(roller) shade, a (roller) shutter, or the like, comprising:

- a cover element, such as a roller blind, a shade, a shutter, or the like;

- a rotatable element to which said cover element or a means for retracting and extending said cover element is wounded, said rotatable element being rotatable in a first direction for winding up said cover element or said means for retracting and extending and in a second, opposite direction for unwinding said cover element or said means for retracting and extending, and

- a motor for rotatingly driving said rotatable element in the first or second direction. It is noted that said cover element is not the actual window or door, but a cover for covering said window or door.

Such a cover system is known per se. Currently cover systems are running at a uncontrolled RPM speed or at fixed RPM speed. The speed of the closing profile depends on many aspects, wherein the diameter of the rotatable element including the number of windings that are still present on the rotatable element are dominant to convert vertical or horizontal travelling speed against the rotation speed of the element.

It is an object of the invention to provide a cover system that allows the free end of the cover element or blind to travel with a constant speed, preferably completely independent of the blind mechanics and/or the thickness of the mounted cover element or blind and/or travelling wires and/or independent of actual temperature, ageing and/or similar effects on the actual screen.

This object is achieved by a cover system according to the preamble that is characterized in that said cover system comprises a (micro) processor for controlling said motor in such a way that said rotatable element is rotated with a first chosen speed such that a free end of the cover element is transported at a second chosen speed.

The first chosen (rotation) speed of the rotatable element determines the second chosen speed, which is the traveling or transportation speed of the free end of the cover element. Thus by choosing the first chosen speed the second chosen speed can be chosen. This allows for a number of cover elements, for example attached to a same side of a building, to be transported with a same second chosen speed, even if one cover is mounted higher or lower than another cover. There is no longer a matching height requirement between covers that are intended to operate in groupwise condition. In current systems the rotation speed of the rotatable element is uncontrollable or at most constant, such that the traveling speed of the free end is uncontrollable and/or not constant. In accordance with the invention the second chosen speed may be constant by choosing the first chosen speed correctly.

Being able to control the speed of the free end of the cover element according to the invention in particular may have an aesthetic purpose and not a safety purpose. As the cover element covers a window or door and is not the window or door itself, safety may generally not be an issue with the system according to the invention.

It is noted that said invention is in particular advantageous in cover systems using said rotatable element to which said cover element or a means for retracting and extending said cover element is wounded, as such cover systems do not have a linear relation between the rotational speed of the rotatable element and the speed of the free end of the cover element.

The second speed may be chosen as desired over the entire unwinding length of the cover element by choosing the first chosen speed correctly. For example, the second speed may be relatively slow at starting and/or stopping and may be relatively fast in a trajectory between the start and stop of the blind. In particular, said (micro) processor may be arranged for controlling said motor in such a way that at starting or stopping transportation of the free end of the cover element the transportation speed is gradually increased or decreased.

The invention connects the motor driver software to a set of manufacturing and commissioning parameters that offer real-time information to allow the motor controller to adapt its rotation speed exactly to actuate for a, preferably constant, travelling speed or second chosen speed.

In the current market this feature helps to overcome distance and travelling

synchronisation problems of parallel located blinds with different installation heights, different cover element materials and different travel length. It solves also the problem of vertical installation height misaligning as well as starting from different positions or stopping at different end-positions.

The cover element material may be (made of) any suitable material, such as, but not limited thereto, a woven, a non-woven, a foil, paper, textile, plastics, a mesh, or the like.

Limit setting tool for electrical operated blinds. When blinds of different sizes are installed beside each other the closing profile per blind runs each at a different speed depending on position. With this invention the running speed of the closing profile is constant and aligned for all blinds in the group independent to the tube diameter of the rotatable element, size of the blind and thickness of the cover element material. Said first chosen speed may be chosen in accordance with at least one parameter, said parameter(s) being chosen from the group comprising a diameter of the rotatable element, a length of the cover element, a total number of windings of the cover element, a number of windings of the cover element that is present on the rotatable element at a certain unwinding point of the cover element, the thickness of a material of the cover element, rotation accuracy and resolution of the rotatable element, the temperature of motor and gearbox, the temperature of the climate, the temperature of the cover element material of the winded cover element material, the temperature of the unwinded cover element material, the wearing conditions and number of travels of the mechanical parts and motor, relative and absolute humidity in the direct environment of the cover element material, the weight of cover element material, the weight of the end of the cover element, cover element material compression of the winded part of the cover element material.

