Patent Description:
Certain window shades available on the market may be provided with an electric motor that allows conveniently raising and lowering of the shade. The electric motor and its power source may be disposed in a head rail mounted at a top of a window frame. The electric motor may be coupled to multiple cord winding units, wherein each of the cord winding units has one suspension cord anchored to a bottom rail of the window shade. Documents <CIT>, <CIT> <CIT> respectively describe coverings for windows, such as Venetian blinds. A lift system of the covering described in <CIT> may include a lift rod coupled to lift stations including one or more lift spools for winding and unwinding, and a spring motor operatively coupled to the lift rod, with the lift rod and the spring motor configured to be positioned within an interior of a bottom rail. In particular, <CIT> discloses an actuating system for a window shade, comprising two cord winding assemblies, wherein each of the two cord winding assemblies comprises a housing having a first and a second end opposite to each other, and a cavity between the first and second ends; a first spool portion connected with a first suspension cord, and a second spool portion connected with a second suspension cord, the first and second spool portions being disposed in the cavity of the housing; and a transmission axle rotationally coupled to the first and second spool portions and extending outside the housing at least at the first end thereof, the transmission axle and the first and second spool portions being rotatable concurrently relative to the housing in a first direction for respectively winding the first and second suspension cords around the first and second spool portions, and in a second direction opposite to the first direction for respectively unwinding the first and second suspension cords from the first and second spool portions.

The aforementioned arrangement is not compact, which may not be suitable for window shades of more complex constructions, such as window shades including two adjustable rails.

The present application describes actuating systems for window shades that are compact and easy to install, and can address at least the foregoing issues.

According to the invention, an actuating system for a window shade is provided, including an electric motor and two cord winding assemblies. Each of the two cord winding assemblies includes a housing, a first and a second spool portion respectively connected with a first and a second suspension cord, and a transmission axle. The housing has a first and a second end opposite to each other, and a cavity between the first and second ends. The first and second spool portions are disposed in the cavity of the housing. The transmission axle is rotationally coupled to the first and second spool portions and extends outside the housing at least at the first end thereof, the transmission axle and the first and second spool portions being rotatable concurrently relative to the housing in a first direction for respectively winding the first and second suspension cords around the first and second spool portions, and in a second direction opposite to the first direction for respectively unwinding the first and second suspension cords from the first and second spool portions. The two cord winding assemblies are respectively disposed at two opposite sides of the electric motor unit, the electric motor unit being respectively coupled to the transmission axle of each of the two cord winding assemblies.

According to an embodiment, a window shade includes a head rail, a bottom rail, an intermediate rail disposed between the head rail and the bottom rail, a shading structure disposed between the bottom rail and the intermediate rail, and the aforementioned actuating system assembled with the head rail, wherein the first and second suspension cords of one of the two cord winding assemblies are anchored to the bottom rail, and the first and second suspension cords of the other one of the two cord winding assemblies are anchored to the intermediate rail.

<FIG> is a perspective view illustrating an embodiment of a window shade <NUM>, and <FIG> is an exploded view of the window shade <NUM>. Referring to <FIG> and <FIG>, the window shade <NUM> can include a head rail <NUM>, a bottom rail <NUM>, an intermediate rail <NUM> disposed between the head rail <NUM> and the bottom rail <NUM>, a shading structure <NUM> disposed between the bottom rail <NUM> and the intermediate rail <NUM>, and an actuating system <NUM>.

The head rail <NUM> may be affixed at a top of a window frame, and can have any desirable shapes. According to an example of construction, the head rail <NUM> can have an elongate shape including a cavity for at least partially receiving the actuating system <NUM> of the window shade <NUM>. For example, the head rail <NUM> can include a rail part <NUM> having an inner cavity that is respectively closed at two opposite ends with two end caps <NUM>, and a cover <NUM> attached to a front of the rail part <NUM>.

