Patent GB-704422-A (GB)
Title: Improvements relating to venetian blinds
Inventor: ORCHARD-LISLE ULRIC LOCK
IPC: E06B9/305
Filed: 1952-01-08
Abstract: 704,422. Venetian blinds. LISLE, U. L. ORCHARD-, and GIRLING, A. H. G. Jan. 7, 1953 [Jan. 8, 1952 ; Nov. 8, 1952], Nos. 538/52 and 28192/52. Class 20 (3) A venetian blind of the type wherein the upper tilting lath 16 of a lath assembly, adjustable by a cord 21, is suspended from a head rail 10 is characterized in that the tilting lath 16 when not being adjusted has one end member resting on a fixed supporting surface 123, the weight of the lath assembly imposing a frictional resistance between said member and the surface 123 so that the lath 16 tends to remain in its adjusted position. The tilting lath, made e.g. of wood, carries pins 18, 17 at its ends for pivotal mounting in elongated slots 124, 132, formed respectively in supporting brackets 12, 13, secured by screws to the ends of the head rail 10. A pulley wheel 19, for the cord 21, comprises two juxtaposed discs 191, 192, the inner disc 192 having a flanged periphery 194 and the outer disc 191 having a pressed out tongue 193 adapted to pass through a corresponding slot 195 in the disc 192 for fixing by screws 20 to the adjacent end of the tilting lath 16. In this manner the two discs are clamped together to form a peripheral groove to accommodate the cord 21, the lower peripheral portion of the pulley normally resting on the flange 123 of the bracket 12. The cord 21 passes over rollers 22 and has its free ends passed through holes in the flanged portion 194 of the pulley 19 and anchored thereto by knotting. The tilting lath 16, in the case of a long blind, is supported at intermediate positions by webbing slings 23, the ends of which are secured to The head rail. On adjusting the tilting lath, by pulling the relevant run of the cord 21, there is a tendency to lift the pulley 19 off the flange 123, the pivot pins 18, 17, being correspondingly raised in their respective slots 124, 132, so that the resistance to turning is reduced and the tilting of the laths is facilitated. In a modification, Figs. 8, 9, the tilting lath 16 is provided, at the end adjacent the tilting cord 21, with a pivot pin 18 which is adapted to rest on the bottom of a slot 125 in a support bracket 12, the opposite pivot pin 17 being located at the bottom of a slot 135 in a support bracket 13. The ends of the cord 21 are anchored to the corners of the tilting lath 16 adjacent the pivot pin 18. A semi-circular disc 24, fixed to the end of the lath 16 adjacent to the pivot pin 17, normally rests on an inwardly turned flange 136 on the bracket 13, but operating the cord 21 tends to lift the cam 24 off the flange 136, so that the laths can be more easily adjusted. The pulley 19, Fig. 3, may be provided with V-shaped notches adapted to coact with a projection on the flange 123 when the laths are in their "fully open" and " fully closed positions to ensure positive holding of the laths in these positions. In an alternative construction the V-shaped notches in the pulley are replaced by arcuate recesses which are adapted to provide seatings for a roller mounted at the bottom of the bracket 12.