SCROLLING UNIT FOR ELECTRIC WINDOW CURTAIN

A window curtain includes a top rail, a bottom rail and a curtain between the top and bottom rails. A transmission unit and a scrolling unit are received in the bottom rail. Transmission unit includes a control member, a motor, and a shaft connected to the motor. The scrolling unit includes a case in which a passive part, a first prat and a second part are accommodated. The shaft of the motor drives the scrolling unit. A first rope is connected to the first part. A second rope is connected to the second part. The first and second ropes pass through the curtain and are connected to the top rail via the first and second transition members. The transmission unit and the scrolling unit are received in the bottom rail to reduce the weight of the top rail, and are easily maintained.

BACKGROUND OF THE INVENTION

1. Fields of the Invention

The present invention relates to an electric window curtain, and more particularly, to a scrolling unit of an electric window curtain.

2. Descriptions of Related Art

Electric window curtains have become very popular in recent years. Not only are there no ropes to prevent accidents, but also the curtains can be opened or closed through electronic control.

Most of the transmission devices of electric window curtains are installed in the top rail of the electric curtain. However, there could be no room for assembly of the top rail that may occupies a certain room because the transmission device received in the top rail. In addition, the transmission device in the top rail, it requires equipment to support the parts when installing, and this may cause inconvenience maintenance in the feature.

Most of the electric window curtains use a motor to drive the shaft to operate the ropes. When the curtain is blocked by objects, it causes uneven release of the rope, which may further cause the ropes to be entangled and knotted.

The present invention intends to provide a scrolling unit of an electric window curtain to ensure that the curtain is smoothly operated and to eliminate the shortcomings mentioned above.

SUMMARY OF THE INVENTION

The present invention relates to a window curtain and comprises a top rail, a bottom rail, a curtain connected between the top rail and the bottom rail, a transmission unit and a scrolling unit. The transmission unit and the scrolling unit are both located in the bottom rail. The transmission unit includes a control member, a motor and a shaft connected to the motor. The control member controls operation of the motor. The scrolling unit includes a case in which a passive part, a first prat and a second part are accommodated. The passive part includes a bevel gear and a spur gear which is co-rotated with the bevel gear. The shaft extends into the case and is connected to a driving gear which is engaged with the bevel gear. The first part includes at least one first gear, a first spool and a first rope. The at least one first gear is engaged with the spur gear. The first rope is wrapped to the first spool. An end of the first rope passes through a first transition member and the curtain, and is fixed to the first end of the top rail. The second part includes at least one second gear, a second spool and a second rope. The at least one second gear is engaged with the at least one first gear. The second rope is wrapped to the second spool. An end of the second rope passes through a second transition member and the curtain, and is fixed to the second end of the top rail.

The first transition member and the second transition member are respectively located to two ends of the bottom rail. The first transition member and the second transition member have identical structure and located symmetrically to each other. Each of the first transition member and the second transition member includes a first rod and a second rod, wherein the first rod is perpendicular to the bottom rail, and the second rod is parallel to the bottom rail. The first/second rope are wrapped to the first rod and turn 90 degrees to be wrapped to the second rod. The first/second rope then passes through the curtain and is fixed to the top rail.

Preferably, the transmission unit includes a power supply which is electrically connected to the motor.

Preferably, the power supply includes a box and a rechargeable battery is received in the box.

Preferably, the control member of the transmission unit is controlled by a wireless remote controller so as to activate the motor.

Preferably, the bottom rail includes a bottom pate and a housing. The bottom plate is connected to the housing to form a room between the housing and the bottom plate. The transmission unit, the scrolling unit, the first transition member, the second transition member are located in the room between of the housing and the bottom plate.

The advantages of the present invention are that the transmission unit, the scrolling unit, the first transition member and the second transition member are located in the bottom rail so that the weight of the top rail is reduced. The transmission unit and the scrolling unit are easily maintained.

The electric window curtain can be operated by the battery even when an electric power outage happens.