For example, the first chosen speed is calculated by a quadratic or higher order equation from the second chosen speed taking into account any combination of parameters as describe above.

In an embodiment of the cover system according to the invention said cover system comprises a sensor configured for measuring the speed of the free end of the cover element. With such a sensor it is possible to determine whether the traveling speed of the free end of the cover element is as chosen, for example constant over the traveling distance. Such a sensor may be used at installing the cover system for checking whether it functions properly. The sensor may be a separate sensor, that may only be temporarily used during the installation and commissioning of the cover system.

In another embodiment of the cover system according to the invention said cover system comprises a sensor configured for measuring the presence of the free end of the cover element at a chosen reference position, wherein said (micro)processor is configured for calculating the speed of the free end of the cover element based on said measured presence and rotational angle of said rotatable element . The distance to the reference position is known. By measuring the presence of the free end at the reference position the time needed for traveling to this reference position is known. In combination with the rotational angle or number of rotations of the rotatable element the speed of the free end may be calculated. The rotational angle or number of rotations is provided by the motor, for example by a sensor of the motor. As with the speed sensor, this information may be used at installing the cover system for checking whether it functions properly. The sensor may be a separate sensor, that may only be temporarily used during the installation and commissioning of the cover system. In another embodiment of the cover system according to the invention the (micro)processor is configured for controlling said motor based on the measured or calculated speed.

In particular said (micro)processor uses a feedback loop wherein the measured or calculated speed is compared with the second chosen speed for providing a compared speed, and, optionally, adjusting the first chosen speed in accordance with the compared speed.

Said measured speed may be used for determining the first chosen speed and thereby the second chosen speed. In such an embodiment no other parameters may be required for calculating the first chosen speed except for the measured speed, and said first chosen speed is calculated based on the measured speed in a feedback loop. In this feedback loop the measured speed is compared to a second chosen speed of the free end, and the rotational speed of the motor is adjusted in accordance with this comparison. In particular, the first chosen speed is decreased if the measured speed is higher than the second chosen speed and vise versa. If the measured speed equals the second chosen speed no adjustment of the rotational speed of the motor is required.

Alternatively, the measured or calculated speed may be used for calibration and feedback only, whereas the first chosen speed is calculated using the parameter(s) as described above. This may for example be done at installing the cover system. If deficiencies in the speed of the free end are detected by the sensor, for example by comparing the measured or calculated speed with the chosen second speed, the speed of the motor may be adjusted via a feedback loop in order to correct these deficiencies. After calibration the sensor may optionally be removed. If re -calibration is required after time, the sensor may be provided again to re-calibrate the cover system.

In particular the invention may relate to a roller blind, comprising:

- a blind;

- a rotatable element to which said blind is wounded, said rotatable element being rotatable in a first direction for winding up said blind and in a second, opposite direction for unwinding said blind; and

- a motor for rotatingly driving said rotatable element in the first or second direction, characterized in that said roller blind comprises a (micro)processor for controlling said motor in such a way that said rotatable element is rotated with a first chosen speed such that a free end of the blind is transported at a second chosen speed.

Said first chosen speed may be chosen in accordance with at least one parameter, said parameter(s) being chosen from the group comprising a diameter of the rotatable element, a length of the blind, a total number of windings of the blind, a number of windings of the blind that are present on the rotatable element at a certain unwinding point of the blind, the thickness of a cover element material of the roller blind, rotation accuracy and resolution of the rotating element, the temperature of motor and gearbox, the temperature of the climate, temperature of the cover element material of the winded cover element material, the temperature of the unwinded cover element material, the wearing conditions and number of travels of the mechanical parts and motor, relative and absolute humidity in the direct environment of the cover element material, weight of cover element material, the weight of the end of the blind, cover element material compression of the winded part of the cover element material. Said first chosen speed may be calculated by a quadratic or higher order equation from the second chosen speed taking into account any combination of these parameters.

