g., a wireless remote control device) with the motor drive unit and actuate a button on the remote control device to cause the remote control device to transmit a message to the motor drive unit (e.g., via one or more wireless signals) for causing the motor drive unit to execute the test procedure. Additionally or alternatively, the technician may use a computing device (e.g., a smart phone or tablet) to transmit a message to the motor drive unit via a wired or wireless communication link. For example, the computing device may be configured to transmit the message to the motor drive unit using a standard wireless communication protocol (e.g., such as the WI-FI protocol and/or the BLUETOOTH protocol) for causing the motor drive unit to execute the test procedure.

Once the test procedure has been started, the motor drive unit may be configured to rotate the roller tube to cause the window treatment system to move the covering material while monitoring an input power of the motor drive unit. For example, the motor drive unit may be configured to move the covering material through a full-raise movement (e.g., from a fully-lowered position to a fully-raised position) and a full-lower movement (e.g., from the fully-raised position to the fully-lowered position). The motor drive unit may be configured to monitor (e.g., periodically monitor) a magnitude of an input power P_IN of the motor drive unit (e.g., a power consumed from the batteries) while the motor drive unit is moving the covering material through the full-raise movement and the full-lower movement.

The motor drive unit may be configured to determine a result of the test procedure by comparing the magnitude of the input power P_IN to one or more power thresholds while the motor drive unit is moving the covering material during the test procedure. The motor drive unit may be configured to determine that the window treatment system requires at least one more lift assistance spring when the input power P_IN of the motor drive unit exceeds a raise-movement power threshold P_TH-RAISE when the motor drive unit is raising the covering material during the full-raise movement. The motor drive unit may be configured to determine that the window treatment system requires at least one less lift assistance spring when the input power P_IN of the motor drive unit exceeds a lower-movement power threshold P_TH-LOWER when the motor drive unit is lowering the covering material during the full-lower movement. The motor drive unit may be configured to determine that the window treatment system is appropriately spring-balanced when the magnitude of the input power P_IN of the motor drive unit does not exceed the raise-movement power threshold P_TH-RAISE when the motor drive unit is raising the covering material during the full-raise movement and the input power P_IN of the motor drive unit does not exceed the lower-movement power threshold P_TH-LOWER when the motor drive unit is lowering the covering material during the full-lower movement. For example, the raise-movement power threshold P_TH-RAISE may be equal to the lower-movement power threshold P_TH-LOWER. In some examples, the raise-movement power threshold P_TH-RAISE may be different than the lower-movement power threshold P_TH-LOWER.

The motor drive unit may be configured to communicate an indication of the result of the test procedure (e.g., an indication that the window treatment system is appropriately spring-balanced, an indication that the window treatment system requires more lift assistance springs, or an indication that the window treatment system requires less lift assistance springs). For example, the indication of the result of the test procedure may be an indication that the magnitude of the input power P_IN exceeded one of the raise-movement power threshold P_TH-RAISE or the lower-movement power threshold P_TH-LOWER while the motor drive unit was moving the covering material during the test procedure. The motor drive unit may be configured to communicate the indication of the result of the test procedure by illuminating a visible indicator (e.g., the visible indicator on the end portion 165 of the motor drive unit 160, such as a light-emitting diode) to provide the indication of the result of the test procedure. For example, the motor drive unit may be configured to blink the visible indicator with a unique blink sequence (e.g., pattern) to indicate each of the different results of the test procedure (e.g., the window treatment system is appropriately spring-balanced, requires more lift assistance springs, or requires less lift assistance springs). The technician may view and interpret the unique blink sequence for determining the result of the test procedure. The motor drive unit may be configured to blink visible indicator with the unique blink sequence to indicate the result of the test procedure at the end of the test procedure (e.g., after the full-raise movement and/or the full-lower movement). For example, the motor drive unit may be configured to blink the visible indicator with the unique blink sequence multiple times to ensure that the technician can view and interpret the unique blink sequence. In some examples, the motor drive unit may be configured to blink the visible indicator with the unique blink sequence when the magnitude of the input power P_IN of the motor drive unit exceeds the raise-movement power threshold P_TH-RAISE during and/or after the full-raise movement and when the magnitude of the input power P_IN of the motor drive unit exceeds the lower-movement power threshold P_TH-LOWER during and/or after the full-lower movement. While the motor drive unit is described as having a single visible indicator, the motor drive unit may alternatively comprise more than one visible indicator and/or a more complex visible indicator, such as a visible display.

Additionally or alternatively, the motor drive unit may be configured to communicate the indication of the result of the test procedure by transmitting a message via signals (e.g., wireless signals, such as radio-frequency signals). For example, the motor drive unit may be configured to transmit a message including the indication of the result of the test procedure to a computing device used by the technician (e.g., a personal computer, laptop, tablet, smart phone, etc.). The computing device may be configured to display the indication of the result of the test procedure on a visible display of the computing device. For example, the motor drive unit may be configured to transmit the message including the indication of the result of the test procedure to the computing device at the end of the test procedure (e.g., after the full-raise movement and/or the full-lower movement).

After the motor drive unit communicates the indication of the result of the test procedure (e.g., the test procedure is complete), the technician may respond to the result of the test procedure. When the result of the test procedure is that the window treatment system needs more lift assistance springs at 224, the technician may add one lift assistance spring to the head rail assembly of the window treatment system at 226 and then may test the operation of the window treatment system again at 222. When the result of the test procedure is that the window treatment system does not need more lift assistance spring at 224, but needs less lift assistance springs at 228, the technician may remove one lift assistance spring from the head rail assembly of the window treatment system at 230 and then may test the operation of the window treatment system again at 222. When the result of the test procedure is that the window treatment system does not need more lift assistance springs at 224 and does not need less lift assistance springs at 228 (e.g., the window treatment system is appropriately spring-balanced), the fabrication procedure 200 may end at 232.

While the fabrication procedure 200 has been described with the motor drive unit providing a unique blink sequence (e.g., pattern) to indicate each of the different results of the test procedure (e.g., the window treatment system is appropriately spring-balanced, requires more lift assistance springs, or requires less lift assistance springs), in some examples the motor drive unit may not be configured to provide a unique blink sequence (e.g., have no response) when the window treatment system is appropriately spring-balanced, but may only provide a unique blink sequence when the window treatment system requires more lift assistance springs or requires less lift assistance springs. In addition, in some examples, the motor drive unit may be configured to provide a single blink sequence when the window treatment system is not appropriately spring-balanced (e.g., the motor drive unit may not provide a unique blink sequence when the window treatment system requires more lift assistance springs as compared to when the window treatment system requires less lift assistance springs). In such an example, the technician may determine if the single blink sequence is provided when the motor drive unit is moving through the full-raise movement or the full-lower movement to determine when the window treatment system requires more lift assistance springs or when the window treatment system requires less lift assistance springs, respectively.

In addition, while the fabrication procedure 200 has been described with the motor drive unit moving through the full-raise movement and the full-lower movement during the test procedure at 222, the fabrication procedure 200 may also be implemented with the motor drive unit only moving the covering material through one of the movements, for example, the full-raise movement. For example, the technician may not need to determine the initial number of lift assistance springs to install in the head rail assembly at 214 (e.g., 214 may be omitted from the fabrication procedure 200), but may simply install a single lift assistance spring in the head rail assembly at 216. The motor drive unit may execute the test procedure and only move the covering material through the full-raise movement during the test procedure at 222. The motor drive unit may be configured to communicate an indication that the window treatment system requires more lift assistance springs during and/or after the full-raise movement. The technician may repeatedly execute the test procedure until the correct number of lift assistance springs are added to and/or installed in the head rail assembly. Further, the fabrication procedure 200 may be implemented with the technician initially installing the maximum number of lift assistance spring in the head rail assembly and only moving the covering material through the full-lower movement during the test procedure to determine whether less lift assistance springs are required.

