The quick release device may comprise a shade tube, a gear wheel engaging with the shade tube, a pawl removably engaging with the gear wheel and a solenoid configured to activate the pawl. The activation of the pawl disengages the pawl from the pawl wheel and allows the shade tube to rotate. The quick release device may also include a shade tube, a rotating brake plate engaging with the shade tube, a spring configured to apply pressure to the rotating brake plate and a magnet configured to apply magnetism to the spring. In response to the magnet applying magnetism to the spring, the spring contracts and releases pressure on the rotating brake plate and allows the shade tube to rotate.

A displacement controlling device comprises a shaft having a displacement region, a movable unit connected to the shaft and configured to move within the displacement region, a damper connected to one end of the shaft, and a restraint unit arranged between the movable unit and the damper, wherein the restraint unit is configured to be driven by the movable unit from a first position toward a second position; the damper outputs a resistance when the restraint unit is at the first position, and the damper stops outputting the resistance if the restraint unit is at the second position.

A window covering is provided according to the present application, to achieve automatic extending or retracting of a window covering curtain. The window covering includes: a rotating shaft for extending and retracting control, a wound sheet spring and a cord winding box. The extending and retracting of the window covering curtain is achieved by winding the curtain pull cord via the cord winding box, and the force transmission between the wound sheet spring and the cord winding box is achieved by gear transmission. A spring wound sheet is provided inside the wound sheet spring. One proper wound sheet spring is chosen according to the weight of the window covering curtain to allow the window covering curtain to maintain a balance state of force without under the effect of an external force, to fix the extending or retracting state of the window covering curtain.

A chain assembly includes a wheel secured on a shaft. A chain manually rotates the wheel and the shaft. A one way bearing has an inner race secured to the shaft and has an outer race that can freely rotate in only one direction in relation to the inner race. A brake drum is coupled to the outer race. Brake shoes are in operative contact with the brake drum to apply friction to the brake drum when there is relative motion between them. A brake adjuster adjusts the braking force applied by the brake shoes on said brake drum. The one way bearing is arranged to maintain the brake drum stationary in one direction of rotation of the shaft and rotate the brake drum in the opposite direction of rotation resulting in a degree of braking of the shaft as determined by the brake adjuster.

The invention relates to an operating mechanism for a cordless window covering such as a roller blind, comprising at least one substantially stationary inner shaft which is connectable to the fixed world and at least one axially rotatable drive shaft configured for driving and thereby lowering and/or raising the window covering. The system is in particular configured to provide controlled operation of a cordless window covering.

A window shade system may comprise a drive hub having a dampener comprised of dampening material, wherein the drive hub engages with at least one of a shade tube or a brake hub. The dampener may include one or more tabs that engage the brake hub. The dampener may be configured to dampen the torque from a spinning of the shade tube. The dampener may be comprised of urethane. The dampener may be incorporated onto an outside surface of the drive hub. The dampener may be located within the drive hub. The drive hub may be in the form of a cap that fits over the dampener. The drive hub may include rounded corners. The dampener may be configured in the form of one or more cylindrical rods.

A compound spring bar includes a compound spring having one end fixed and the other end rotating as a curtain fabric opens and closes, where the compound spring includes at least two springs with different diameters, the springs are nested in layers according to their diameters, adjacent springs are connected in series, and all the springs form a combined spring; and free ends of an innermost spring and an outermost spring in the combined spring, which are not connected to other springs in series, are two ends of the combined spring. The

A fenestration assembly includes a sash, a frame surrounding the sash, and at least one screen assembly mounted in at least one of: the top portion and the bottom portion. The frame includes a top portion, a bottom portion, and two jambs forming first slots extending lengthwise along at least a portion of the jamb. The first slots each include a screen edge retention feature. The screen assembly includes a roller assembly substantially hidden from view, a screen material attached to the roller assembly, and a plurality of raised features. Edges of the screen material extend into the first slots. The raised features are attached to each of the edges of the screen material. The raised features are configured to engage the screen edge retention features and retain each of the edges of the screen material at least partially within the first slot of each of the two jambs.

A window shade system may comprise a drive hub having a dampener comprised of dampening material, wherein the drive hub engages with at least one of a shade tube or a brake hub. The dampener may include one or more tabs that engage the brake hub. The dampener may be configured to dampen the torque from a spinning of the shade tube. The dampener may be comprised of urethane. The dampener may be incorporated onto an outside surface of the drive hub. The dampener may be located within the drive hub. The drive hub may be in the form of a cap that fits over the dampener. The drive hub may include rounded corners. The dampener may be configured in the form of one or more cylindrical rods.

A door operator with high-speed operation and fire escape functions comprises a motor, a high-speed centrifugal brake module, a centrifugal reduction module, a central shaft locking module and a first and second clutch module. In the stationary state, the high-speed centrifugal brake module, centrifugal reduction module and central shaft locking module are connected to each other, and the drive shaft of the motor is locked by the central shaft locking module. In the normal operation, the first clutch module disengages the high-speed centrifugal brake module from the centrifugal reduction module, and the drive shaft is rotatable at high speed. In the event of fire escape, the second clutch module disengages centrifugal reduction module from central shaft locking module, and the drive shaft rotates at a lower speed. The device will provide high-speed rotation under normal operation, and automatically close the door panel at a gradually lowered speed in the event of fire escape.