TECHNICAL FiELD

The invention relates to a system comprising a plurality of slats for use for instance in a shutter, panel or Venetian blind, which might be used for instance but not exclusively to cover window portions or other openings of a building

BACKGROUND OF THE INVENTION

Vertical Venetian blind systems are known which are provided with slats that can be displaced over the system for instance by application of a pantograph mechanism. The slats of these systems can furthermore be tilted by means of a tilt mechanism comprising a spindle extending over all of the slats and being in engagement with a gear wheel mounted on the rotational axles of the individual slats Examples of such systems are disclosed in US 3,280,891 and US 5,819,833

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a system of slats for instance in the form of a shutter or a Venetian blind of the kind described above comprising a frame or sidepieces, encompassing or totally or partly defining an inner region, which can be covered more or less by a plurality of slats extending parallel with each other, where the slats can be displaced between a first extreme position, in which they are distributed over substantially the whole of said inner region and a second extreme position, in which the slats only cover a given section of the inner region It must further be possible to make the slats attain intermediate states of coverage, where smaller or larger positions of the inner region are covered by the slats. According to a specifically advantageous embodiment of the system according to the invention, it must be possible to orient the system in such a manner that the slats extend vertically above each other, i.e the slats extend horizontally as well as In traditional Venetian blinds as side by side, i.e. with the slats extending vertically Furthermore, all

conceivable intermediate states of orientation of the system must be possible, without this affecting the proper functioning of the system. Furthermore, it must be possible for the plane of the system to extend at any angle relative to the horizontal, for instance vertically as in connection with a traditional window or at an oblique angle as in connection with an inclining window.

It is a further object of the present invention to provide a mechanism for displacement of slats over said inner region of the system, so that throughout the displacement, i e. with any position of the slats relative to the frame or sidepieces, a well-defined distance between the individual slats is provided or maintained

It is a further object of the present invention to provide a tilt mechanism for tilting the slats relative to the plane of the system (shutter, Venetian blind etc ) The tilt mechanism must function regardless of the state of extension of the slats over the inner region of the frame, i.e regardless of where the individual slat is located within this region.

The above and further objects are according to the invention attained by a system either comprising a at least partially hollow frame comprising two sidepieces through which rotational axles of the slats are passed or in stead of said completely encompassing frame comprising only the said sidepieces Said rotational axles are within the sidepieces in engagement with a pantograph mechanism, in itself known from a number of applications also within other technical fields (for instance a pair of sugar tongs) and which will be described in depth in the detailed description of the invention . The pantograph mechanism comprises thus as known a number of cross- sections, where the crosses in these sections regardless of the total extension of the pantograph mechanism in the ideal case of playiess bearings of the mechanism are all distributed equidistantly relative to each other. Thus, if the rotational axles of the individual slats are passed through the crossings of the pantograph mechanism, the distance between the rotational axles of the individual slats always remains the identical regardless of the total extension of the pantograph mechanism The pantograph mechanism is in this case dimensioned in such a manner that in its totally extended state said mechanism makes it possible for the slats to cover the whole inner region of the system and that the pantograph mechanism in the totally collapsed state on the other hand draws the slats so much towards each other that the slats cover the desired portion of the inner region.

Furthermore, the rotational axles of the individua! slats are passed rotatabSy through the crossings of the pantograph mechanism, such that the slats can be brought to rotate about their longitudinal axis regardless of the state of extension of the pantograph mechanism.

The tilt mechanism for the slats can be provided in a number of ways of which a single, presently preferred embodiment will be described in the detailed description of the invention. It is emphasised that although the tilt mechanism of the present invention is described specifically in connection with a system comprising a pantograph mechanism, the tilt mechanism according to the invention could also be applied in other systems of slats, which are to be tilted, for instance other forms of shutters or Venetian blinds, which do not comprise the pantograph mechanism described in the present specification.

BRiEF DESCRIPTION OF THE DRAWINGS

The present invention will be better understood by reference to the following detailed description of an embodiment of the invention comprising a shutter with pantograph and tilt mechanisms and with reference to the appended drawings, where

figure 1 shows a schematic representation of a shutter according to the invention in a state where the slats are distributed evenly over the open inner region of the frame;

figure 2 shows a schematic representation of the shutter of figure 1 but with the slats drawn together such that they only cover a partial region of the total open region within the frame;

figure 3 shows a schematica! perspective view of a portion of a sidepiece of the frame and the pantograph mechanism and associated slats in the shutter according to the invention;

figure 3a shows a preferred embodiment of the lever in the tilt mechanism;

figure 3b shows a special design of end portions of the crossings of the pantograph mechanism; figures 4a, b, c and d show alternative displacement mechanisms for displacement of the slats over the inner region of the shutter.