While the fabrication procedure 200 has been described herein with the technician determining whether to install more or less lift assistance springs of the same type in the window treatment system, the fabrication procedure 200 may also be used to determine whether to install lift assistance springs of different forces and/or force gradients (e.g., lift assistance springs providing more or less force) to replace an existing lift assistance spring. For example, the technician may install a lift assistance spring that provides more force at 226 and/or a lift assistance spring that provides less force at 230. In addition, the fabrication procedure 200 may be used to determine whether to install lift assistance spring of different forces and/or force gradients on in a single window treatment system.

FIG. 16 is a block diagram of a motor drive unit 300 (e.g., the motor drive unit 160) of a window treatment system (e.g., the Roman shade system 100). The motor drive unit 300 may include a motor 310 (e.g., a direct-current motor) that may be coupled to a roller tube of the motorized window treatment (e.g., the roller tube 122) for rotating the roller tube. Rotation of the roller tube may be configured to raise and lower a covering material (e.g., the shade fabric 102). The motor drive unit 300 may comprise a compartment 332 (e.g., which may be an example of the battery holder 150 of the head rail assembly 120 shown in FIGS. 4-8) that is configured to receive a DC power source. The DC power source may be, for example, one or more batteries 330. In this example, the compartment 332 may be configured to receive one or more batteries 330 (e.g., four “D” batteries), such as the batteries 154 of FIGS. 4-8. The batteries 330 may provide a battery voltage V_BATT to the motor drive unit 300. In addition, alternate DC power sources, such as a solar cell (e.g., a photovoltaic cell), an ultrasonic energy source, and/or a radio-frequency (RF) energy source, may be coupled in parallel with the one or more batteries 330, or in some examples be used as an alternative to the batteries 330. Further, an external DC power supply may be configured to be coupled in parallel with the one or more batteries 330. The alternate DC power source and/or the external DC power supply may be used to perform the same and/or similar functions as the one or more batteries 330.

The motor drive unit 300 may include a motor drive circuit 312 (e.g., an H-bridge drive circuit) that receives the battery voltage V_BATT and may generate a pulse-width modulated (PWM) voltage V_PWM for driving the motor 310. While not shown in FIG. 16, the motor drive unit 300 may comprise a power converter circuit (e.g., a boost converter circuit) coupled between the batteries 330 and the motor drive circuit 312 for receiving the battery voltage V_BATT and generating a boosted voltage that may be received by the motor drive circuit 312 for driving the motor 312. The motor drive unit 300 may also include a power supply 314 that may receive the battery voltage V_BATT and generate a supply voltage V_CC for powering the low-voltage circuitry of the motor drive unit 300.

The motor drive unit 300 may include a control circuit 320 for controlling the operation of the motor 210. The control circuit 320 may include, for example, a microprocessor, a programmable logic device (PLD), a microcontroller, an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or any suitable processing device or control circuit. The control circuit 320 may be configured to generate one or more drive signals V_DR for controlling the motor drive circuit 312. The one or more drive signals V_DR may be configured to control a rotational speed and/or a direction of rotation of the motor 310. For example, as shown in FIG. 16, the motor drive circuit 312 and the control circuit 320 may conduct a battery current I_BATT from the batteries 330. The control circuit 320 may be configured to control the motor drive circuit 312 to rotate the motor 310 to adjust a present position P_PRES of the covering material between a fully-raised position P_RAISED and a fully-lowered position P_LOWERED.

The motor drive unit 300 may include a rotational position sensing circuit 322, such as, for example, a Hall effect sensor (HES) circuit, which may be configured to generate first and second rotational position sensing signals V_S1, V_S2. The first and second rotational position sensing signals V_S1, V_S2 may indicate the rotational speed and/or the direction of the motor 310 to the control circuit 320. The rotational position sensing circuit 322 may include other suitable position sensors, such as, for example, magnetic, optical, and/or resistive sensors. The control circuit 320 may be configured to determine the rotational position of the motor 310 in response to the first and second rotational position sensing signals V_S1, V_S2 generated by the rotational position sensing circuit 322. The control circuit 320 may be configured to determine a present position of the covering material in response to the rotational position of the motor 310. The operation of a motor drive circuit and a rotational position sensing circuit of an example motor drive unit is described in greater detail in commonly-assigned U.S. Pat. No. 5,848,634, issued Dec. 15, 1998, entitled MOTORIZED WINDOW SHADE SYSTEM, and commonly-assigned U.S. Pat. No. 7,839,109, issued Nov. 23, 2010, entitled METHOD OF CONTROLLING A MOTORIZED WINDOW TREATMENT, the entire disclosures of which are hereby incorporated by reference.

The motor drive unit 300 may comprise a memory 324 configured to store operational characteristics, e.g., such as the present position of the covering material and/or limits for controlling the position of the covering material (e.g., the fully-raised position P_RAISED and/or the fully-lowered position P_LOWERED). The memory 324 may be implemented as an external integrated circuit (IC) or as an internal circuit of the control circuit 320. The memory 324 may comprise a computer-readable storage media or machine-readable storage media that maintains computer-executable instructions for performing one or more procedure and/or functions as described herein. For example, the memory 324 may comprise computer-executable instructions or machine-readable instructions that when executed by the control circuit configure the control circuit to provide one or more portions of the procedures described herein (e.g., such as a test procedure 400 shown in FIG. 17). The control circuit 320 may access the instructions from memory 324 for being executed to cause the control circuit 320 to operate as described herein, or to operate one or more other devices as described herein. The memory 324 may comprise computer-executable instructions for executing configuration software. For example, the operational characteristics and/or the association information stored in the memory 324 may be configured during a configuration procedure of the sensor device 300.

The motor drive unit 300 may include a communication circuit 325 that may allow the control circuit 320 to transmit and receive signals, e.g., wired signals and/or wireless signals, such as radio-frequency (RF) signals. The control circuit 320 may be configured to control the motor 310 to control the movement of the covering material in response to a shade movement command received in signals received via the communication circuit 325 from a remote control device. During a configuration procedure (e.g., an association procedure), the motor drive unit 300 may be associated with the remote control device, such that the motor drive unit 300 may be responsive to the messages transmitted by the remote control device (e.g., via wireless signals).

The motor drive unit 300 may comprise an actuator circuit 326 configured to receive user inputs. The actuator circuit 326 may comprise one or more switching devices, such as mechanical tactile switches that are configured to be actuated in response to actuations of one or more respective buttons on the motor drive unit 300 (e.g., the button on the end portion 165 of the motor drive unit 160). The control circuit 320 may be responsive to actuations of the switching devices of the actuator circuit 326. For example, the control circuit 320 may be configured to enter the configuration procedure (e.g., for being associated with the remote control device) in response to an actuation of one of the buttons of the motor drive unit 300.

The motor drive unit 300 may include a light source 328 that may be illuminated by the control circuit 320 to provide feedback to the user of the motorized window treatment. For example, the control circuit 320 may be configured to illuminate the light source 328 to provide feedback to the user during the configuration mode to indicate that the motor drive unit is in the configuration mode. For example, the light source 228 may comprise one or more light-emitting diodes (LEDs).

The motor drive unit 300 may comprise a battery-voltage sense circuit 334 that may be electrically coupled in parallel with the batteries 330 for receiving the battery voltage V_BATT and generating a battery-voltage sense signal V_V-BATT that may indicate the magnitude of the battery voltage V_BATT. For example, the battery-voltage sense circuit 334 may comprise a resistive divider circuit having two resistors coupled in series, with the series combination of the resistor coupled in parallel with the batteries 330. The battery-voltage sense signal V_V-BATT may be generated at the junction of the resistors, such that a magnitude of the battery-voltage sense signal V_V-BATT is proportional to the magnitude of the battery voltage V_BATT.

