A SYSTEM FOR ELEVATING AND LOWERING A LIGHT AND/OR VISION

IMPEDING ARRANGEMENT

The present invention relates to a system for elevating and lowering a light and/or vision impeding arrangement such as a blind.

Blinds traditionally hang at the top of a window and are lowered for use. The blind will then impede visibility and incidence of light from above and down, as the blind is lowered in of in front of the window.

Basically, there is two systems for this type of blinds:

A first system where the blind is mounted in the wall over a window and where the mechanism for elevating and lowering the blind is held in a closed bar extending over the window.

A second system where the blind is mounted in the window frame, that is between two window panes, for example between the glasses in a double-glazed window. The elevation and lowering device of this system can be integrated in the window frame. This system can also be used with stand-alone windows not being mounted in a wall.

It is often a preference to prevent visibility through the lower part of a window, while the upper part of the window at the same time allows light to enter. To this end, it is developed a blind system where the blind is arranged with strings passing through the entire blind and being attached to the upper edge of the window frame. By pulling the strings, it is possible to elevate and lower the blind. A disadvantage with such systems can be a difficulty to lower the upper edge of the blind completely or principally parallel. This may result in that the lamellas fold in an inappropriate way or that the blind jams in the window panes. With blind, it is meant a number of parallel lamellas being tillable to adjust the degree of visibility and incidence of light.

The present system or arrangement is well suited for plisse curtains or the like. For the arrangement to be used with blinds, in addition to a string system for elevating and lowering the blind, it is requisite to provide a system for tilting the blinds. There is a need for such systems not having a complicated structure giving high production costs. There is also a need for such systems which are not demanding a window frame of a certain magnitude to hold the system.

In window panes in general and especially in stand-alone windows, it is desirable to give an open impression when the blind is folded down in the lower part of the window frame. Therefore, strings for elevating and lowering the blind passing over the open window surface are not desirable.

It is an object of the present invention to present a system for a blind or other type of curtain, which can be elevated and lowered from below and where the system for elevating and lowering of the blind is not visible when the blind is folded down.

Furthermore, it is an object to present an integrated system which elevates and lowers the blind and which is also able adjust the angle of the lamellas of the blind.

It is also an object to present a compact system for mounting and use with blinds in a window frame or other equivalent frames, in other words an arrangement which do not require a solid window or frame structure, large free spaces or extra adaption of any structure surrounding the blind. It is also an object to present a system where the mechanism for elevating and lowering the blind elevates and lowers the blind principally or completely parallel, so that a possible jamming or incorrect folding of the lamellas is avoided or minimised.

It is also an object to present an arrangement for blinds which can be used with standalone installations in an opening, possibly in front of or between two glasses in a partition wall system or between the glasses in a double-glazed window.

This is obtained by the present invention as defined in the attached set of claims.

The invention relates to a system for elevation and lowering of a light and/or vision impeding arrangement such as a blind or the like which is arranged in a frame comprising an upper and a lower horizontal profile and two transverse or perpendicular profiles arranged to form a quadrangle frame. The system further comprises a rod or other elongate element from which guiding strings are suspended. A blind is also connected to the rod. The rod is further connected with an elevation and lowering mechanism lifting and lowering the rod simultaneously with the blind being lifted or lowered. In the system according to the invention, the rod is connected to two devices arranged in the transverse profiles whereby the blind is lifted or lowered when the devices are lifted or lowered.

In a system according to the invention a movable device such as a carrier is attached to a belt being connected to at least one drive wheel moving the belt. The movable device comprises a rotatable wheel being connected to the belt in such a way that the rotatable wheel can rotate when the belt is moving.

In an embodiment of the system according to the invention, the rotatable wheel arranged in or at the carrier, is connected to the rod in such a way that when the rotatable wheel is rotating, the guiding string will be lifted or lowered respectively so that the lamellas of the blind are tilted to one side or the other.

The system according to the invention can also comprise a motor with at least one protruding shaft. The shaft and, if appropriate, the motor is arranged in the upper horizontal profile in such a way that the shaft or shafts is/are in contact with the upper drive wheels being arranged in the two upper corners of the frame, in such a way that the drive wheels rotate when the shaft or shafts rotate.

In an other embodiment of the system according to the invention, a U-formed profile is arranged partly surrounding the rod. The profile is provided with supporting brackets being attached to the profile in such a way that a part of the profile and one bracket together form an enclosure for a part of the rod.

On other words, a system or arrangement according to the invention comprises a blind being attached at the lowest part of the window. The blind can be elevated for use to prevent visibility in the lower section of the window, while it allows light to enter through the upper section. The lamellas of the blind can be parked in any intermediate position and be tilted to any angle.

The blind arrangement furthermore comprises a frame wherein the mechanism for elevation and lowering is mounted. The upper edge of the blind is attached to a transverse strip or rod that can be lifted or lowered by the elevation and lowering mechanism. Thereby, there will not be any part of the elevation and lowering mechanism over the upper edge of the blind.

Further advantages and details with the present invention will be described with reference to the attached drawings where: Fig. 1 shows a perspective view of the system according to the invention. Fig. 2 shows a cross section of the elevation and lowering system. Fig. 3 shows a cross section of the blind being attached to the elevation and lowering

mechanism.

