WO2005095748A1

WO2005095748A1 - System for working vertically-operated blinds by means of a reducing mechanism combined with a multiplying mechanism

Info

Publication number: WO2005095748A1
Application number: PCT/IT2004/000202
Authority: WO
Inventors: Vito Vigilante
Original assignee: Ctv Automatismi Vigilante S.R.L.
Priority date: 2004-03-30
Filing date: 2004-04-13
Publication date: 2005-10-13
Also published as: ITMI20040618A1

Abstract

System for working a vertically-operated blind by means of a reducing mechanism combined with multiplying mechanism placed between a handle and the cords of the blind.

Description

System for working vertically-operated blinds by means of a reducing mechanism combined with a multiplying mechanism

The invention concerns systems for operating vertically-moving blinds of various types, Venetian, pleated, as well as others

This is generally done by attaching one or more cords to a base plate, the cords then passing up through the slats to a fixed box from where, by means of devices made for the purpose, they are joined to a chain hanging from the box and fitted with a handle. On pulling the handle, the slats are raised to bring the blind to its closed position. On releasing the handle the slats fall by gravity and the blind assumes its operative fully extended position. In view of the height of window space, use of the handle often raises problems of installation and operation. It is often necessary to install, close to the blind, a sort of hook to fix the length of the chain when the blind is being lowered, especially bearing in mind that the blind often extends down to the floor, while working it is done approximately at the height of a person. This leads to some imbalance between the optimum travel of the chain, worked by the user, and the cords that pull the base slat of the blind up towards the fixed box when the blind is being raised.

The above invention solves this problem ensuring efficient functioning of the blind and far less effort on the part of the user. Subject of the invention is a system for working vertically-moving blinds, comprising a motion reducing mechanism combined with a multiplying mechanism.

The multiplying mechanism is created by joining the blind to an upper fixed box with two or more cords each of which, starting from the thick slat at the base of the blind, winds around a pair of pulleys freely turning on two crosswise shafts respectively supported by a first headpiece, fitted at one end of the box, and by a carriage translating inside said box. The multiplying mechanism makes possible values of multiplication corresponding to the number of the pairs of pulleys, respectively supported by the first fixed headpiece and by the carriage, the cords starting from the base slat being wound around said pulleys. There are two or more cords according to the width of the blind. The reducing mechanism is created'by joining the carriage to a chain a first branch of which, departing from a second headpiece on the second end of the box, winds round a horizontal pulley, freely rotating inside the carriage; a second branch of the chain, substantially parallel to the first, emerges from the carriage and, returning to said second headpiece, leaves it in a downward direction from where it is pulled to work the blind.

A series of little balls are placed at regular intervals along the chain. In one type of execution the second headpiece presents a central passage in which lies the second branch of the chain, said passage being connected to a first and a second crosswise channel, extending respectively to one side and to the other of said headpiece, allowing the chain to emerge and therefore be moved to the right or left of the blind as required. The end of the chain leaving the second headpiece of the box is joined to a handle for convenient operation by the user.

The crosswise channels connecting with the central passageway in the second headpiece, terminate in a slot wider than the chain but narrower than the diameter of the balls so that, on pulling chain slightly off vertical, it slides freely and the blind is raised or lowered as required while, if used vertically, ,one of the little balls will be held back at the bottom of the slot so fixing the blind at the desired height. In another type of execution the two branches of the chain both pass along the central passage in the second headpiece, one branch leaving from the open end of the first crosswise channel and the other branch from the open end of the second crosswise channel. The sides of an upright, placed at the openings of said crosswise channels, carry a first and a second anchoring device consisting of a narrow slot through which the chain itself can pass but not the balls. In this way the first banch of the chain can be held by a first anchoring device and the blind be worked using the second branch of the chain, also fitted with a handle, and the blind be fixed at the desired height inserting said second branch of the chain inside the narrow slot in the second anchoring .device.