The motor drive unit 300 may comprise a battery-current sense circuit 336 that may be electrically coupled in series with the batteries 330 for conducting the battery current I_BATT and generating a battery-current sense signal V_I-BATT that may indicate the magnitude of the battery current I_BATT. For example, the battery-current sense circuit 336 may comprise a sense resistor circuit coupled in series with the batteries 330 (e.g., for conducting the battery current I_BATT). The battery-current sense signal V_I-BATT may be generated at across the sense resistor, such that a magnitude of the battery-current sense signal V_I-BATT is proportional to the magnitude of the battery current I_BATT.

The control circuit 320 may receive the battery-voltage sense signal V_V-BATT from the battery-voltage sense circuit 334 and the battery-current sense signal V_I-BATT from the battery-current sense circuit 336. For example, the control circuit 320 may comprise one or more analog-to-digital converters (ADCs) for sampling the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT. The control circuit 320 may be configured to monitor a magnitude of an input power P_IN of the motor drive unit 300 (e.g., a power consumed from the batteries 330). The control circuit 320 may be configured to determine the magnitude of the input power P_IN of the motor drive unit 300 based on the magnitude of the battery-voltage sense signal V_V-BATT and the magnitude of the battery-current sense signal V_I-BATT. For example, the control circuit 320 may be configured to calculate the magnitude of the input power P_IN by multiplying the magnitude of the battery voltage V_BATT (e.g., as indicated by the magnitude of the battery-voltage sense signal V_V-BATT) by the magnitude of the battery current I_BATT (e.g., as indicated by the magnitude of the battery-current sense signal V_I-BATT). In some examples, the control circuit may determine the magnitude of the input power P_IN of the motor drive unit 300 (e.g., a power consumed from the batteries) based on (e.g., based on only) the battery-current sense signal V_I-BATT (e.g., the motor drive unit 300 may not comprise the battery-voltage sense circuit 334). For example, the control circuit may assume that the magnitude of the battery voltage V_BATT is a predetermined constant value, and calculate the magnitude of the input power P_IN by multiplying the predetermined constant value of the battery voltage V_BATT by the magnitude of the battery current I_BATT (e.g., as indicated by the magnitude of the battery-current sense signal V_I-BATT).

The lifetime of the batteries 330 may be dependent on the input power P_IN of the motor drive unit 300 (e.g., the power consumed from the batteries 330) during each movement of the covering material. The control circuit 320 may be configured to monitor the magnitude of the input power P_IN while controlling the motor drive circuit 312 to rotate the motor 310 to adjust the present position P_PRES of the covering material between the fully-raised position P_RAISED and the fully-lowered position P_LOWERED. The control circuit 320 may be configured to determine that the magnitude of the input power P_IN of the motor drive unit 300 (e.g., the power consumed from the batteries 330) is too large when the magnitude of the input power P_IN exceeds one or more power thresholds. The magnitude of the input power P_IN of the motor drive unit 300 may be too large when the window treatment system is not spring-balanced appropriately.

The control circuit 320 may be configured to execute a test procedure (e.g., the test procedure executed at 222 of the fabrication procedure 200) to determine if the window treatment system is spring-balanced correctly. The control circuit 320 may be configured to execute the test procedure in response to an actuation of one of the buttons of the motor drive unit 300 detected by the actuator circuit 326. In addition, the control circuit 320 may be configured to execute the test procedure in response to receiving a message via the communication circuit 325. During the test procedure, the control circuit 320 may be configured to control the motor drive circuit 312 to rotate the motor 310 to adjust the present position P_PRES of the covering material between the fully-raised position P_RAISED and the fully-lowered position P_LOWERED. For example, the control circuit 320 may be configured to adjust the present position P_PRES of the covering material through a full-raise movement (e.g., from the fully-lowered position P_LOWERED to the fully-raised position P_RAISED) and a full-lower movement (e.g., from the fully-raised position P_RAISED to the fully-lowered position P_LOWERED). The control circuit 320 may be configured to monitor the magnitude of the input power P_IN of the motor drive unit 300 while adjusting the present position P_PRES of the covering material through the full-raise movement and the full-lower movement.

The control circuit 320 may be configured to determine a result of the test procedure by comparing the magnitude of the input power P_IN to the one or more power thresholds while the control circuit 320 is controlling the motor drive circuit 312 to adjust the present position P_PRES of the covering material during the test procedure. The control circuit 320 may be configured to determine that the window treatment system requires at least one more lift assistance spring when the input power P_IN of the motor drive unit exceeds a raise-movement power threshold P_TH-RAISE when the control circuit 320 is controlling the motor drive circuit 312 to raise the covering material during the full-raise movement. The control circuit 320 may be configured to determine that the window treatment system requires at least one less lift assistance spring when the input power P_IN of the motor drive unit exceeds a lower-movement power threshold P_TH-LOWER when the control circuit is controlling the motor drive circuit 312 to lower the covering material during the full-lower movement. The control circuit 320 may be configured to determine that the window treatment system is appropriately spring-balanced when the magnitude of the input power P_IN of the motor drive unit does not exceed the raise-movement power threshold P_TH-RAISE when the control circuit is controlling the motor drive circuit 312 to raise the covering material during the full-raise movement or the input power P_IN of the motor drive unit does not exceed the lower-movement power threshold P_TH-LOWER when the control circuit 312 is controlling the motor drive circuit 312 to lower the covering material during the full-lower movement. For example, the raise-movement power threshold P_TH-RAISE may be equal to the lower-movement power threshold P_TH-LOWER.

The control circuit 320 may be configured to communicate an indication of the result of the test procedure (e.g., an indication that the window treatment system is appropriately spring-balanced, the window treatment system requires more lift assistance springs, or the window treatment system requires less lift assistance springs). The control circuit 320 may be configured to communicate an indication of the result of the test procedure by illuminating the light source 328 to provide the indication of the result of the test procedure. For example, the control circuit 320 may be configured to blink the light source 328 with a unique blink sequence (e.g., pattern) to indicate each of the different results of the test procedure (e.g., the window treatment system is appropriately spring-balanced, requires more lift assistance springs, or requires less lift assistance springs). Additionally or alternatively, the control circuit 320 may be configured to communicate the indication of the result of the test procedure by transmitting a message (e.g., including the indication of the result of the test procedure) via the communication circuit 325. Further, the control circuit 320 may be configured to communicate the indication of the test procedure by stopping movement of the covering material of the window treatment system and/or wiggling the covering material (e.g., quickly raising and lowering the covering material between two positions).

FIG. 17 is a flowchart of an example test procedure 400 for verifying proper spring-balancing of a window treatment system (e.g., the Roman shade system 100 shown in FIGS. 1-3). The test procedure 400 may be executed by a control circuit (e.g., the control circuit 320) of a motor drive unit (e.g., the motor drive unit 160, 300). The motor drive unit may comprise a motor (e.g., the motor 310) configured to rotate a roller tube (e.g., the roller tube 122) of the window treatment system for adjusting a present position P_PRES of a covering material (e.g., the shade fabric 102) between a fully-lowered position P_LOWERED and a fully-raised position P_RAISED. The motor drive unit may be powered by one or more batteries (e.g., the batteries 154, 360). The window treatment system may comprise a lift assistance subsystem (e.g., the lift assistance subsystem 180) having one or more lift assistance springs (e.g., the lift assistance springs 182) for assisting the motor drive unit in raising and lowering the covering material. The test procedure 400 may be executed by the control circuit during a fabrication procedure (e.g., at 222 of the fabrication procedure 200) of the window treatment system. The test procedure 400 may be initiated by a technician (e.g., the technician carrying out the fabrication procedure 200). In addition, the test procedure 400 may be executed by the control circuit after installation of the window treatment system as the final installation site, and/or executed periodically as a maintenance process to determine if the spring-balancing of the window treatment system has changed over time.

