GB1227619A - - Google Patents

Abstract

1,227,619. Roller blinds. GRIESSER. 27 Nov., 1968 [1 Dec., 1967; 19 April, 1968], No. 56263/68. Heading A4B. A roller blind assembly includes a blind formed by two adjacent screens 14, 15 provided at their spaced apart lower edges with respective weighting blades 6, 7, each screen 14, 15 being formed of horizontal strips which are alternately of open work or light-transmitting material and opaque, laterally disposed guides for at least one of the screens 14, 15, and winding means at the top of the blind including a drum 11 on which the screens may be wound. together, means being provided whereby operation of the winding means from the fully unrolled position of the blind first raises one of the screens 14 and after a predetermined delay raises the other 15 of the screens; This relative displacement of the screens is adjustable to control the quantity of air or light passing through the blind. In one embodiment, Fig. 1, one screen 15 is secured by strips 16, 17 and a screw 18 slidable under gravity in circumferential slots 19 in the drum 11 as the latter rotates in the initial period of rolling up of the blind. In another embodiment, Fig. 3, one screen 27 is suspended from a rod 28 anchored to rings 29 loosely mounted on the drum 21 and the other screen 26 is carried by a rod 25 on a flexible strip 24 disposed between the drum 21 and the rings 29, the strip 24 being anchored by a strip 22. The screen 27 remains stationary until its rod 28 is engaged by the rod 25 at the end of the initial period of rolling up of the blind. In a further embodiment, Fig. 5, one screen 35 is carried by tapes 36 passing through drum slots 37 and wound on pulleys 38 rigid with the drum drive shaft 39. A boss 40 rigid with the shaft 39 is engageable with the drum stops 41 to rotate the drum 31 after an initial period of rotation of the shaft 39. In a further embodiment, Fig. 7, a bead 61 on one screen 53 is held in a U-shaped support 62 at the top of a side guide 59 so that the other screen 54 can move relative to the first screen 53 in the final stage of lowering the blind.