Fig. 4 shows a cross section of a part of the blind arrangement.

Fig. 1 shows a perspective view of the arrangement according to the invention. A window frame with an arrangement according to the invention comprises four profiles; an upper profile 1 and a lower profile 11 being paralle to each other and two transverse profiles 4 parallel to each other and perpendicular to the upper 1 and lower profile 11. The profiles are only partly shown in the figure. The four profiles extend over the length of the blind arrangement and will form a quadrangular frame. The profiles can for example be made of extruded aluminium or rolled steel plates being folded and/or welded together. The material used for the profiles should be rustproof and preferably of a certain strength. High-strength plastic material might also be useable for the window frame or other parts of the arrangement.

A strap or belt 5 is arranged in each of the vertical profiles. The belts can be a transmission belt, toothed belt, friction belt, chain, wedge belt or the like being suitable for running one or more wheels or other rotating elements such as a shaft or rod. The belts 5 are arranged on and gripping upper and lower drive wheels 3 being provided in the corners of the frame.

A motor 10 is mounted in the upper horizontal profile. The motor run the drive wheels 3 via two shafts 13 or one long shaft passing thorugh the motor 10. If there are two shafts 13, they will project from the motor on each side of the motor. Thereby, the two upper drive wheels 3 are synchromesh and will enable a completely or principally parallel lifting and lowering of the two mounting regions of the upper edge of the light and vision hindering device, e.g. the blind. In the lower horizontal profile 11, a shaft 12 can be arranged connecting the lower drive wheels 3, but this is not necessary for the invention to function in accordance with the intentions.

A transporting or carrying device such as a carriage or carrier 6 is arranged on each of the belts 5 as shown in figure 1, 2 and 3. The free ends of the belts 5 are coupled to the carrier 6 through openings or slots 17 in the carrier 6. There is also arranged a through- going passage 16 in the carrier 6 through which the belt 5 can pass. When the motor is running, the drive wheels 3 will turn and the carrier 6 will move upwards and downwards in the profiles 4. As the carrier is lifted or lowered, the belt 5 will pass upwards and downwards through the passage 16.

A rotatable wheel 7 is arranged in the carriers 6 in movable contact with the belt 5 e.g. by friction. When the belt 5 moves through the passage 16, it will start rotation of the rotatable wheel 7. The rotatable wheel is arranged so that it will slide when a given resistance is reached, for example when the lamellas of the blind reaches their maximum angle.

The rotatable wheel 7 holds a shaft or rod 8 forming the upper part of the blind where the attachment strings for holding the lamellas 9 are arranged, preferably in a permanent way. The rod 8 is advantageously made from a sylindrical element such as tube, for example made of light metal. When the carriers 6 are lifted or lowered, the rod 8 being attached to the carrages, will follow the carriers up ad down and thereby lift and lower the blind. When the blind has reached a desired level, it is possible to adjust the angle of the lamellas by changing the direction of the movement of the motor 10 and thereby of the belt 5.

When the motor is running, it will turn the shaft 13, which in turn rotates the upper drive wheels 3 moving the belt 5, so that the carriers 6 where the blind is attached, are elevated or lowered. When a desired level of the blind is reached, the motor is stopped or reversed as the motor also can be used for adjusting the angle of the lamellas.

Figure 2 shows how the blind is arranged in the system or arrangement according to the invention. When the motor is rotating, the carriers 6 will be elevated or lowered. The shaft 8 following the movement of the carrier 6 will rotate together with the wheels 7 as described above. Due to this rotation, a guiding string 18 provided in the blind will be pulled towards one or the other side and the lamellas 9 in the blind will move or tilt from side to side so that the blind will close or open. The lamellas can be arranged or tilted in any desired position by running the motor back and forth.

It is advantageous to arrange a U-formed profile or moulding 19 partly surrounding the rod 8, as shown in fig. 4. The profile 19 will extend from one of the vertical frame profile 4 to the other vertical profile 4. The profile 19 can be attached to the carriers 6 over the rod 8. The blind is hanging from the rod 8. To prevent the rod 8 from distorting due to the weight of the blind, the tube-shaped rod can be supported by means of the profile 19, being attached on each side of the carriers 6. Small holders or brackets 20 are provided in the profile, uniformly distributed over the length of the profile 19 and supporting the rod 8. This will prevent the rod 8 from distorting over time due to the weight of the blind, as the brackets contribute to weight distribution and bracing over the connecting points.

In the shown embodiment, the belts 5 are extending over the whole length of the vertical profiles 4. By use of the system in cases where it is advisable or desirable to always keep a part of the window surface open, for example in stand-alone partition walls, it is possible to envisage a solution where the belt is only reaching a certain height in the frame 4 and where the upper drive wheels 3 are arranged at this height. In such cases, the motor running the system must be arranged in the lower horizontal profile 11. The system will otherwise function as described above.

If it is required to use even less space than required by the arrangement as described above, it is possible to arrange the motor outside the frame with a transmission arrangement transmitting the rotational movement from the externally arranged motor to the shaft 13 moving the drive wheels 3.

In the described embodiment, the system or arrangement is shown for blinds of the lamella type, but the system or arrangement can also be used with other light and/or visibility preventing devices such as fold or plisse curtains.