The control circuit may start the test procedure 400 at 410 in response to receiving an input from the technician. For example, the control circuit may start the test procedure 400 at 410 in response to detecting an actuation of a button of the motor drive unit (e.g., the button on the end portion 165 of the motor drive unit 160 and/or the buttons that actuate the switching devices of the actuator circuit 326). In addition, the control circuit may start the test procedure 400 at 410 in response to receiving a message (e.g., in one or more wireless signals, such as radio-frequency signals) via a communication circuit (e.g., the communication circuit 325).

At 412, the control circuit may control a motor drive circuit to drive a motor (e.g., the motor 310) to adjust the present position P_PRES of the covering material to the lowered position P_LOWERED. For example, the control circuit may be configured to automatically adjust the present position P_PRES of the covering material to the fully-lowered position P_LOWERED after the test procedure 400 is started. In some examples, the technician may manually adjust the present position P_PRES of the covering material to the lowered position P_LOWERED prior to the start of the test procedure 400 (e.g., adjustment of the covering material at 412 may be omitted from the test procedure 400).

At 414, the control circuit may begin moving (e.g., automatically begin moving) the covering material to the fully-raised position P_RAISED (e.g., to start a full-raise movement of the covering material). For example, the control circuit may set a destination position P_DEST equal to the fully-raised position P_RAISED at 414. At 416, the control circuit may sample one or more sense signals of the motor drive unit during the movement, for example, using one or more analog-to-digital converters (ADCs). For example, the control circuit may sample a battery-voltage sense signal V_V-BATT that may indicate a magnitude of a battery voltage V_BATT produced by the batteries to generate a battery-voltage sample S_V-BATT at 416. In addition, the control circuit may sample a battery-current sense signal V_I-BATT that may indicate a magnitude of a battery current I_BATT conducted through the batteries generate a battery-current sample S_I-BATT at 416.

At 418, the control circuit may determine a magnitude of an input power P_IN of the motor drive unit (e.g., a power consumed from the batteries) based on the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT. For example, the control circuit may be configured to calculate the magnitude of the input power P_IN by multiplying the battery-voltage sample S_V-BATT by the battery-current sense signal S_I-BATT, e.g., P_IN=(α·S_v-BATT)·(β·S_I-BATT), where a and B are coefficients having values dependent upon the electrical circuitry used to generate the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT, respectively. In some examples, the control circuit may determine the magnitude of the input power P_IN of the motor drive unit (e.g., a power consumed from the batteries) based on (e.g., based on only) the battery-current sense signal V_I-BATT (e.g., not based on the battery-voltage sense signal V_V-BATT). For example, the control may assume that the magnitude of the battery voltage V_BATT is a predetermined constant value, and calculate the magnitude of the input power P_IN by multiplying the predetermined constant value of the battery voltage V_BATT by the battery-current sense signal S_I-BATT.

At 420, the control circuit may determine if the magnitude of the input power P_IN is greater than or equal to a power threshold P_TH while the control circuit is moving the covering material (e.g., raising the covering material as started at 414). For example, the control circuit may set the power threshold P_TH equal to a raise-movement power threshold P_TH-RAISE when the control circuit is raising the covering material during the full-raise movement, and equal to a lower-movement power threshold P_TH-LOWER when the control circuit is lowering the covering material during the full-lower movement. The raise-movement power threshold P_TH-RAISE may be, for example, equal to the lower-movement power threshold P_TH-LOWER. In some examples, the control circuit may compare the magnitude of the battery current I_BATT (e.g., the battery-current sample S_I-BATT) to a current threshold (e.g., if the control circuit is not configured to receive the battery-voltage sense signal V_V-BATT).

When the magnitude of the input power P_IN is not greater than or equal to the power threshold P_TH at 420, the control circuit may determine if the covering material is at the destination position P_DEST (e.g., as set at 414) at 422. For example, the control circuit may determine that the covering material is at the destination position P_DEST if the present position P_PRES of the covering material is equal to the destination position P_DEST at 422. When the covering material is not at the destination position P_DEST at 422, the control circuit may continue to sample the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT at 416 and calculate the input power P_IN of the motor drive unit at 418.

When the magnitude of the input power P_IN is greater than or equal to the power threshold P_TH (e.g., the raise-movement power threshold P_TH-RAISE) at 420 and the control circuit is presently raising the covering material at 424, the control circuit may at 426 store in memory (e.g., the memory 324) an indication that the magnitude of the input power P_IN exceeded the power threshold P_TH during the test procedure 400 (e.g., that the window treatment system is not spring-balanced). For example, the control circuit may store in memory at 426 an indication that too few lift assistance springs are installed in the window treatment system at 426. In addition, the control circuit may communicate an indication that too few lift assistance springs are installed at 426. For example, the control circuit may illuminate a visible indicator (e.g., by illuminating the light source 328) to blink the visible indicator with a unique blink sequence that indicates that too few lift assistance springs are installed. Additionally or alternatively, the control circuit may transmit a message including the indication that too few lift assistance springs are installed at 426 (e.g., via a communication circuit 325). After storing in memory the indication that too few lift assistance springs are installed at 426, the control circuit may again sample the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT at 416 and calculate the input power P_IN of the motor drive unit at 418.

When the covering material is at the destination position P_DEST at 422, the control circuit may determine at 430 if the control circuit is done with movements for the test procedure 400 (e.g., if the control circuit has moved the covering material through both the full-raise movement and the full-lower movement during the test procedure 400). If the control circuit is not done with movements (e.g., if the control circuit has only moved the covering material through the full-raise movement) at 430, the control circuit may begin moving the covering material to the fully-lowered position P_LOWERED (e.g., to start a full-lower movement of the covering material) at 432. For example, the control circuit may set a destination position P_DEST equal to the fully-lowered position P_LOWERED at 432. During the full-lower movement, the control circuit may sample the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT at 416 and calculate the input power P_IN of the motor drive unit at 418.

When the magnitude of the input power P_IN is greater than or equal to the power threshold P_TH at 420 and the control circuit is presently lowering the covering material at 424, the control circuit may store in memory an indication that too many lift assistance springs are installed in the window treatment system at 428. In addition, the control circuit may communicate at 428 an indication that too many lift assistance springs are installed (e.g., an indication that the magnitude of the input power P_IN exceeded the power threshold P_TH during the test procedure 400). For example, the control circuit may blink the visible indicator with a unique blink sequence that indicates that the window treatment system requires less lift assistance springs. Additionally or alternatively, the control circuit may transmit a message including the indication that too many lift assistance springs are installed at 428 (e.g., via a communication circuit 325). After storing in memory the indication that too many lift assistance springs are installed at 428, the control circuit may again sample the battery-voltage sense signal V_V-BATT and the battery-current sense signal V_I-BATT at 416 and calculate the input power P_IN of the motor drive unit at 418.

When the covering material is at the destination position P_DEST (e.g., the fully-lowered position P_LOWERED) at 422 and the control circuit is done with movements at 430, the control circuit may determine at 434 if there is stored in memory an indication that too few lift assistance springs are installed in the window treatment system. When there is an indication that too few lift assistance springs are installed at 434, the control circuit may communicate at 436 an indication that too few lift assistance springs are installed in the window treatment system (e.g., an indication that the magnitude of the input power P_IN exceeded the power threshold P_TH during the full-raise movement of the test procedure 400), before the test procedure 400 ends at 444. For example, the control circuit may blink the visible indicator with a unique blink sequence that indicates that too few lift assistance springs are installed at 436. Additionally or alternatively, the control circuit may transmit a message including the indication that too many lift assistance springs are installed at 436 (e.g., via a communication circuit 325).