The bottom rail <NUM> can be suspended from the head rail <NUM> with at least two suspension cords <NUM> and <NUM>, wherein the two suspension cords <NUM> and <NUM> can respectively have ends 118A and 120A anchored to the bottom rail <NUM>. According to an example of construction, the bottom rail <NUM> may have a channel adapted to receive to the attachment of the shading structure <NUM>.

The intermediate rail <NUM> can be disposed between the head rail <NUM> and the bottom part <NUM>, and can be suspended from the head rail <NUM> with at least two other suspension cords <NUM> and <NUM>, wherein the other two suspension cords <NUM> and <NUM> can respectively have ends 118B and 120B anchored to the intermediate rail <NUM>. The intermediate rail <NUM> may also have an elongate shape having a channel adapted to receive an attachment of the shading structure <NUM>. Moreover, a plurality of guiding elements <NUM> may be provided in the intermediate rail <NUM> for facilitating the passage of the suspension cords <NUM> and <NUM> that are anchored to the bottom rail <NUM> through the intermediate rail <NUM>. The guiding elements <NUM> may exemplary include grommets affixed to the intermediate rail <NUM>.

The shading structure <NUM> may exemplary have a cellular structure, which may include, without limitation, honeycomb structures. However, it will be appreciated that the shading structure <NUM> may have any suitable structure that can be expanded and collapsed between the bottom rail <NUM> and the intermediate rail <NUM>. The shading structure <NUM> has two opposite ends 108A and 108B respectively disposed adjacent to the intermediate rail <NUM> and the bottom rail <NUM>. For example, the end 108A of the shading structure <NUM> may be provided with a strip <NUM> that is engaged with the intermediate rail <NUM> so as to attach the end 108A of the shading structure <NUM> to the intermediate rail <NUM>, and the other end 108B of the shading structure <NUM> may be likewise attached to the bottom rail <NUM> via a strip <NUM>. Two end caps <NUM> may respectively close two opposite ends of the intermediate rail <NUM> so as to restrain the strip <NUM> inside the intermediate rail <NUM>, and two end caps <NUM> may respectively close two opposite ends of the bottom rail <NUM> so as to retrain the strip <NUM> inside the bottom rail <NUM>.

Referring to <FIG> and <FIG>, each of the bottom rail <NUM> and the intermediate rail <NUM> is independently movable vertically relative to the head rail <NUM> for setting the window shade <NUM> to a desirable configuration. For example, the bottom rail <NUM> may be lowered away from the head rail <NUM> and the intermediate rail <NUM> to expand the shading structure <NUM>, or raised toward the head rail <NUM> and the intermediate rail <NUM> to collapse the shading structure <NUM>. Moreover, the bottom rail <NUM> and the intermediate rail <NUM> may be lowered away from the head rail <NUM> to form a gap for light passage between the head rail <NUM> and the intermediate rail <NUM>. The vertical position of the bottom rail <NUM> and the vertical position of the intermediate rail <NUM> relative to the head rail <NUM> may be controlled with the actuating system <NUM>.

Referring to <FIG> and <FIG>, the actuating system <NUM> is assembled with the head rail <NUM>, and is operable to displace the bottom rail <NUM> and the intermediate rail <NUM> relative to the head rail <NUM> for adjustment. The actuating system <NUM> includes two cord winding assemblies 132A and 132B, an electric motor unit <NUM> and a power supply <NUM>. The cord winding assembly 132A is operable to wind and unwind the two suspension cords <NUM> and <NUM> that are coupled to the bottom rail <NUM> for raising and lowering the bottom rail <NUM>. The cord winding assembly 132B is operable to wind and unwind the other two suspension cords <NUM> and <NUM> that are coupled to the intermediate rail <NUM> for raising and lowering the intermediate rail <NUM>.