DETAILED DESCRIPTION QF THE INVENTION

Referring to figure 1 there is shown an embodiment of a shutter according to the invention generally designated by reference numeral 1 and comprising a at least partially hollow frame 2 comprising juxtaposed sidepieces 2' and top and bottom portions 2", In the inwardly facing portions of the sidepieces 2', an elongated opening or recess 14 serving as guide tracks for the rotational axes of the individual slats is provided extending longitudinally in the sidepieces 2' to such an extent that the slats 3 (or rather their rotational axes) can be displaced sufficiently in these to be able to cover the inner region of the frame or a desired portion hereof The rotational axles 4 of the individual slats 3 are passed through these elongated openings/guide tracks 14 and into the hollow interior of the frame.

In figure 2 the same shutter as in figure 1 is shown but with the slats displaced in such a manner that they only cover substantially the upper third of the inner region of the frame.

Referring to figure 3 the initially mentioned pantograph mechanism and the tilt mechanism will be described in detail. Figure 3 only shows one of the sidepieces 2 ^! of the frame 2, The juxtaposed sidepiece can be designed similarly, but according to a preferred embodiment of the invention the juxtaposed sidepiece comprises only the pantograph mechanism, while the tilt mechanism is only provided in one of the sidepieces. Figure 3 shows the guide track or longitudinal opening 14 through which the rotational axles 4 of the individual slats 3 are passed Within the hollow portion of the sidepiece 2', the said pantograph mechanism designated by reference numeral 5 is provided, which mechanism as shown is composed of a series of cross-sections 5', through the central, crossing part of which the rotational axles 4 of the slats 3 are passed, so that these are freely rotatable in the crossings of the pantograph mechanism. At the end of the rotational axles, a lever 8 is located, said lever at the end of the arm that is positioned farthest away from the rotational axle being provided

with a first pin or roller 9. When the lever 8 is tilted as shown by the arrows B, the corresponding slat is tilted In the embodiment shown in figure 3, said first pin or roller 9 is in engagement with a groove 10 of substantially the same width as the diameter of the pin or roller 9. The groove 10 is provided in a bar 1 1 extending in the longitudinal direction of the sidepiece 2', which bar 11 can be displaced both longitudinally and laterally in the sidepiece 2' The lateral displacement is indicated by the arrows A in figure 3 In order to attain the simultaneous displacement longitudinally and laterally in the sidepiece 2', the bar 1 1 is on the face hereof away from the groove 10 provided with another pin or roller 13, which can be displaced in an oblique groove or track 12 provided in the outer face of the sidepiece 2 ¹ . The oblique groove or track need not necessarily be visible from the outside of the sidepiece 2, or be provided in the sidepiece at all, but may be provided in a separate member, which may be displaceably connected to the inner face of the sidepiece in such a manner that it is not visible from the outside. The displacement of the second pin or roller 13 in the groove 12 thus provides the simultaneous displacement of the bar 1 1 longitudinally and laterally in the sidepiece 2', and thus results through the engagement between the first pin or roller 9 on the lever 8 and the groove 10 in the bar 1 1 in the desired tilting of the slats 3- As the bar 1 1 and the groove 10 extend longitudinally throughout the entire system of slats, the tilt function will be operative regardless of where the individual slats are located within the frame. The groove 12 can in principle extend at any angle α between 0 and 90 degrees relative to the longitudinal axis of the sidepiece 2', although from a practical point of view it has been shown to be advantageous if this angle is in the order of magnitude of 30 degrees.

In order to ascertain that the levers 8, and hence the slats even in the most collapsed state of the pantograph mechanism can be tilted over the largest possible angular interval and in order to ascertain that the Severs 8 can be made as long as the hollow interior of the sidepieces allows, it is advantageous to design the levers as shown in figure 3a, I e. with a bended middle section joining two substantially parallel distal sections receiving the rotational axle 4 of the slat and the tip or roller 9, respectively.

It is furthermore advantageous if the ends 28 of the individual crossings of the pantograph mechanism as shown in figure 3b are pointed and/or that the diameter of the corresponding bearings 29 are made as small as possible. Other means of optimising the design of the pantograph mechanism and the levers 8 are conceivable,

which are regarded to be within the scope of the present invention as defined by the appended claims

As mentioned initially, the pantograph mechanism 5 will in principle cause the distance between the points where the rotational axles 4 of the slats 3 are passed through the crossings to remain the same for all slats for any extension of the pantograph mechanism Thus, when the pantograph mechanism is retracted from its maximally extended state, where the slats cover the whole of the inner region of the frame, to a more collapsed state, the same distance will in principle always be provided between any neighbouring slats regardless of where in the system of slats these are located.

The slats thus remain evenly distributed over that portion of the inner region of the frame, which is covered by the slats

Referring to figures 4a, b, c and d, different ways of operating the pantograph mechanism according to the invention will now be described. It is understood, however, that these alternative operational means are intended as examples only and that a person skilled in the art may devise further alternative means to drive the pantograph mechanism, without such means falling outside the scope of the present invention as defined by the appended claims. Which of the described operational means will be preferred will furthermore depend on the specific application of the shutter, for instance of its orientation (horizontal/vertical slats, vertically mounted shutter, horizontally mounted shutter, shutter extending in an oblique plane as for instance in an oblique window such as a skylight, etc ), because the force of gravity acting on the slats at certain orientations of the shutter will affect the displacement of the slats and thus the function of the pantograph mechanism, while other orientations of the shutter will lessen or totally eliminate the effect of the force of gravity on the displacement of the slats.