When there is not an indication that too few lift assistance springs are installed at 434, but there is an indication that too many lift assistance springs are installed at 438, the control circuit may communicate an indication that too many lift assistance springs are installed at 440 (e.g., an indication that the magnitude of the input power P_IN exceeded the power threshold P_TH during the full-lower movement of the test procedure 400), before the test procedure 400 ends at 444. For example, the control circuit may blink the visible indicator with a unique blink sequence that indicates that too many lift assistance springs are installed at 440. When there is not an indication that too few lift assistance springs are installed at 434 or an indication that too many lift assistance springs are installed at 438, the control circuit may communicate an indication that the window treatment system is spring-balanced at 442 (e.g., by causing the visible indicator to blink a unique blink sequence and/or transmitting a message), before the test procedure 400 ends at 444. In some examples, the test procedure 400 may simply end at 444 when there is not an indication that too few lift assistance springs are installed at 434 or an indication that too many lift assistance springs are installed at 438 (e.g., the control circuit may not communicate an indication that the window treatment system is spring-balanced at 442).

While the test procedure 400 has been described with the control circuit automatically controlling the covering material from the fully-lowered position P_LOWERED to the fully-raised position P_RAISED at 414 and automatically controlling the covering material from the fully-raised position P_RAISED to the fully-lowered position P_LOWERED at 432, the test procedure 400 may also be implemented with the technician manually causing the motor drive unit to move the covering material at 414 and 432. For example, the technician may cause the motor drive unit to start the test procedure at 410 (e.g., to enter a test mode) by actuating a button on a remote control device and actuating other buttons on the remote control device to cause the motor drive unit to move through the full-raise movement and/or the full-lower movement.

FIGS. 18A and 18B depict an illustrative lift assistance subsystem 1800, such as lift assistance subsystem 180 depicted above in FIG. 14) in accordance with one or more embodiments described herein. Lift assistance subsystem 1800 may include one or more lift assistance springs 1802 (one shown). FIG. 18A is an exploded view of an illustrative lift assistance subsystem 1800 that includes a lift assistance spring 1802 that reversibly travels between a flanged drive drum 1804 and a flanged storage drum 1806. The flanged drive drum 1804 and the flanged storage drum 1806 are disposed in a housing that includes a first enclosure portion 1810A configured to be couplable to a second enclosure portion 1810B. Although flanges are depicted along both side edges of the flanged drive drum 1804 and the flanged storage drum 1806, in some implementations, the flanged drive drum 1804 and/or the flanged storage drum 1806 may include only a single flange disposed on one side edge. In embodiments, one or more latching features 1860 disposed on the first enclosure portion 1810A engage one or more respective complimentary recesses 1862 formed in the second enclosure portion 1810B. As depicted in FIG. 18A, in at least some instances, the first enclosure portion 1810A is identical to the second enclosure portion 1810B. In other instances, differences may exist between the first enclosure portion 1810A and the second enclosure portion 1810A. Lift assistance subsystem 1800 may include a shaft 1808. The shaft 1808 is operatively coupled to the flanged drive drum 1804 and extends at least partially through an aperture formed in the first enclosure portion 1810A. The second enclosure portion 1810B also includes an aperture formed therein that allows access to an aperture in the flanged drive drum 1804. In embodiments, multiple lift assistance subsystems 1800 may be “stacked” and operatively coupled together—in such instances, the flanged drive drum of a second lift assistance subsystem accepts via the aperture formed in the flanged drive drum of the second lift assistance subsystem the insertion of the shaft 1808 from an immediately adjacent first lift assistance subsystem 1800 through the aperture 1828 formed in the second enclosure portion 1810B of the second lift assistance subsystem, thereby mechanically and operatively coupling the first and the second lift assistance subsystems 1800 together to provide additional lifting capability for larger window treatments and/or window treatments using heavier fabrics or materials. In such instances, one or more multi-unit latching members 1850 disposed on an external surface of the housing 1810 engage one or more complimentary recesses 1852 disposed on an external surface of an adjacent lift assistance subsystem. The flanges 1834 on the flanged drive drum 1804 and the flanges 1836 on the flanged storage drum 1806 align the lift assistance spring 1802 on each drum as the lift assistance spring 1802 travels between the drums.

The lift assistance spring 1802 includes a pre-stressed flat strip of material formed into nearly constant radius coils around itself. In embodiments, the lift assistance spring 1802 is attached or otherwise affixed to the flanged drive drum 1804. In embodiments, the lift assistance spring 1802 is attached or otherwise affixed to the flanged storage drum 1806. In yet other embodiments, the lift assistance spring 1802 is attached or otherwise affixed to both the flanged drive drum 1804 and the flanged storage drum 1806 forming an “S”-shaped pattern between the drive drum 1804 and the storage drum 1806. In embodiments, the lift assistance spring 1802 may be affixed to the flanged drive drum 1804 and the flanges storage drum 1806 using a mechanical fastener, an adhesive, or a mechanical interference fit (e.g., disposed in a slot formed in the drum core). The lift assistance spring 1802 coils around and travels between the flanged drive drum 1804 and flanged storage drum 1806. The lift assistance spring follows an “S”-shaped travel path between the drums. The lift assistance spring 1802 is used to reduce the power required to raise a motorized window treatment from a lowered position to a raised position. When the motorized window treatment system is in the raised position, the lift assistance spring 1802 coils about the flanged storage drum 1806. To lower a motorized window treatment, a motor or other driver causes the flanged drive drum 1804 to rotate in a first direction (e.g., counter-clockwise). Rotating the flanged drive drum 1804 in the first direction causes the lift assistance spring 1808 to uncoil from the flanged storage drum 1806 and coil about the flanged drive drum 1804. To raise the motorized window treatment, the motor causes the flanged drive drum 1804 to rotate in a second direction (e.g., clockwise). Rotating the flanged drive drum 1804 in the second direction causes the lift assistance spring 1808 to exert a rotational force on the flanged drive drum 1804 as the spring uncoils from the flanged drive drum 1804 and coils about the flanged storage drum 1806. The lift assistance spring 1802 thus provides an overall net reduction in the power input requirement of the motor to raise the motorized window treatment. The reduction in power input requirement resulting from the use of the lift assistance spring 1802 beneficially improves battery life for battery powered motorized window treatments, for example. The flanges on the flanged drive drum 1804 and the flanged storage drum 1808 contact the opposing edges of the 1840, 1842 lift assistance spring 1802, thereby aligning the spring as it coils about the respective drum. In such installations, while lift assistance spring 1802 beneficially reduces the power input requirement of the motor, the contact between the edges of the lift assistance spring 1802 and the flanges on the flanged drive drum 1804 and the flanged storage drum 1806 increase the power input requirement provided by the motor to overcome friction between the lift assistance spring 1802 and the flanged drive drum 1804 and the flanged storage drum 1808.

FIG. 18B is a cross-sectional view along sectional line B-B (ref. FIG. 18A) of the assembled illustrative lift assistance subsystem 1800 depicted in FIG. 18A. As depicted in FIG. 18B, an axial support portion 1814 of the flanged drive drum 1804 is supported by bearing surfaces 1824 formed by the assembled first enclosure portion 1810A and second enclosure portion 1810B. Similarly, an axial support portion 1816 of the flanged storage drum 1806 is supported by bearing surfaces 1826 formed by the assembled first enclosure portion 1810A and second enclosure portion 1810B. Assembling the first enclosure portion 1810A and second enclosure portion 1810B traps the flanged drive drum 1804, the flanged storage drum 1806, and the lift assistance spring 1802 within a enclosure 1810 formed by joining the first enclosure portion 1810A and the second enclosure portion 1810B.