The electric motor unit <NUM> is coupled to each of the two cord winding assemblies 132A and 132B, and can be electrically connected with the power supply <NUM>. The electric motor unit <NUM> is operable to independently drive each of the two cord winding assemblies 132A and 132B. For example, the electric motor unit <NUM> may include two motors respectively coupled to the two cord winding assemblies 132A and 132B, each of the two motors being independently operable to drive the corresponding one of the two cord winding assemblies 132A and 132B. The power supply <NUM> can be electrically connected with the electric motor unit <NUM>, and can provide electric power for operating the electric motor unit <NUM>. According to an example of construction, the power supply <NUM> may include a battery casing <NUM> and a power adapter <NUM>. The battery casing <NUM> is adapted to receive one or more battery cells, and can be electrically connected with or disconnected from the electric motor unit <NUM>. The power adapter <NUM> can be plugged to an electric outlet, and can be electrically connected with or disconnected from the electric motor unit <NUM>. The electric motor unit <NUM> can be powered with battery cells of the battery casing <NUM>, or via the power adapter <NUM> connected with an electric outlet.

Referring to <FIG>, the two cord winding assemblies 132A and 132B are respectively disposed at two opposite sides of the electric motor unit <NUM>. In conjunction with <FIG>, <FIG> is a perspective view illustrating a cord winding assembly <NUM> for a window shade, and <FIG> is an exploded view illustrating some construction details of the cord winding assembly <NUM>. Referring to <FIG>, each of the two cord winding assemblies 132A and 132B can have a same construction as the cord winding assembly <NUM> shown in <FIG> and <FIG>. The cord winding assembly <NUM> includes a housing <NUM>, a spool portion <NUM> connected with the suspension cord <NUM>, a spool portion <NUM> connected with the suspension cord <NUM>, and a transmission axle <NUM> rotationally coupled to the two spool portions <NUM> and <NUM>.

The housing <NUM> can include two casing portions 150A and 150B that can be fixedly connected with each other to at least partially define a cavity that is located between two opposite ends 142A and 142B of the housing <NUM> and is adapted to receive the two spool portions <NUM> and <NUM>. The housing <NUM> can include a plurality of mount surfaces <NUM> on which the two spool portions <NUM> and <NUM> can be supported for rotation about a pivot axis <NUM> relative to the housing <NUM>. <FIG> is a perspective view illustrating the two spool portions <NUM> and <NUM> disposed on the mount surfaces <NUM> provided in the casing portion 150A.

According to an example of construction, the two spool portions <NUM> and <NUM> can be provided as two separate parts that can be disposed adjacent to each other inside the housing <NUM>. For example, the spool portion <NUM> can have two axially opposite spool ends 144A and 144B with the spool end 144B having a flange structure 156A, the spool portion <NUM> can have two axially opposite spool ends 146A and 146B with the spool end 146A having a flange structure 156B, and the two spool portions <NUM> and <NUM> can be disposed inside the housing <NUM> with the two flange structures 156A and 156B engaged with each other so that the two spool portions <NUM> and <NUM> are rotationally locked to each other for concurrent rotation about the pivot axis <NUM>. The aforementioned construction may facilitate the assembly of the two spool portions <NUM> and <NUM>. However, it will be appreciated that the two spool portions may also be formed integrally as a single part.

The suspension cord <NUM> can be anchored to the spool portion <NUM> adjacent to the spool end 144B thereof, and the suspension cord <NUM> can be anchored to the spool portion <NUM> adjacent to the spool end 146A thereof. As shown in <FIG>, an outer surface of the spool portion <NUM> can have an opening <NUM> adjacent to the spool end 144B, and the suspension cord <NUM> can be anchored to the spool portion <NUM> by having an end of the suspension cord <NUM> attached through the opening <NUM>. The suspension cord <NUM> can be anchored to the spool portion <NUM> in a similar way. The suspension cord <NUM> may be arranged to extend outside the housing <NUM> at the end 142A thereof, and the suspension cord <NUM> may be arranged to extend outside the housing <NUM> at the opposite end 142B thereof.