The invention also relates to a system, comprising a plurality of covers for a window or door, such as a (roller) blind, a (roller) shade, a (roller) shutter, or the like, according to any of claims 1 - 7, comprising communicating means for providing communication between the (micro)processors of the cover systems.

As each cover system has its own (micro)processor it is possible to control the rotational speed of each rotational element independently. This allows said cover systems to be controlled either simultaneously in groups or alone.

As a result of the communicating means it is possible for the (micro)processors of the various cover systems to communicate together, such that the free ends of the cover elements may be transported at the same transportation speed and/or at the same height, as is described above, by controlling the various cover elements simultaneously but independently.

The invention also relates to a method for measuring the speed of the free end of a cover element of a cover system according to claim 4, said method comprising the step of measuring said speed using said sensor.

The invention also relates to a method for measuring the presence of the free end of a cover element of a cover system according to claim 5 at a chosen reference position, wherein said (micro)processor is configured for calculating the speed of the free end of the cover element based on said measured presence and rotational angle of said rotatable element .

As described above, said measured or calculated speed may be used to check if the actual speed of the free end of the cover element is equal to or at least approximately equal to the second chosen speed. Such a check may be performed at installing the cover system.

In particular said method may comprise the steps of:

- comparing the measured or calculated speed with the second chosen speed, thereby providing a compared speed,

and, optionally,

- adjusting the first chosen speed in accordance with the compared speed. As described above, this method may be used for calculating the first chosen speed in order to provide the desired second chosen speed and/or for calibrating the first chosen speed in order to provide the desired second chosen speed.

The invention will be further elucidated with reference to figures shown in a drawing, in which:

Figures 1A - ID schematically show a system, comprising a plurality of cover systems for windows and a door according to an embodiment of the invention;

Figure 2 is a diagram of the velocity/RPM versus travel length of the free end of a cover element.

Figures 1A - ID show two windows 1, 2 and a door 11 of a building. A first window 1 has a ventilation area 3 near its upper end. The second window 2 and the door 11 do not have such a ventilation area. A roller blind 4 of the first window 1 is therefore located lower than a roller blind 5 of the second window 2 and the door 11. The door 11 is longer than the two windows 1 ,2, such that the roller blind 13 of the door 11 is able to travel further downwards. The roller blinds 4, 5, 13 are wounded to rotatable elements 7, 8, 12, respectively, which are rotatable in a first direction for winding up said roller blind 4, 5, 13 and in a second, opposite direction for unwinding and thereby lowering said roller blind 4, 5, 14. Said rotatable elements 7, 8, 12 are rotatably drivable by respective motors (not shown). In accordance with the invention, each cover system comprises a (micro)processor configured for controlling their respective motor in such a way that said rotatable element 7, 8, 12 is rotated with a first chosen speed such that a free end 9, 10, 14 of the roller blind 4, 5, 13 is transported at a second chosen speed. This way, the traveling speed of the free end 9, 10, 14 of the roller blind 4, 5, 13 may be chosen as desired. In this system shown in figures 1A - ID, because the roller blind 5 of the second window is located higher, the motors of rotatable elements 8, 12 are first and only activated, such that only the free ends 10, 14 of the cover blinds 5, 13 start traveling in a vertical downward direction, see figure IB. As soon as the free ends 10, 14 are at or near the height of the roller blind 4, the motor of rotatable element 7 is also activated, such that also the free end 9 of the cover blind 4 starts traveling in the vertical downward direction. The microprocessors are hereby configured to control the motors such that the free ends 9, 10, 14 travel at the same height and with the same speed, see figure 1C. When the roller blinds 4, 5 are at their lower end position, the motors of rotatable elements 7, 8 stop rotation thereof, such that the free ends 9, 10 of the roller blinds 4, 5 are maintained in their end position. The free end 14 of roller blind 13 continues traveling downwards until it is also in its end position near the lower end of the door 11. If the roller blinds 4, 5, 13 are transported in a reverse, upward direction, the roller blind 13 will start traveling first, and the roller blinds 4, 5 will start traveling as soon as the free end 14 of roller blind 13 is at or near the position of the free ends 9, 10 of roller blinds 4, 5. The roller blind 4 will stop at its start position and the roller blinds 5, 13 will continue traveling until they are also at their start position.