In operation, the inherent coiling property of the lift assistance spring 1802 causes the spring to coil around the flanged storage drum 1806 in the absence of externally applied torque to the flanged drive drum 1804. Application of a rotational force in a first direction to the flanged drive drum 1804 (e.g., a counter-clockwise direction to lower a motorized window treatment) causes the lift assistance spring 1802 to travel from the flanged storage drum 1806 to the flanged drive drum 1804 (i.e., uncoil from the flanged storage drum 1806 and coil about the flanged drive drum 1804). Application of a rotational force in a second direction to the flanged drive drum 1804 (e.g., a clockwise direction to raise a motorized window treatment) causes the lift assistance spring 1802 to travel from the flanged drive drum 1804 to the flanged storage drum 1806 (i.e., uncoil from the flanged storage drum 1806 and coil about the flanged drive drum 1804).

In motorized window treatment applications such as Roman shades where the weight of the fabric increases as the shade is raised a gradient-negative lift assistance spring is used for the lift assistance spring 1802. The torque applied to the flanged drive drum 1804 by a gradient-negative lift spring increases as the lift assistance spring 1802 uncoils from the flanged drive drum 1802, thereby decreasing the required power input from the motor drive unit to raise the Roman shade, this is particularly advantageous since the weight of the Roman shade increases while raising.

While the flanges 1834 present on the flanged drive drum 1804 and the flanges 1836 present on the flanged storage drum 1806 beneficially maintain the alignment of the lift assistance spring 1802 on each drum, the presence of the flanges 1834, 1836 on both the drive drum 1804 and storage drum 1806 has been found to cause an objectionable level of noise as the lift assistance spring 1802 travels between the drums when the motorized window treatment is raised or lowered.

FIG. 19A is an exploded view of another illustrative lift assistance subsystem 1900 that may include a gradient-negative lift assistance spring 1902 that reversibly travels between a drive drum 1904 and a flanged storage drum 1906 as similarly described for lift assistance subsystem 1800. The flangeless drive drum 1902 and the flanged storage drum 1904 are disposed in an enclosure 1910 formed by physically coupling a first enclosure portion 1910A to a second enclosure portion 1910B. As used herein the term “flangeless” refers to a drum that lacks an extension perpendicular to at least one side edge of the surface of the drum that carries the lift assistance spring. As depicted in FIG. 19A, in at least some implementations, the first enclosure portion 1910A is identical to the second enclosure portion 1910B. In the implementation depicted in FIG. 19A, the interior or inside surface of the first enclosure portion 1910A and the interior surface the second enclosure portion 1910B each include a plurality of bumpers 1920A-1920n (collectively, “bumpers 1920”; two (2) bumpers 1920A, 1920B in each enclosure portion 1910 are depicted in FIG. 19A) (bumper 1920A of enclosure 1910B is not shown in FIG. 19A). In embodiments, the bumpers 1920 may be disposed on both the first enclosure portion 1910A and the second enclosure portion 1910B. In other embodiments, the bumpers may be disposed on only one enclosure portion (i.e., on either the first enclosure portion 1910A or the second enclosure portion 1910B). The bumpers 1920 guide the lift assistance spring 1902 as the spring coils on and/or uncoils from the drive drum 1904. The bumpers 1920 on the enclosure 1910 and the flanges 1916A and 1916B on the flanged storage drum 1906 cooperate to align the lift assistance spring 1902 with the drive drum 1904 and the storage drum 1906 as the lift assistance spring 1902 travels between the drums. A first end of the lift assistance spring 1902 physically couples to the flanged storage drum 1906 and a second end of the lift assistance spring 1902 physically couples to the drive drum 1904, such that the lift assistance spring 1902 does not “unwind” or physically decouple from either the drive drum 1904 or the flanged storage drum 1906.

In the embodiment depicted in FIG. 19A, each side of the flanged storage drum 1906 includes flanges 1916A, 1916B (collectively, “flanges 1916”) on opposing side of the drum. In embodiments, the flanges 1916 are formed integral with the flanged storage drum 1906, for example via injection molding. The flanges 1916A, 1916B can have the same or different heights measured with respect to the surface of the flanged storage drum 1906. In at least some implementations, the height of flanges 1916 is greater than the depth of lift assistance spring 1902 when coiled on the flanged storage drum 1906 (i.e., when the length of lift assistance spring 1920 on the drive drum 1904 is minimized).

As depicted in FIG. 19A, each of the enclosure portions 1910A, 1910B includes a plurality of bumpers 1920 disposed about the aperture 1912 into which the flangeless drive drum 1902 is inserted. In the embodiment depicted in FIG. 19A, two bumpers 1920A and 1920B are disposed in each respective one of the enclosure portions 1910A and 1910B. Also as depicted in FIG. 19A, in at least some instances the bumpers 1920 are formed integral with, and consequently fabricated using the same material as, the enclosure portion 1910. In other instances, the bumpers 1920 may be formed separate from the enclosure portion 1910 and attached or otherwise affixed to the interior surface of the enclosure portion 1910. In instances where the bumpers 1920 are formed separate from the enclosure portion 1910, the bumpers 1920 may be fabricated using the same material as the enclosure portion 1910 or fabricated using a material different from the enclosure portion 1910. The drive drum 1904 includes a collar 1942 that projects from each side of the drive drum 1904 and is parallel to an axial centerline of the drive drum 1904. The collar 1942 fits within and is supported by the aperture 1828 formed in the first enclosure portion 1910A and the second enclosure portion 1910B. Similarly, the flanged storage drum 1906 includes a stub shaft 1944 that projects from each side of the flanged storage drum 1906 and is parallel to an axial centerline of the flanged storage drum 1906. The stub shaft fits within and is supported by an aperture 1946 formed in the first enclosure portion 1910A and the second enclosure portion 1910B.

FIG. 19B is a cross-sectional view of the illustrative lift assistance subsystem 180 depicted in FIG. 19A along section line B-B. FIG. 19B more clearly depicts the bumpers 1920A, 1920B in each enclosure portion 1910A and 1910B that maintain alignment of the lift assistance spring 1902 on the drive drum 1904. Physically coupling the first enclosure portion 1910A with the second enclosure portion 1910B traps the drive drum 1904, the flanged storage drum 1906, and the lift assistance spring 1902 within the enclosure 1910. When physically coupled, gaps 1930 exists between the edges 1952 of the lift assistance spring 1902 and each of the bumpers 1920A and 1920B such that when the lift assistance spring is centered on the drive drum 1904, the edges of the lift assistance spring do not contact either of the bumpers 1920A, 1920B. The gap 1930 between the edges of the lift assistance spring 1902 and each of the bumpers 1920A, 1920B is: about 0.010 inches or less; about 0.020 inches or less; about 0.030 inches or less; about 0.040 inches or less; or about 0.050 inches or less. In at least one embodiment, the gap 1930 between the edges of the lift assistance spring 1902 and each of the bumpers 1920A, 1920B is about 0.040 inches. As used herein, the term “about” includes a range of values that extend from 80% of the stated value to +120% of the stated value.

In embodiments such as depicted in FIG. 19B, the drive drum 1904 can be a flangeless drive drum that does not include flanges on either side of the drive drum 1904. In other embodiments, the drive drum 1904 may include only a partial flange on either one or both sides of the drive drum. A partial flange has a flange height less than the depth of the lift assistance spring 1902 on the drive drum when the length of lift assistance spring 1920 on the flanged storage drum 1906 is minimized and/or the length of the lift assistance spring 1920 on the drive drum is maximized. For example, in embodiments, the drive drum 1904 may include a partial flange having a height of: about 10% or less; about 25% or less; about 50% or less; about 75% or less; or about 90% or less of the depth of the lift assistance spring 1902 on the drive drum when the length of lift assistance spring 1920 on the flanged storage drum 1906 is minimized.