The transmission axle <NUM> is rotationally coupled to the two spool portions <NUM> and <NUM> so that the transmission axle <NUM> and the two spool portions <NUM> and <NUM> are rotatable concurrently about the same pivot axis <NUM> relative to the housing <NUM>, the pivot axis <NUM> corresponding to a lengthwise axis of the transmission axle <NUM>. For example, the spool end 144A of the spool portion <NUM> can have a coupling portion <NUM> provided with a square or rectangular hole connected with a hollow interior of the spool portion <NUM>, and the spool end 146B of the spool portion <NUM> can have a coupling portion <NUM> likewise provided with a square or rectangular hole connected with a hollow interior of the spool portion <NUM>. The transmission axle <NUM> can have a cross-sectional shape that matches with that of the holes provided in the coupling portions <NUM> and <NUM>. The transmission axle <NUM> can be disposed through the hollow interior of the spool portion <NUM> and the hollow interior of the spool portion <NUM>, and can be rotationally coupled to the two spool portions <NUM> and <NUM> respectively through the two coupling portions <NUM> and <NUM> thereof. After assembly, the transmission axle <NUM> can extend through the two spool ends 144A and 144B of the spool portion <NUM> and through the two spool ends 146A and 146B of the spool portion <NUM>, and can protrude outside the housing <NUM> at the two opposite ends 142A and 142B thereof. The transmission axle <NUM> and the two spool portions <NUM> and <NUM> can rotate concurrently about the pivot axis <NUM> relative to the housing <NUM> in a first direction for respectively winding the two suspension cords <NUM> and <NUM> around the two spool portions <NUM> and <NUM>, and in a second direction opposite to the first direction for respectively unwinding the two suspension cords <NUM> and <NUM> from the two spool portions <NUM> and <NUM>.

Referring to <FIG> and <FIG>, the cord winding assembly <NUM> can further include two cord guards <NUM> and <NUM> respectively affixed to the housing <NUM> adjacent to the two ends 142A and 142B thereof. The cord guard <NUM> can contact with the suspension cord <NUM> at a location where the suspension cord <NUM> exits the housing <NUM>, and the cord guard <NUM> can contact with the suspension cord <NUM> at a location where the suspension cord <NUM> exits the housing <NUM>. The two cord guards <NUM> and <NUM> can provide protection and facilitate the passage of the two suspension cords <NUM> and <NUM>.

Referring to <FIG>, each of the two cord winding assemblies 132A and 132B can have the same construction as the cord winding assembly <NUM>, and the electric motor unit <NUM> can be respectively coupled to the transmission axle <NUM> of the cord winding assembly 132A and the transmission axle <NUM> of the cord winding assembly 132B at two opposite sides. The electric motor unit <NUM> is thereby operable to drive the transmission axle <NUM> of each of the cord winding assemblies 132A and 132B in rotation for moving the bottom rail <NUM> and the intermediate rail <NUM> as desired. After assembly, one of the two suspension cords <NUM> and <NUM> of the cord winding assembly 132A can extend along the head rail <NUM> past the electric motor unit <NUM> and the cord winding assembly 132B so that the two suspension cords <NUM> and <NUM> of the cord winding assembly 132A can respectively extend at the two opposite sides of the electric motor unit <NUM> for coupling to the bottom rail <NUM>. The two suspension cords <NUM> and <NUM> of the cord winding assembly 132B can be likewise arranged for coupling to the intermediate rail <NUM>.

Although <FIG> and <FIG> illustrate an example having two cord winding assemblies 132A and 132B respectively coupled to the bottom rail <NUM> and the intermediate rail <NUM>, it will be understood that the construction of the cord winding assembly <NUM> is not limited to the illustrated example of application. <FIG> is a perspective view illustrating a variant example of an actuating system not according to the invention I <NUM>. in which the electric motor unit <NUM> may be coupled to one single cord winding assembly <NUM>, which may be coupled to a bottom rail of a window shade having no intermediate rail. Accordingly, the cord winding assembly <NUM> may be suitable for use in various window shades.

