| 摘要 |
1,187,214. Venetian blinds. HUNTER DOUGLAS INTERNATIONAL Ltd. 17 July, 1967 [15 July, 1966], No. 32776/67. Heading E1J. In a venetian blind comprising a slat lifting, lowering and tilting mechanism operated by a single hexagonal shaft 3 the ladder tapes 10, 11 are attached at each end to the ends 8, 9 of a helical spring 7 wound on an axial cylindrical portion 6 of a winding drum (5) on the shaft 3 for the lift straps 4, the weight of the ladders and their slats causing the helical spring to tighten on the portion 6 so as to turn with the shaft 3 until the end 8, or 9 of the spring encounters a fixed stop 13 or 14 on the supporting frame 1 whereupon the spring is slackened and the portion 6 slides past on continued rotation of the shaft in the lifting or lowering operation of the blind. The stops 14 may be removable to different positions, e.g. in the form of a peg in one of a series of holes (Figs. 3 and 4) and spring clutches may be provided on portions 6 on both sides of the lifting and lowering drum (5) the corresponding spring ends being connected by linear or U-shaped bars which support the ladder tape. |