In figures 4a, b, c and d reference numeral 15 generally designates a fixed connection to the relevant part of the frame. As appears, one distal crossing point 15 of the pantograph mechanism 5 will in all of the shown embodiments be fixedly connected to the frame by attachment means allowing a corresponding slat to tilt over the desired angular interval.

Figure 4a shows a first embodiment of drive means for the pantograph mechanism The pantograph mechanism is in suspended form 15 (the direction UPWARD is

indicated in the figure) and two lift cords 16 are attached to the lowermost crossing at 17, The lift cords 16 may be passed through suitable guide means 18 at the other crossings as shown. The lift cords 16 will be connected to suitable drive means (not shown in the figure) provided in the top portion 2" of the frame, for instance comprising a motor, which via a suitable transmission drives a drum for winding/unwinding of the lift cords. When the drive mechanism is activated, the lift cords 16 will retract (collapse) the pantograph mechanism in an upward direction and conversely the force of gravity acting on the slats will be utilised for the downward movement of the slats

In figure 4b an alternative way of operating the system is shown, the system still being suspended from a fixed point 15 and thus for the downward movement of the siats still at least to some extent relying on the action of gravity on the siats. In this embodiment, the two lift cords shown in figure 4a are replaced by a single lift cord 19, one end of which is attached to the top portion 2" of the frame and which via suitable guide means 20 is passed over a spool or pulley 21 attached to the lowermost crossing, from which the iift cord 19 via said guide means 20 is passed to a drive mechanism, for instance of the kind described in connection with figure 4a. Without this being actually shown, it should be mentioned that by suitable use of spools/pulleys at both ends of the lift cords this embodiment could be extended to a tackle system facilitating lifting of the slats

While the two embodiments described above specifically addressed vertically mounted (or at any rate highly oblique) systems comprising substantially horizontally extending slats (i.e. Venetian blind type of systems for vertically extending windows or oblique windows extending at a substantial angle relative to horizontal), the embodiments of drive means can for the pantograph mechanism in principle be used regardless of the orientation of the frame or slats, these embodiments not relying on the effect of gravity on the slats.

Thus, figure 4c describes the pantograph mechanism 5 fixedly connected at 15 and driven by the displacement cords 22 and 23, which similarly to the system shown previously can be passed through guide means 20- The displacement cord 22 is at reference numeral 17 attached to a crossing located farthest away from the fixed connection point 15 The displacement cord 23 is possibly via the guide means 20 passed over a spool or pulley 24 attached to the frame at 15' opposite the fixed connection point 15 and from there to point 17. A pull in the displacement cord 22 will

thus result in an extension of the pantograph mechanism. This means of operation is of course in principle independent on the effect of gravity and functions regardless of the specific orientation of the frame and the slats herein.

it should be noted that the expression "cords" as used in this specification is to be construed as any flexible means being able to perform the function of a cord. Thus, for instance chains will also be encompassed by the term "cords", and in connection with big and heavy shutters and slats it could prove advantageous actually to apply chains in stead of cords

An alternative mechanism for driving the pantograph mechanism, which wiil also function independent on the effect of gravity on the shutter and the slats, is shown in figure 4d. According to this embodiment of the invention, the lift or displacement cords of the preceding embodiments are here replaced by spindle or threaded rod 25, which may be passed through guide means 20 at the individual crossings and which at the crossing farthest away from the fixed connection point 15 of the pantograph mechanism is passed through a threaded member 26 attached to that end of the pantograph mechanism located farthest away from the fixed connection point 15 The spindle 25 may possibly by supported by a bearing 27 attached to the frame. When the spindle 25 rotates in one direction, the pantograph mechanism will be extended and an opposite rotation of the spindle will cause the pantograph mechanism to be retracted or collapsed

It should furthermore be noted that even though the displacement means (i.e. the lift or displacement cords 16, 19, 22 and 23 and the spindle 25) have in the preceding been described as acting on the crossing furthest away from the first crossing 5' in the pantograph mechanism, these displacement means can in principle be connected to any of the crossings in the pantograph mechanism and still lead to the above described displacements of the pantograph mechanism and hence of the slats. The displacement means furthermore need not act on the outermost part of the crossings

(as shown in figure 4a) or on the central parts of the crossings (as shown in figures 4b, c and d) but may in principle act on any part of the crossing

It should furthermore be emphasised that even though the present invention has in the preceding been illustrated in the form of a shutter comprising a frame encompassing the whole open inner region of the frame, the invention also relates to systems solely

comprising the two sidepieces 2', wherein the pantograph and tilt mechanisms are located. These sidepieces will in this case each be attached to the building or window, etc