<FIG> is a perspective view illustrating a variant construction of a cord winding assembly <NUM> for a window shade, and <FIG> is an exploded view of the cord winding assembly <NUM>. Referring to <FIG> and <FIG>, the cord winding assembly <NUM> can include a housing <NUM>, a spool portion <NUM> connected with the suspension cord <NUM> (shown with phantom lines in <FIG>), a spool portion <NUM> connected with the suspension cord <NUM> (shown with phantom lines in <FIG>), and a transmission axle <NUM> rotationally coupled to the two spool portions <NUM> and <NUM>.

The housing <NUM> can include two casing portions 250A and 250B that can be fixedly connected with each other to at least partially define a cavity that is located between two opposite ends 242A and 242B of the housing <NUM> and is adapted to receive the two spool portions <NUM> and <NUM>.

The spool portion <NUM> can be pivotally connected with the housing <NUM> about a pivot shaft <NUM> so that the spool portion <NUM> is rotatable about a pivot axis 252A relative to the housing <NUM>. The spool portion <NUM> can be pivotally connected with the housing <NUM> about a pivot shaft <NUM> so that the spool portion <NUM> is rotatable about a pivot axis 254A relative to the housing <NUM>, the pivot axes 252A and 254A being parallel and spaced apart from each other. The transmission axle <NUM> is disposed so as to be rotatable relative to the housing <NUM> about a pivot axis 256A that is substantially orthogonal to the pivot axes 252A and 254A, the pivot axis 256A corresponding to a lengthwise axis of the transmission axle <NUM>. For example, the transmission axle <NUM> can have an end connected with a coupling part <NUM> that is assembled with the housing <NUM> for rotation about the pivot axis 256A. The coupling part <NUM> can be disposed adjacent to the end 242A of the housing <NUM>, and can exemplarily have a square or rectangular hole through which the end of the transmission axle <NUM> is engaged for rotationally coupling the transmission axle <NUM> to the coupling part <NUM>. After assembly, the transmission axle <NUM> can extend outside the housing <NUM> at the end 242A thereof. The suspension cord <NUM> connected with the spool portion <NUM> may be arranged to extend outside the housing <NUM> at the end 242A thereof, and the suspension cord <NUM> connected with the spool portion <NUM> may be arranged to extend outside the housing <NUM> at the opposite end 242B thereof.

Referring to <FIG> and <FIG>, the transmission axle <NUM> is rotationally coupled to the two spool portions <NUM> and <NUM> via a gear train <NUM>, which can include a plurality of gears <NUM>, <NUM>, <NUM>, <NUM> and <NUM>. The gear <NUM> is rotationally locked to the spool portion <NUM> so that the gear <NUM> and the spool portion <NUM> are rotatable concurrently about the pivot axis 252A relative to the housing <NUM>. The gear <NUM> is rotationally locked to the spool portion <NUM> so that the gear <NUM> and the spool portion <NUM> are rotatable concurrently about the pivot axis 254A relative to the housing <NUM>. The gear <NUM> is fixedly connected with the coupling part <NUM>, and thereby is rotationally locked to the transmission axle <NUM> so that the gear <NUM> and the transmission axle <NUM> are rotatable concurrently about the pivot axis 256A relative to the housing <NUM>. According to an example of construction, the gear <NUM> can be a bevel gear. The gear <NUM> is pivotally connected with the housing <NUM> about a pivot axis 272A, and is respectively meshed with the gears <NUM> and <NUM>. The gear <NUM> is pivotally connected with the housing <NUM> about a pivot axis 274A, and is respectively meshed with the gears <NUM> and <NUM>. The gear train <NUM> is configured so that the two spool portions <NUM> and <NUM> can be driven by the transmission axle <NUM> to concurrently rotate in one direction (e.g., one of a clockwise direction and an anticlockwise direction) for respectively winding the suspension cords <NUM> and <NUM>, and in another opposite direction (e.g., the other one of the clockwise direction and the anticlockwise direction) for respectively unwinding the suspension cords <NUM> and <NUM>. Accordingly, the transmission axle <NUM> and the two spool portions <NUM> and <NUM> can rotate concurrently relative to the housing <NUM> for respectively winding and unwinding the two suspension cords <NUM> and <NUM>.