The blind can therefore be worked both from inside and outside the house. The invention offers evident advantages. Reduction of the stroke made by the carriage that raises the blind, in relation to the pull on the chain made by the handle, ensures smooth and gradual movement to the great benefit of the user. The longer movement made by the blind cords compared with that made by the chain, at very high ratios chosen according to preference and to the length and type of blind, make it extremely quick and easy to raise or lower the blind.

The problems of what to do with the chain when the blind is fully extended are avoided even if it is a very long one. Characteristics and purposes of the invention will be made still clearer by the following examples of its execution illustrated by diagrammatically drawn figures. Fig. 1 Venetian blind showing the method of working it, subject of the invention, perspective.

Fig. 2 The blind, partially cut away and partly exploded, perspective with enlarged detail. Fig. 3 A diagrammatic view of the blind.

Fig. 4 A version of the blind with double manual control, perspective.

The Venetian blind 10 comprises the slats 20 hung, by means of two cords 24 and 26 passing through holes 22 in the slats, to the upper box 30. Said box 30 is divided by longitudinal projections 32 into an upper channel 34 and a lower channel 36.

A plate-shaped part 40 is inserted in the lower channel 36.

At one end of the upper channel 34 is the first headpiece 50 for the set of transmission pulleys 60. Said first headpiece 50 carries a comb-like structure 52 with teeth 54.

The teeth of the comb each present a slot 56 to support the crosswise shaft 58 and set 60 of six pulleys 62-67 able to turn freely, between one tooth and another, around said shaft 58.

Rearward of the comb-like structure 52 is a bracket 70 containing six holes 72-77 one for each of the pulleys 62-67.

Freely sliding inside the upper channel 34 of the box 30 is a carriage

90 that, towards the first headpiece 50, presents a comb-like structure 92 substantially similar to the structure 52 fixed to the headpiece 50. Each tooth presents a slot 96 to carry the shaft 98 rotating on which are the pulleys 100 between one tooth 94 and another.

The cord 24, from its point of departure 172 on the base slat 170, passes through the holes 22 in the slats 20 and then through the hole

42 in the plate 40 lying along the lower channel 36 in the box 30. The cord 24 then makes a first turn 180 (Figure 3) round the pulley

64 of the set of pulleys 60, and on to pulley 104 in the carriage 90, returning to pulley 63 on the first headpiece 50, makes a second turn 182 round the pulley 103 in the carriage 90 and is fixed by a knot 80 in the hole 73 in said first headpiece 50.

Cord 26, from its. point of departure 174 on the base slat 170, passes through the holes 22 in the slats 20 and hole 44 in the plate 40, makes a first turn 184 round the pulley 65 in the first headpiece 50 and round pulley 105 in the carriage 90, returning towards pulley 66 in the first headpiece 50, then makes a second turn 186 round pulley 106 in the carriage 90 and becomes fixed by a knot 82 in the hole 76 in the first headpiece 50. The second headpiece 120 is mounted on the second end of the box 30 across the upper channel 34.

Said second headpiece 120 presents two bodies 122 and 124 separated by the central passage 125. The first body 122 presents shaped side pieces 126 with cavities 127 (see enlargement) about as wide as the width of the chain 150.

The passage 125 connects with the first crosswise channel 128 in which there is a slot 132, and with the second crosswise channel 130 also with a slot 134. The first branch 156 of the chain 150 passes round the horizontal pulley 112 placed inside the seat 110 in the carriage 90 and then in the cavities 127 in the side pieces 126 in the first body 122. These cavities 127 permit the chain 150 to enter but prevent it from sliding axially due to the presence of the little balls 152 placed at regular intervals along the whole length of said chain 150. The second branch 158 of the chain 150 passes along the passage 125 between the first body 122 and the second body 124 in the second headpiece 120, and from there inside one of the crosswise channels 128 and 134 to move the blind when a pull is made on the handle 160 situated to the right or left of the blind. In Figure 2 the chain 150 is shown passing inside the channel 128. When the chain 150 is pulled obliquely from vertical, it slides freely in channel 128 (or 130), but when it falls vertically, one of the balls 27 is retained in the bottom of the slot 132 (or 134). This blocks the chain and also the blind in its extended position. A pull on the handle 160 causes the carriage 90 to move for a length about half that made by the handle, due to the turn made by the two branches 156 and 158 of the chain 150.

