In one aspect, a covering for an architectural structure includes a headrail, a bottom rail supported relative to the headrail, and at least one stackable covering element positioned between the headrail and the bottom rail. The covering also includes an overpowered lift system configured to provide a lifting force that raises the bottom rail relative to the headrail towards a retracted position of the covering. In addition, the covering includes retention structure provided in operative association with the bottom rail, with the retention structure being configured to engage at least one hold-down bracket to hold the bottom rail in position relative to the headrail against the lifting force provided by the overpowered lift system.

A window covering includes a fixed rail, a covering material, a lifting cord and a winding mechanism, wherein the covering material is positioned under the fixed rail, and the winding mechanism includes a reel, a rotating member and a stopper. The reel is adapted to wind up or release the lifting cord, in order to drive the covering material to move toward the fixed rail to fold, or to move away from the fixed rail to unfold. The rotating member passes through the reel. The stopper is operably pivoted relative to the rotating member. When the rotating member rotates independently from the reel, the stopper is driven to pivot, and is protruded from a surface of the rotating member, and the stopper would abut against a block of the fixed rail to stop the rotation of the rotating member. Therefore, when a covering material of the window covering is unfolded and meets an obstacle, the covering material could stop unfolding automatically.

A window covering includes a fixed rail, a covering material, a lifting cord and a winding mechanism, wherein the covering material is positioned under the fixed rail, and the winding mechanism includes a reel, a rotating member and a stopper. The reel is adapted to wind up or release the lifting cord, in order to drive the covering material to move toward the fixed rail to fold, or to move away from the fixed rail to unfold. The rotating member passes through the reel. The stopper is operably pivoted relative to the rotating member. When the rotating member rotates independently from the reel, the stopper is driven to pivot, and is protruded from a surface of the rotating member, and the stopper would abut against a block of the fixed rail to stop the rotation of the rotating member. Therefore, when a covering material of the window covering is unfolded and meets an obstacle, the covering material could stop unfolding automatically.

Venetian blinds to cover a window having a window frame and a window pane, the venetian blinds including a plurality of panels interconnected with each other, a cord to pivot the plurality of panels in a first pivoting direction to allow sunlight to be visible through the plurality of panels, and a second pivoting direction to prevent the sunlight from being visible through the plurality of panels, and a plurality of suction cups disposed on surfaces of the plurality of panels facing the window.

A spring drive system for a window shade includes a housing, a plurality of rotary members, a spring and a latch. The rotary members are rotationally linked to one another and pivotally connected with the housing, wherein the rotary members include a rotary drum that is connected with a suspension member and is rotatable relative to the housing for winding or unwinding the suspension member. The spring is assembled with the housing, and can bias the rotary drum in rotation for winding the suspension member. The latch is assembled with the housing, the latch being movable to engage with and disengage from one of the rotary members to respectively prevent and allow rotation of the rotary drum.

A spring drive system for a window shade includes a housing, a plurality of rotary members, a spring and a latch. The rotary members are rotationally linked to one another and pivotally connected with the housing, wherein the rotary members include a rotary drum that is connected with a suspension member and is rotatable relative to the housing for winding or unwinding the suspension member. The spring is assembled with the housing, and can bias the rotary drum in rotation for winding the suspension member. The latch is assembled with the housing, the latch being movable to engage with and disengage from one of the rotary members to respectively prevent and allow rotation of the rotary drum.

The invention relates to a screen, comprising a first control unit (610) comprising a first drive shaft (612) and at least one first cord spool (630) rotatable with the first drive shaft for winding and unwinding a first lift cord (634) extending between a head rail and a middle rail; a second control unit (620) comprising a second drive shaft (622), and at least one second cord spool (632) rotatable with the second drive shaft for winding and unwinding a second lift cord (636) extending between the head rail and the bottom rail; and a shaft rotation limiting system (100) comprising a threaded shaft arranged on and rotatable in unison with one of the first and the second drive shafts, a coupling element threaded on said threaded shaft, wherein the coupling element is associated with and rotatable in unison with the other drive shaft.

The invention relates to a screen, comprising a first control unit (610) comprising a first drive shaft (612) and at least one first cord spool (630) rotatable with the first drive shaft for winding and unwinding a first lift cord (634) extending between a head rail and a middle rail; a second control unit (620) comprising a second drive shaft (622), and at least one second cord spool (632) rotatable with the second drive shaft for winding and unwinding a second lift cord (636) extending between the head rail and the bottom rail; and a shaft rotation limiting system (100) comprising a threaded shaft arranged on and rotatable in unison with one of the first and the second drive shafts, a coupling element threaded on said threaded shaft, wherein the coupling element is associated with and rotatable in unison with the other drive shaft.

A headrail for a motorized window covering is described that includes a motor and a gearbox coupled to the motor that is configured to actuate a window covering. The headrail includes a safety detector with one or more sensors that detect an irregular strain when the window covering is being raised. The headrail may further comprise a recoil mechanism or a deactivation mechanism to reduce the likelihood of damage to the window coverings and/or individuals caught or tangled in the window covering.

A covering for an architectural opening has a horizontal movable rail supported by cords, with a variety of configurations which allow the movable rail to be moved up and down while concealing the cords.