Referring to <FIG> and <FIG>, the housing <NUM> can further be provided with a plurality of cord guides <NUM> for guiding the passage of the suspension cords <NUM> and <NUM> through the housing <NUM>. Examples of the cord guides <NUM> may include, without limitation, pulleys.

In conjunction with <FIG> and <FIG>, <FIG> is a perspective view illustrating a window shade <NUM> using two cord winding assemblies 232A and 232B that have the same construction as the cord winding assembly <NUM> described previously. Referring to <FIG>, the actuating system <NUM> is assembled with the head rail <NUM>, and is operable to displace the bottom rail <NUM> and the intermediate rail <NUM> relative to the head rail <NUM>. The actuating system <NUM> shown in <FIG> can be generally similar in construction to the previous embodiment illustrated in <FIG>, except that the two cord winding assemblies 132A and 132B are replaced with the two cord winding assemblies 232A and 232B. Each of the two cord winding assemblies 232A and 232B has the same construction as the cord winding assembly <NUM> described previously with reference to <FIG> and <FIG>, wherein the two suspension cords <NUM> and <NUM> of the cord winding assembly 232A can be coupled to the bottom rail <NUM> and the two suspension cords <NUM> and <NUM> of the cord winding assembly 232B can be coupled to the intermediate rail <NUM>. The electric motor unit <NUM> is carbo respectively coupled to the transmission axle <NUM> of the cord winding assembly 232A and the transmission axle <NUM> of the cord winding assembly 232B at two opposite sides. The electric motor unit <NUM> is thereby operable to drive the transmission axle <NUM> of each of the cord winding assemblies 232A and 232B in rotation for moving the bottom rail <NUM> and the intermediate rail <NUM> as desired.

Claim 1:
An actuating system (<NUM>) for a window shade (<NUM>), comprising an electric motor unit (<NUM>) and two cord winding assemblies (<NUM>, 132A, 132B, <NUM>, 232A, 232B);
wherein each of the two cord winding assemblies (<NUM>, 132A, 132B, <NUM>, 232A, 232B) comprises:
a housing (<NUM>, <NUM>) having a first and a second end (142A, 242A, 142B, 242B) opposite to each other, and a cavity between the first and second ends (142A, 242A, 142B, 242B);
a first spool portion (<NUM>, <NUM>) connected with a first suspension cord (<NUM>), and a second spool portion (<NUM>, <NUM>) connected with a second suspension cord (<NUM>), the first and second spool portions (<NUM>, <NUM>, <NUM>, <NUM>) being disposed in the cavity of the housing (<NUM>, <NUM>); and
a transmission axle (<NUM>, <NUM>) rotationally coupled to the first and second spool portions (<NUM>, <NUM>, <NUM>, <NUM>) and extending outside the housing (<NUM>, <NUM>) at least at the first end (142A, 242A) thereof, the transmission axle (<NUM>, <NUM>) and the first and second spool portions (<NUM>, <NUM>, <NUM>, <NUM>) being rotatable concurrently relative to the housing (<NUM>, <NUM>) in a first direction for respectively winding the first and second suspension cords (<NUM>, <NUM>) around the first and second spool portions (<NUM>, <NUM>, <NUM>, <NUM>), and in a second direction opposite to the first direction for respectively unwinding the first and second suspension cords (<NUM>, <NUM>) from the first and second spool portions (<NUM>, <NUM>, <NUM>, <NUM>); and
wherein the two cord winding assemblies (<NUM>, 132A, 132B, <NUM>, 232A, 232B) are respectively disposed at two opposite sides of the electric motor unit (<NUM>), the electric motor unit (<NUM>) being respectively coupled to the transmission axle (<NUM>, <NUM>) of each of the two cord winding assemblies (<NUM>, 132A, 132B, <NUM>, 232A, 232B).