It is noted that instead of a roller blind the invention may relate to any cover system comprising any cover element, for example, but not limited thereto, a (roller) blind, a (roller) shade, a (roller) shutter, or the like. Such a cover element may be wounded to the rotatable element, or the cover element may comprise means for retracting and extending that are wounded to the rotatable element.

Figures 1 A - ID show a system comprising three cover systems according to the invention. The invention is however also applicable to single cover systems, for example to provide a constant traveling speed of the free end of the cover element. This is further explained with respect to figure 2.

Figure 2 is a diagram of the velocity of the free end of the cover element and rotational speed (RPM) of the rotatable element versus travel length of the free end of a cover element. Both the RPM profile 20 of the rotatable element (first chosen speed) and the velocity profile 25 of the free end of the cover element (second chosen speed) are shown. The first chosen speed is hereby a rotational speed, or RPM, and the second chosen speed is a translational speed, for example in m/s.

In accordance with the invention it is desired to be able to control the velocity profile 25 of the free end of the cover element, since this is the traveling speed that is clearly visible for users of a building and for inward direction viewers from the outside of the building. The velocity profile 25 of the free end is normally chosen to be constant, but other non-constant velocity profiles are possible as well. Based on a desired and chosen velocity profile 25, it will be calculated with which rotational speed the rotatable element must rotate to realise the required velocity profile 25 accurately.

For example, at a start position of the cover element the windings on the rotatable element are all wounded around the rotatable element and thus relatively thick, such that at a certain rotational speed of the rotatable element the free end of the cover element travels faster than at a near end position of the cover element at the same rotational speed of the rotatable element, when there are fewer windings on the rotatable element compared to the start position. In order to have the constant velocity profile 25 of the free end of the cover blind, the rotational speed of the rotatable element must thus be relatively low near the start position of the cover blind and higher near the end position of the cover blind.

As is shown in figure 2, at starting or stopping transportation of the free end of the cover element the transportation speed may be gradually increased or decreased, i.e. a so called slow start or slow stop. This is obtained by gradually increasing or decreasing the rotational speed of the rotatable element. The slow start or slow stop at the start position of the cover is indicated by 21, 26 for the rotatable element and free end respectively, at the end position by 22, 27, and at an intermediate stop position by, 23, 24, 28, and 29.

For one cover system the invention provides a system for providing a desired traveling speed of the free end of the cover. For a system of cover systems, such as the system shown in figures 1A - 1C, the velocity profiles of each cover system as shown in figure 2 may be matched, such that all free ends travel with the same transportation speed and/or at the same height. The various microprocessors may communicate with each other to match the velocity profiles and/or the height of the free ends.

It is also possible to independently control the various cover systems of a system of cover systems. For example, if a user wants to activate only one cover of a system of covers, it is possible to only activate this cover. If multiple covers are activated, the various microprocessors may communicate with each other to match the velocity profiles and/or heights of the free ends.

The rotational speed required for the desired speed of the free end of the cover may be calculated in various ways. For example, it is possible to calculate this speed based on at least one, or a plurality of parameters as described with respect to claim 2 and/or 3. Alternatively or additionally, the rotational speed may be calculated based on a measured speed, as described with respect to claim 6. The measured or calculated speed may be used for calibration of the system.

It is noted that the invention is not limited to the shown embodiments but also extends to variants within the scope of the appended claims.