GB1046268A - Electrically operated venetian blinds - Google Patents

Abstract

1,046,268. Venetian blinds. J. AVERY & CO. (EST. 1834) Ltd. Oct. 16, 1964 [July 23, 1963; Sept. 27, 1963], Nos. 29049/63 and 38111/63. Heading E1J. In a venetian blind raised, lowered and tilted by a reversible electrical motor 17 driving directly cord drums 13 to raise or lower the slats and a driven wheel 25 in permanent engagement with a pinion 24 on the driving shaft 11, the driven wheel 25 is clutched to the tilt shaft 12 by means of two torsion spring type clutches one or the other of which is effective to raise or lower the blind according to direction of initial movement of the motor rendering the appropriate clutch operative to couple the tilt shaft to the wheel 25. The wheel 25 integral with lateral sleeve 251, 252 (Fig. 3, not shown) is freely rotatable on tilt shaft 12 and the sleeves 251, 252 are aligned with sleeves 261 secured to the shaft 12 and having thereon a settable tilt cam 30 which screens the teeth 281 on further sleeves 28 rotatable over the sleeves 251, 252, 261 with torsion springs 271, 272 Fig. 3 (not shown) sandwiched therebetween with an interference fit on the sleeves 251, 261 and 252, 261, one end 273 of each spring being fixed to the ratchet sleeve 28, and the other end left in frictional contact with the sleeve 261. When the motor is rotated (in the forward direction) to raise or lower the blind and in the absence of tilt control the initial movement of shaft 11 loosens the torsion springs and allows wheel 25 to rotate freely on the tilt shaft 12. In the lowered and closed condition of the blind, the cam 30 is so set to release the associated pawl 29 to engage the teeth 281 of the sleeve 28 and to exert pressure on the end 273 of the enclosed spring to cause this spring to resist further winding which then opens to disconnect the drive of the wheel 25 from the tilt shaft.