The movement made by the carriage 90 determines movement by the blind four times greater than carriage movement because of the turns 180, 182, 184, 186 respectively made by cords 24 and 26.

It follows that each movement made by the handle 160 corresponds to a blind movement of substantially, double the length due to the simultaneous effect of the reducing mechanism on the chain 150 and of the multiplying mechanism on the cords 24 and 26. Figure 4 shows an alternative version consisting in application of a double manual control 160 and 162.

Branches 156 and 158 of the chain 150 both pass in the passage 125 between bodies 122 and 124 of the second headpiece 120 and slide out through the openings 132 and 134 in the crosswise channels 128 and 130 at the sides 1, 2 and 144 of the upright 140. Means of anchorage 164 and 166 comprising narrow slots 168, are mounted on said sides 142 and 144 to allow the chain 150 to pass but not the balls 152. One of the branches 156, or 158, of the chain can therefore be left anchored at one of the sides of the upright 140, and the blind be moved using the other branch, by the respective handles 160, 162. The position of the blind, either extended or closed, is stabilized by fixing the second branch of the chain in its corresponding means of anchorage 164 or 166.

Claims

1. System for working vertically-operated blinds, characterized in that a reducing mechanism is combined with a multiplying mechanism.

2. System for working blinds as in claim 1 , characterized in that the multiplying mechanism is created by joining the blind to an upper box by means of a number of cords each of which, starting from a base slat, winds around a pair of pulleys freely turning round two crosswise shafts respectively supported by a first headpiece mounted at one end of the upper box and by a carriage translating freely inside said box.

3. System for working blinds as in claims 1 and 2, characterized in that the multiplying mechanism makes possible multiplication values according to the number of pairs of pulleys respectively supported by the first headpiece and by the carriage, the cords from the base slat being wound round said pulleys.

4. System for working blinds as in claim 2, characterized in that the blind has two or more cords according to its width.

5. System for working blinds as in claims 1 and 2, characterized in that the reducing mechanism is created by connecting the carriage to an operating chain departing from a second headpiece mounted on the second end of the upper box, a first branch of said chain winding round a horizontal pulley freely rotating inside the carriage, a second branch of the chain, substantially parallel to the first branch, emerging from the carriage, returning to said second headpiece and from there issuing vertically to be pulled and so operate the blind.

6. System for working blinds as in claim 5, characterized in that in the second headpiece is a central passage for the second branch of the chain, said passage connecting with a first and second crosswise channel extending respectively towards either side of the headpiece, through which the chain emerges and is then worked as required to the right or left of the blind.

7. System for working blinds as in claim 6, characterized in that the end of the branch of the chain emerging from the second headpiece on the upper box is joined to a handle for the use of the person working the blind.

8. System for working blinds as in claim 5, characterized in that the chain for working the blind presents a series of little balls placed at regular intervals along its length.

9. System for working blinds as in claim 6, characterized in that the crosswise channels connecting with the central passage in the second headpiece terminate in a slot of a size larger than that of the chain but smaller than the diameter of the balls so that if the chain is pulled slightly obliquely out of the vertical, it can freely slide to raise or lower the blind, but operating it vertically, causes one of the balls to be retained in the bottom of the slot so fixing the blind at the desired height.

10. System for working blinds as in claims 5 and 6, characterized in that the two branches of the chain pass along the central passage of the second headpiece, one branch emerging through the opening in the first crosswise channel and the other branch through the opening in the second crosswise channel, there being placed at the openings of said crosswise channels, an upright having respectively at either side a first and second anchoring device comprising a narrow slot that allows the chain itself to pass but not the balls, it being thus possible to anchor the first branch of the chain to a first anchoring device and work the blind using the second branch of the chain, also provided with a handle, and therefore fixing the blind at the desired height, inserting said second branch of the chain in the slot of the second anchoring device, so that the blind can be worked as preferred from inside or outside the house.