Automatic lock for roller blind - has pin-joined curved strap to secure head of blind to roller and to stop upward movement of deployed blind

摘要

The automatic stop secures a roller blind in the fully lowered position, using an articulated segmental link (3) between the head (H) of the blind (11) and the winding drum (1). The link houses onto the drum when the blind is retracted, having a span (5) which equals the horizontal offset of the major deployed blind (12) plane relative to the drum. When the blind is fully lowered, continued drum rotation causes the link to move into a horizontal cantilevered position applying some downward vertical pressure to the blind. A face (2a) on the drum now stops further upward pivoting of link and prevents upward blind movement in the absence of drum rotation. The link may be fixed in the drum groove (2) by winged 'U' straps (5) over stub axles (4).