FIG. 19C is an elevation of an illustrative enclosure portion 1910 with the lift assistance spring 1902, the drive drum 1904, and the flanged storage drum 1906 removed to better show the bumpers 1920A, 1920B disposed, formed, or otherwise attached to an internal surface of the enclosure portion 1910. In the embodiment depicted in FIG. 19C, the first bumper 1920A is disposed at about +120°, or about 4 o'clock position, with respect to the drive drum 1904 and the second bumper 1920B is positioned at about −120° (i.e., the “8 o'clock” position) with respect to the longitudinal axis 1940 of the enclosure portion 1910. Although only two bumpers 1920A, 1920B are depicted in FIG. 19C, in other embodiments, each of the enclosure portions 1910A, 1910B may include a lesser or greater number of bumpers 1920A-1920n and/or different bumper locations.

As depicted in FIG. 19C, each of the bumpers 1920A, 1920B may include a generally trapezoidal, raised, portion of the enclosure portion 1910. Each bumper 1920 extends radially outward from a location proximate the aperture 1912 formed in the first enclosure portion 1910A and the second enclosure portion 1910B. The lateral deviation of the lift assistance spring 1902 on the drive drum 1904 is limited by the bumpers 1920. In other words, the bumpers 1920 maintain the lateral alignment of the lift assistance spring 1902 with respect to the drive drum 1904. In operation, if the lift assistance spring maintains alignment with the drive drum 1904, the lift assistance spring 1902 will not contact the bumpers 1920A, 1920B. If the alignment of the lift assistance spring 1902 does deviate with respect to the drive drum 1904, the edge of the lift assistance spring 1902 will contact only one of the bumpers, either 1920A or 1920B dependent on the direction of the deviation. In either case (no deviation/no bumper contact, deviation/contact with 1 bumper) the lift assistance spring contacts an external surface on only one edge. In contrast, if a flanged drive drum 1904 is used, both edges of the lift assistance spring 1902 may contact the flanges, increasing the operational noise when compared to the operational noise of the flangeless drive drum 1904, such as depicted in FIGS. 19A-19D.

FIG. 19D is a cross-sectional view of the illustrative lift assistance subsystem 1900 depicted in FIG. 19A along sectional line D-D. that shows the location of the bumpers 1910 disposed in the enclosure portion 1906 with respect to the drive drum 1904. As depicted in FIG. 19D a first bumper 1920A is positioned at about −120° (i.e., the “8 o'clock” position) with respect to the longitudinal centerline 1940 of the enclosure 1910. Also as depicted in FIG. 19D, a second bumper 1910B is positioned at about +120° (i.e., the “4 o'clock” position) with respect to the longitudinal centerline 1940 of the enclosure 1910. Any number of bumpers 1920 may be formed, attached, coupled, with or otherwise disposed on the interior surfaces of either or both enclosure portions 1910A, 1910B. Similarly, the bumpers 1920 may be distributed evenly or unevenly (e.g., as depicted in FIGS. 19A-19D) about the circumference or perimeter of the drive drum 1902. For example, in a different embodiment, bumpers 1920A and 1920B may be disposed at the 90° angles (i.e., the 3 o'clock and 9 o'clock positions) with respect to the longitudinal centerline 1940 of the enclosure 1910. While the bumpers 1920 may be disposed at any angular orientation with respect to the longitudinal centerline 1940 of enclosure 1910, it has been found that positioning the bumpers at the 4 o'clock and 8 o'clock positions provides a satisfactory reduction in power input requirement and also a satisfactory reduction in operational noise when compared with lift assistance subsystems 1800 having a flanged drive drum 1804 and a flanged storage drum 1806.

While the flanges present on the flanged drive drum 1804 and the flanged storage drum 1806, such as depicted in FIGS. 18A and 18B beneficially maintain the alignment of the lift assistance spring 1802 on each drum, the presence of the flanges on both the drive drum 1804 and storage drum 1806 has been found to detrimentally increase the friction between the lift assistance spring 1802 and each drum as the lift assistance spring 1802 travels between the drums during normal operation. Further, the friction between the lift assistance spring 1802 and the flanges on the drive drum 1804 and storage drum 1806 has been found to create a human perceptible, objectionable, level of operational noise. The increase in friction caused by the flanged drive drum 1804 and the flanged storage drum 1804 increases the power input required to raise and lower an operationally coupled window treatment. In battery powered motorized window treatment installations, such increased power input requirements have been found to significantly impact battery life, resulting in more frequent battery changes.

In alternate embodiments, a possibility exists to use a motorized window treatment lift assistance subsystem 180 that includes a flanged drive drum and a storage drum with minimal or no flanges. Such a system would use bumpers 1920 similar to those depicted in FIGS. 19A-19D, positioned proximate the storage drum rather than the drive drum as depicted in FIGS. 19A-19D. For example, the bumpers 1920 in a lift assistance subsystem 180 using a flanged drive drum and a storage drum may be disposed at an angle of about −60° (i.e., the 10 o'clock position) and +60° (i.e., the 2 o'clock position) measured with respect to the longitudinal centerline 1940 of the enclosure 1910. A lift assistance subsystem using a flanged drive drum and a storage drum has been found to beneficially offer a reduced power input requirement and reduced operational noise when compared to lift assistance subsystems using a flanged drive drum and a flanged storage drum. However, the reduction in input power requirement and operational noise provided by a flanged drive drum and flangeless storage drum system is less than the reductions in input power and operational noise when compared to the drive system described in FIGS. 19A-19D.

Although the present disclosure has been described in relation to particular examples thereof, many other variations and modifications and other uses will become apparent to those skilled in the art. For example, although the kits, systems, and methods have been described in relation to Roman shades, it should be understood that the concepts may be applied to other types of window treatments, such as Venetian blinds and cellular shades, to list only a couple of possibilities.

Claims

1. A window treatment system comprising: a motor drive unit operatively coupled to the covering material for adjusting the covering material between a fully-lowered position and a fully-raised position;a lift assistance subsystem couplable to the motor drive unit, the lift assistance subsystem configured to provide variable lift assistance to the motor drive unit, the lift assistance subsystem including: a lift assistance spring having a first end and a second end;a drive drum coupled to the first end of the lift assistance spring;a storage drum coupled to the second end of the lift assistance spring;a housing disposed about the lift assistance spring, the drive drum, and the storage drum, the housing including:a plurality of bumpers disposed proximate at least one side of at least one of: the drive drum or the storage drum, each of the plurality of bumpers positioned to align the lift assistance spring with at least one of: the drive drum or the storage drum.

2. The window treatment system of claim 1 wherein each of the plurality of bumpers are formed integral with the housing.

3. The window treatment system of claim 1 wherein the lift assistance spring comprises a lift assistance gradient spring.

4. The window treatment system of claim 3 wherein the lift assistance gradient spring comprises a lift assistance negative-gradient spring.

5. The window treatment system of claim 1 wherein the storage drum includes a flange having a first height disposed on at least one side of the storage drum and the drive drum includes a flange having a second height less than the first height.

6. The window treatment system of claim 1 wherein the storage drum includes a flange having a first height disposed on at least one side of the storage drum and the drive drum includes a flangeless drive drum.

7. The window treatment system of claim 6 wherein the plurality of bumpers includes: a first bumper disposed proximate the drive drum and at an angle of about −120° measured with respect to a longitudinal centerline of the housing; anda second bumper disposed proximate the drive drum at an angle of about +120° measured with respect to a longitudinal centerline of the housing.

