GB2373809A - Variable position window blind suspension system - Google Patents

Abstract

A suspension system for window blinds, screens, panels or other similar devices including a flexible continuous loop 1 supported by pulley wheels 2, 4 and carrying attachment fittings 6 to which a base element of a window blind or other device 7 can be affixed in such a way that the base element 7 can be moved to various positions within the system and secured in those positions by a locking device 8. This locking device may comprise a ball chain which engages with a constricted slot. Weights may be attached to the suspension loop 1 to counterbalance all or part of the weight of the base element.

Description

VARIABLE POSITION WINDOW BLIND SUSPENSION SYSTEM This invention relates to a method of suspending a window blind or other such device In such a way that the base element of the blind or device can be moved at will to various positions Window blinds of all types consist of a base element (roller, track, rail etc. ) fixed at a single position in an opening from which the blind is extended to cover the opening in order to achieve partial or full exclusion of light, to shade the sun or provide privacy. The fixing position of the base element is most usually at the top of an opening but it can alternatively be placed at the bottom or at an intermediate point. The disadvantage of this fixed position is that, although such shading or closure may only be required over a small area, the blind may have to be extended to cover most or all of the opening thus obscuring more of it than is desired.

An object of this invention is to enable the suspension point of the base element of the blind to be variable in that it may be moved to any required position by operation of a mechanism so that the blind need be extended sufficiently to cover only the required area, leaving the remainder unobstructed. The invention is described herein principally as applied to the suspension of window blinds but it can equally be used for other similar circumstances requiring variable positioning such as display panels, screens, advertising hoardings and the like.

A further object of this invention is to enable the suspension mechanism to be operated quickly, accurately and conveniently whilst remaining aesthetically pleasing.

Accordingly, this invention provides a suspension system including a continuous flexible nonextendible loop of cord, rope, cable tape or chain diverted over fixed rotatable pulley wheels and having fittings for attachment to a suspended element in such a way that the attachment fittings are supported but can be moved and are constrained to move by equal amounts in the same direction. Also included is a mechanism to produce a tensile force in the suspension loop in order to provide the correct conditions for effective operation of the system The invention further includes an operable clamp or stop device acting upon the suspension system in such a way as to prevent it moving except when the clamp or stop is released to allow movement.

An optional but non-essential addition to the invention to enhance its operation includes the provision of weights being of a suitable mass and attached to the suspension system in such a way as to counterbalance all or part of the mass of the suspended element and thus reduce the operating force required to move it.

A preferred embodiment of the invention will now be described with reference to the accompanying drawing numbered 1/1 in which: FIGURE I is a schematic diagram showing the relationship of the principal elements FIGURE 2 is an alternative detail for Fig. I including a counterbalance weight FIGURE 3 shows the elevation of a typical blind suspension system fitted to an opening FIGURE 4 is a detail of part of the suspension system FIGURE 5 is an enlarged detail of the lower return pulley FIGURE 6a shows the lower return pulley assembly with a possible stop mechanism FIGURE 6b shows the stop mechanism in the released position As shown in Fig. I the layout of the system comprises a continuous flexible loop 1 supported on pulley wheels 2 securely attached to the basic structure 3 to which the system is to be affixed. The ends of the loop I pass around lower return pulley wheels 4 each of which is attached to the basic structure 3 by means of an adjustable tensioning device 5 Securely attached to the suspension loop 1 are two attachment fittings 6 to which the base element 7 that it is required to suspend is firmly secured. The attachment fittings 6 are positioned on the suspension loop 1 at such positions that any movement of one attachment fitting produces a movement in the other one which is of equal distance and in the same direction as the original movement The loop 1 has at an optional position along its length a lock or clamping device 8 which normally prevents the system from moving but which can be operated to release the loop 1 in order to allow the base element 7 to be moved to the required position at which point the clamp or lock is re-applied to maintain the base element in the selected position.

Shown in Fig. 2 is an optional addition to the system to enhance its operation whereby a number of weights are attached to the suspension loop 1 (Fig. 2 shows only one side of the system whereas this detail would be repeated on the other side not illustrated). The weights 9 would be attached to the loop in such a position and be of sufficient mass approximate to the weight of the suspended base element and device in order to produce a counterbalance effect thus reducing the operating force required to move the base element.

Fig. 3 represents a typical application of the invention in that it shows a sytem applied to an opening inasmuch as all the elements described in Fig. 1 are securely attached to the opening 3. Also illustrated in Fig. 3 is a partially deployed window blind lOa and lOb (chain dotted) These blind positions shown are exemplary only, the blind being capable of covering most of the opening Fig. 4 shows the view on arrow A in Fig. 3 and illustrates the alignment of the side of the suspension loop 1, pulley wheels 2 and 4, tension device 5 and the base element 7.

Shown in Fig. 5 is an enlarged detail of the view on arrow B in Fig. 3 which shows the lower return pulley wheel 4 carried in a frame 11 which is in turn attached to the basic structure 3 via a tensioning device 5. In Fig. 5 the tensioning device is illustrated as an extendable spring but it could equally take the form of an adjustable screw or any other such device.

Also illustrated in Fig. 5 and Figs 6a and 6b is a modification designed to produce a locking action to hold the suspension loop in the desired position. The portion of the suspension loop 1 which passes around the lower return pulley is modified to be constructed as a ball chain of known design made from metal or plastic whereby evenly spaced spherical balls are flexibly connected by links of smaller dimension than the diameter of the balls. This modification is illustrated as la and 1 b in Fig. 5.

To produce the required locking action the frame 11 on one side only of the system is modified as shown in Figs. 6a and 6b which are views on arrow C in Fig. 5. In this one side of the frame has an elongated slot 12 the width of which is greater than the link of the ball chain la/lb but less than the diameter of the balls of the said ball chain. The frame 11 is constructed of material which is thin enough to pass freely between two adjacent balls of the ball chain but which is also strong enough to resist any force in the system due to the weight of the elements or the operation of the blind or suspended device. When the system is at rest the ball chains la and lb adopt the positions shown In Fig. 6a in which the ball chain lb engages with the slot 12 thus preventing any movement of the suspension loop 1.

To release the locking action and enable the loop to be moved as required the ball chain is deflected by the person operating the system into a position indicated by the chain dotted line 13 in Fig. 5. This has the effect of moving the ball chain lb to the position indicated in Fig. 6b thus disengaging it from slot 12 and so allowing the loopl to be moved as required.

When the deflection of the ball chain I b is removed it returns to the original position in which it re-engages slot 12 and thereby locks loop 1 against further movement.

The locking mechanism described above is one example of the device 8 but this may equally be achieved by the use of any clamp or cleat of known design which is applied to loop 1 to prevent its movement when so required.

Claims (4)

1. CLAIMS l. A suspension system for window blinds, screens, panels or other similar devices including a continuous flexible loop of cord, rope, cable, tape or chain diverted about and supported by rotatable pulley wheels and restrained by an operable locking mechanism so that an attached suspended element can be moved to various positions at will whilst being constrained in a single attitude.
2. 2. A suspension system as claimed in Claim I where weights are attached to the suspension loop so that they counterbalance part or all of the weight of the suspended element.
3. 3. A suspension system as claimed in Claim 1 provided with a loop locking mechanism including a ball chain which engages a constricted slot to achieve locking restraint of the system.
4. 4. A suspension system substantially as described herein and illustrated in the accompanying drawings.