Roller blind with cord operated winding mechanism - has spring loaded brake to prevent unwanted unrolling

摘要

The blind (1) has a fabric sheet (3) rolled around a hollow roller (2). At one end, the roller fits over the end shaft (4) of a winding unit (5). The shaft is secured to a ribbed roller (9) inside the winding unit casing (6). The loop of control cord (11) for the blind has small balls at intervals, the spacing being equal to that between the ribs on the winding roller. Pulling on either side of the loop therefore rotates the roller and raises or lowers the blind. In the casing, below the ribbed roller, is a similar ribbed roller, the rotation shaft of which is supported in slots by a U-shaped spring (19). The action of the second or brake roller and 'pinch' protrusions (23,24) on the inside of the casing, ensures that the cord, and hence the blind, will only move when the cord is being pulled from below.