8. The window treatment system of claim 1 wherein the storage drum includes a flange having a first height disposed on at least one side of the storage drum and the drive drum includes a flange having a second height greater than the first height.

9. The window treatment system of claim 1 wherein the drive drum includes a flange having a first height disposed on at least one side of the drive drum; wherein the storage drum includes a drum that lacks an extension perpendicular to at least one side edge of the surface of the storage drum that carries the lift assistance spring.

10. The window treatment system of claim 9 wherein the plurality of bumpers includes: a first bumper disposed proximate the storage drum and at an angle of about −60° measured with respect to a longitudinal centerline of the housing; anda second bumper disposed proximate the storage drum at an angle of about +60° measured with respect to a longitudinal centerline of the housing.

11. A motorized window treatment system lift assistance method, comprising: causing a motor to rotate a drive drum in a first direction to transfer at least a portion of a gradient spring from a storage drum to the drive drum, responsive to an input to lower the motorized window treatment; wherein the storage drum and drive drum are disposed in a housing;guiding the gradient spring during the transfer from the storage drum to the drive drum using a plurality of bumpers disposed on an inner surface of the housing;causing the motor to rotate the drive drum in a second direction to return the gradient spring to the storage drum, responsive to an input to raise the motorized window treatment; andguiding the gradient spring during the return from the drive drum to the storage drum using a plurality of bumpers disposed on an inner surface of the housing.

12. The method of claim 11 wherein guiding the gradient spring during the transfer from the storage drum to the drive drum using the plurality of bumpers disposed on an inner surface of the housing further comprises: guiding the gradient spring during the transfer from the storage drum to the drive drum using the plurality of bumpers disposed on an inner surface of the housing, each of the plurality of bumpers formed integral with the housing.

13. The method of claim 12 wherein guiding the gradient spring during the transfer from the storage drum to the drive drum using the plurality of bumpers disposed on an inner surface of the housing further comprises: guiding the gradient spring during the transfer from the storage drum to the drive drum using the plurality of bumpers, the plurality of bumpers including: a first bumper formed integral with the housing and disposed proximate the drive drum at an angle of −120° measured with respect to a longitudinal centerline of the housing; anda second bumper formed integral with the housing and disposed proximate the drive drum at an angle of +120° measured with respect to the longitudinal centerline of the housing.

14. The method of claim 13 wherein causing the motor to rotate the drive drum in the first direction to transfer at least the portion of the gradient spring from the storage drum to the drive drum, further comprises: causing a motor to rotate a flangeless drive drum in a first direction to transfer at least the portion of a gradient spring from a flanged storage drum to the flangeless drive drum;wherein the flangeless drive drum includes a drum that lacks an extension perpendicular to at least one side edge of the surface of the drive drum that carries the lift assistance spring.

15. The method of claim 12 wherein guiding the gradient spring during the transfer from the storage drum to the drive drum using the plurality of bumpers disposed on an inner surface of the lift assistance subsystem housing further comprises: guiding the gradient spring during the transfer from the storage drum to the drive drum using the plurality of bumpers, the plurality of bumpers including: a first bumper formed integral with the housing and disposed proximate the storage drum at an angle of −60° measured with respect to a longitudinal centerline of the housing; anda second bumper formed integral with the housing and disposed proximate the storage drum at an angle of +60° measured with respect to the longitudinal centerline of the housing.

16. The method of claim 15 wherein causing the motor to rotate the drive drum in the first direction to transfer at least the portion of the gradient spring from the storage drum to the drive drum, further comprises: causing a motor to rotate a flanged drive drum in a first direction to transfer at least the portion of a gradient spring from a flangeless storage drum to the flanged drive drum; wherein the flangeless storage drum includes a drum that lacks an extension perpendicular to at least one side edge of the surface of the storage drum that carries the lift assistance spring.

17. The method of claim 11 wherein causing the motor to rotate the drive drum in the first direction to transfer at least the portion of the gradient spring from the storage drum to the drive drum, further comprises: causing the motor to rotate the drive drum in the first direction to transfer at least a portion of a negative-gradient spring from the storage drum to the drive drum.

18. A motorized window treatment lift assistance subsystem comprising: a lift assistance spring having a first end and a second end;a drive drum coupled to the first end of the lift assistance spring;a storage drum coupled to the second end of the lift assistance spring;a housing disposed about the lift assistance spring, the drive drum, and the storage drum, the housing including: one or more bumpers disposed proximate at least one side of at least one of: the drive drum or the storage drum, each of the one or more bumpers positioned to align the lift assistance spring with a respective one of: the drive drum or the storage drum.

19. The motorized window treatment lift assistance subsystem of claim 18 wherein each of the one or more bumpers integrally formed on an interior surface of the housing.

20. The motorized window treatment lift assistance subsystem of claim 18 wherein the one or more bumpers include a plurality of bumpers integrally formed on an interior surface of the housing.

21. The motorized window treatment lift assistance subsystem of claim 18 wherein the lift assistance spring comprises a lift assistance gradient spring.

22. The motorized window treatment lift assistance subsystem of claim 21 wherein the lift assistance gradient spring comprises a lift assistance negative-gradient spring.

23. The motorized window treatment lift assistance subsystem of claim 18 wherein the storage drum includes a flange having a first height disposed on at least one side of the storage drum and the drive drum includes a flange having a second height less than the first height.

24. The motorized window treatment lift assistance subsystem of claim 18 wherein the storage drum includes a flange having a first height disposed on at least one side of the storage drum and the drive drum includes a flangeless drive drum; wherein the flangeless drive drum includes a drum that lacks an extension perpendicular to at least one side edge of the surface of the drive drum that carries the lift assistance spring.

25. The motorized window treatment lift assistance subsystem of claim 24 wherein the one or more bumpers include: a first bumper disposed proximate the drive drum and at an angle of about −120° measured with respect to a longitudinal centerline of the housing; anda second bumper disposed proximate the drive drum at an angle of about +120° measured with respect to a longitudinal centerline of the housing.

26. The motorized window treatment lift assistance subsystem of claim 18 wherein the storage drum includes a flange having a first height disposed on at least one side of the storage drum and the drive drum includes a flange having a second height greater than the first height.

27. The motorized window treatment lift assistance subsystem of claim 18 wherein the drive drum includes a flange having a first height disposed on at least one side of the drive drum and the storage drum includes a flangeless storage drum; wherein the flangeless storage drum includes a drum that lacks an extension perpendicular to at least one side edge of the surface of the storage drum that carries the lift assistance spring.

28. The motorized window treatment lift assistance subsystem of claim 27 wherein the one or more bumpers include: a first bumper disposed proximate the storage drum and at an angle of about −60° measured with respect to a longitudinal centerline of the housing; anda second bumper disposed proximate the storage drum at an angle of about +60° measured with respect to a longitudinal centerline of the housing.

29. The motorized window treatment lift assistance subsystem of claim 18: wherein the housing includes an aperture to accommodate the passage of a drive shaft coupled to a motor drive unit; andwherein the drive drum includes an aperture to physically couple the drive drum to the drive shaft coupled to the motor drive unit.

30. The motorized window treatment lift assistance subsystem of claim 18 wherein the housing comprises: a first enclosure portion physically couplable to a second enclosure portion; wherein the first enclosure portion includes one or more latching members to physically engage a complimentary recess on the second enclosure portion; andwherein the first enclosure portion includes one or more recesses to physically engage a complimentary latching member on the second enclosure portion.

31. The motorized window treatment lift assistance subsystem of claim 30 wherein the housing further comprises: at least one multi-unit latching member extending from an external surface the housing to engage at least one recess on an external surface of a second housing; andat least one recess disposed on a surface of the housing to engage at least one multi-unit latching member disposed on the external surface of the second housing.