The transmission unit is located in the bottom rail, so that the replacement of the battery is easy and convenient.

The scrolling unit is transversely installed so that the ropes are not likely entangled with each other.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring toFIGS. 1 to 8, the electric window curtain of the present invention comprises a top rail1, a bottom rail2, a curtain3connected between the top rail1and the bottom rail2, a transmission unit4, a scrolling unit5, a first transition member6and a second transition member7.

The top rail1includes a U-shaped cross section and connected to the top edge of a window. The transmission unit4, the scrolling unit5, the first transition member6and the second transition member7are received in the bottom rail2so that the top rail1is easily installed. The transmission unit4and the scrolling unit5lift or lower the curtain3.

As shown inFIGS. 1 and 2, the bottom rail2includes a bottom plate21and a housing22. The bottom pate21is connected to the housing22to form a room between the housing22and the bottom plate21. The transmission unit4, the scrolling unit5, the first transition member6and the second transition member7are located in the room between of the housing22and the bottom plate21.

The curtain3can be a comb-shaped curtain in this embodiment, other types of curtains can also be used, such as blinds or Roman shade.

As shown inFIGS. 2, 7 and 8, the transmission unit4includes a control member41, a motor42and a shaft43. The shaft43is connected to the motor42. The control member41controls operation of the motor42, such as number of revolutions and rotational directions. The shaft43of the motor42is connected to the scrolling unit5. The transmission unit4includes a power supply44which is electrically connected to the motor42. The power supply44includes a box442and a rechargeable battery441is received in the box442. A cover443is connected to the box42to accommodate the re rechargeable battery441in the box442. When an electric power outage happens, the curtain3can also be operated by the power from the rechargeable battery441.

As shown inFIGS. 2 to 6, the scrolling unit5located in the bottom rail2and includes a case51in which a passive part52, a first prat53and a second part54are accommodated. The passive part52includes a bevel gear521and a spur gear522which is co-rotated with the bevel gear521. The shaft43extends into the case51and is connected to a driving gear431. The driving gear431is engaged with the bevel gear521, and the spur gear522is located beneath the bevel gear521.

The first part53including at least one first gear531, a first spool532and a first rope533. The at least one first gear531is engaged with the spur gear522. One of two ends of the first rope533is wrapped to the first spool532, the other one of the two ends of the first rope522passes through the first transition member6and the curtain3, and is fixed to the first end of the top rail1.

The second part54includes at least one second gear541, a second spool542and a second rope543. The at least one second gear541is engaged with the at least one first gear531. One of two ends of the second rope543is wrapped to the second spool542, and the other one of the two ends of the second rope542passes through the second transition member7and the curtain3, and is fixed to the second end of the top rail1.

As shown inFIGS. 1 and 2, the first transition member6and the second transition member7are respectively located to two ends of the bottom rail2. The first transition member6and the second transition member7have identical structure and are located symmetrically to each other. Each of the first transition member6and the second transition member7includes a first rod61/71and a second rod62/72. The first rod61/71is perpendicular to the bottom rail2. The second rod62/72is parallel to the bottom rail2. The first/second rope533/543is wrapped to the first rod61/71and turns 90 degrees to be wrapped to the second rod62/72, and the first/second rope533/543passes through the curtain3and is fixed to the top rail1.

The top rail1is light and easily to be installed because the transmission unit4, the scrolling unit5, the first transition member6and the second transition member7are located in the bottom rail2. In addition, the transmission unit4and the scrolling unit5are easily maintained in the bottom rail2.

The curtain3can also be operated by the power from the rechargeable battery441when an electric power outage happens.

The control member41of the transmission unit4is controlled by a wireless remote controller (not shown) so as to activate the motor42.

When in use, the shaft43drives the passive gear52of the scrolling unit5, and the first part53and the second part54are co-rotated to scroll or release the first and second ropes533,543to lift or lower the curtain3. Besides, the scrolling unit5is transversely installed so that the first and second ropes533,543are not likely entangled with other.