GB428164A - Venetian blind construction - Google Patents

Abstract

428,164. Venetian blinds. KUYPER, P. H., 105, Main Street, Pella, Iowa, U.S.A. May 2, 1934, No. 13266. [Class 52 (v)] The head bar of a venetian blind comprises a hollow casing B through the bottom wall 14 of which pass straps 42, 44 forming extensions of the ladder tapes 54, means being provided within the casing for winding and unwinding the straps to alter the tilt of the blind slats. The straps are wound on shafts 20, 22 rotated in opposite directions by gear wheels 28, 30 turned by a drum 32 on which is wound a cord 34 passing out of the casing over a roller 37. A brake comprising a spring strip 38 engages the shafts 20, 22 to retain the slats 55 in adjusted position. The straps 42, 44 are doubled and connected with the looped upper ends of the ladder tapes 54 by fasteners 46 while their other ends are secured in V-shaped slots 48 in the shafts 20, 22. When the slats are closed, Fig. 11, they are supported solely by the right-hand strap 42 and closely overlapped in a position near the window frame. The lowermost slat of the blind is made of metal so that its weight keeps the blind taut. The lifting ropes 60 extend over pulleys 62 in the casing to a frictional locking means 68 with guide pulleys and a locking lever 74 operated by a cord to force the ropes 60 against grooves formed in a bracket 68. On pulling the ropes 60 the lever 74 is released. The casing B is supported between brackets A secured to the window frame and comprising webs 84 with front and rear flanges 90, 88 and a bottom flange 86 upon which the casing rests. Spring latches 92 fixed to the inside of the rear wall 16 of the casing snap behind the front flanges 90 and take up small differences between the length of the casing and the width of the window. The brackets may be made of different widths to compensate for large differences. The straps 42, 44 may be wound in opposite directions on a single drum secured to a shaft in the casing or a strap 44a, Fig. 16, secured at its ends to the tapes 54<a> may pass over the drum 23 and be secured to it by a tack 45. When two straps are wound in a single drum they are of half the width of the drum and offset axially. The drum 32 may be replaced by bevel gears operated by a pulley outside the casing.