METHOD FOR CONTROLLING A MOTORIZED BLINDING INSTALLATION

Abstract

The invention relates to a method for controlling a tubular motor driving a winding tube of a blind fabric fixed to a load bar guided by two unfolding arms, the method comprising an adjustment phase (E0) including: - during the deployment of the fabric, detection (E02) of an increase in speed or motor torque, resulting from an unfolding movement of the arms preceding their arrival in a locking position and automatic stop of the deployment (E03) in response to said detection; - memorization (E04) of the position of the blind at rest as the lower limit position; - continuous retraction (E05) of the blind to the upper limit position; the method including during subsequent operating cycles: - during the deployment of the fabric, an automatic stop step of the deployment at the position memorized during the adjustment phase.

Description

1 Method for controlling a motorized blind installation The present invention relates to the field of motorized mobile screens, in particular for solar protection, of the blind type and in particular awning, or equivalent, intended to equip the bays of a building.It relates more specifically to a method for controlling a motorized blind installation. The installation comprises a frame supporting a roller tube capable of being rotated by an actuator including a tubular motor. This allows a blind fabric to be wound or unwound around the tube at one end. The blind fabric is attached at the other end to a weight bar positioned substantially parallel to the roller tube and mounted to move relative to the frame between end positions of the fabric wound and unwound, respectively, by means of retractable arms. The method includes, during the unwinding of the fabric, a step of controlling the actuator to bring the fabric to a fully unwound, taut end position. When the blind is retracted, the entire fabric is wound, the arms are retracted, and the weight bar comes into contact with the blind frame.During deployment, the motor rotates the roller tube, and the guide arms gradually extend to a locking position, corresponding to the fully extended end position of the fabric, in which it is taut. Typically, the tubular actuator that rotates the roller tube to position the blind in its extended or retracted end positions is coupled with a limit switch that stops the actuator when the blind is fully extended or retracted. Such a device generally includes a mechanism for counting the windings of the fabric around the roller tube to determine the end positions. Thus, the counting device associated with the actuator allows the current position of the load bar to be known at all times, and during an adjustment phase, the two end-travel positions, rolled up and unrolled, are memorized. To do this, the user maneuvers the blind in small steps in both directions of rotation until the desired ideal end-travel positions are reached and memorized. In subsequent operating cycles, the actuator is commanded to stop automatically at the memorized end-travel positions. A particular constraint is placed on determining the unrolled end-travel position of the blind, which must be set precisely to guarantee optimal tension of the unrolled fabric. Indeed, in this fully extended position of the blind, it is necessary that the fabric be taut, both for aesthetic and technical reasons (preventing water accumulation in case of rain,(more rigid support and therefore wind resistance, etc.). However, it appears that such precision is difficult to achieve given the variations in fabric length observed over time. Thus, during the use of the awning, the fabric may stretch slightly, which will result in a slack fabric effect in the fully extended end position. Motorized awning installation control devices are already known that allow the awning to be safely placed in a taut fabric position at the end of its extension. For example, document FR 2 899 923 describes a method for controlling an awning installation based on detecting the drop in fabric tension when the unfolding fabric guide arms are in a fully extended position, followed by a slight winding movement of the fabric onto the tube in response to the detection of this drop in fabric tension.This winding stage is automatically stopped before a perceptible retraction of the arms. Triggering the winding stage as soon as the fabric tension drops allows the fabric to be automatically retensioned, without the need for counting devices to control the stopping of the fabric's deployment. However, this method of controlling the blind to bring the fabric to a fully extended, taut end-of-travel position is relatively complex to implement, as it requires a slight retraction movement of the blind to retension the fabric. Document FR 2 816 465 describes a method for controlling a blind based on determining a maximum torque value applied to the motor at the end of the blind's extension travel. This value corresponds to an extension threshold value at which the blind occupies a fully extended, taut end-of-travel position.Then, the torque exerted on the motor during deployment is detected, and if the unwinding threshold value is exceeded, the motor is stopped during unwinding and retracted until the detected torque value again exceeds the unwinding threshold value. This control method therefore also involves a retraction movement of the fabric after the motor stops to ensure that the blind is in a taut, fully extended position at the end of its travel. Therefore, one objective of the invention is to provide a method for controlling a motorized blind system that allows the fabric to be placed in a taut position at the end of its travel in a simple and reproducible manner. To this end, the invention relates to a method for controlling a motorized blind system.the installation comprising a frame supporting a winding tube capable of being driven in rotation by an actuator 15 comprising a tubular drive motor enabling a blind fabric to be wound or unwound around the tube by a first end, the blind fabric being fixed by a second end to a load bar disposed substantially parallel to the winding tube and mounted movable relative to the frame between end-of-stroke positions respectively 20 wound and unwound by means of folding arms, the method comprising, during the unwinding of the fabric, a step of controlling the actuator suitable for bringing the fabric to an unwound and taut end-of-stroke position, the method being characterized in that it comprises an adjustment phase comprising: 25 - during the unwinding of the fabric, a step of monitoring the rotational speed of the motor or the motor torque,- a step for detecting an increase in motor speed or motor torque, resulting from an unfolding movement of the arms at the end of deployment, preceding the arms reaching a locked position (30° arm lock), with deployment stopping automatically in response to the detection of the increased motor speed or motor torque; 3039846 4 - a step for memorizing the blind's position when deployment stops, the memorized position corresponding to the fully extended, taut end-of-stroke position; - a step for continuously retracting the blind to the fully retracted end-of-stroke position (5° rolled up); the method comprising, during subsequent operating cycles: - during fabric deployment, a step for automatically stopping deployment at the position memorized during the adjustment phase. Advantageously, the adjustment phase is repeated periodically. Preferably, the adjustment phase,Excluding the step of continuously retracting the blind to the fully retracted end-of-travel position, this is repeated periodically or at each operating cycle. Advantageously, during the adjustment phase, monitoring the motor speed or motor torque consists of continuously measuring the motor speed or motor torque and evaluating the rate of change in the motor speed or motor torque.The automatic stopping of the blind deployment in response to the detection of an increase in motor rotation speed or motor torque is triggered when said speed of variation increases within a given time interval 20. The invention also relates to a motorized blind installation comprising a frame supporting a winding tube capable of being driven in rotation by an actuator comprising a tubular drive motor allowing a blind fabric to be wound or unwound around the tube by 25 at one end, the blind fabric being fixed at a second end to a load bar arranged substantially parallel to the winding tube and mounted movable relative to the frame between end-of-travel positions respectively wound and unwound by means of folding arms,said installation being characterized in that it comprises a speed or torque sensor for measuring the motor's rotational speed or torque and a control unit capable of controlling the actuator and implementing the control method according to the invention. Other features and advantages of the invention will become clear from the following description, which is provided by way of example and not limitation, with reference to the accompanying drawings, in which: - Figure 1 is a schematic illustration of a motorized blind installation; - Figure 2 is a timing diagram showing, as a function of time, the evolution of the motor's rotational speed in Figure 1 during a full deployment of the blind fabric, according to different phases of deployment; - Figure 3 is a flowchart of one execution method of the control method according to the invention. With reference to Figure 1,A motorized awning installation 1 according to the invention is a retractable awning type installation, typically used for sun protection of terraces. A roller tube 3 is fixed to a frame 2, intended to be fixed 15 to a structure such as a building facade. A fabric 4 is wound onto this tube at one end. The other end of the fabric 4 is fixed to a front bar 5, which is held to the frame 2 by at least two folding arms 6, 7. These arms guide the front bar 5 and maintain the tension of the fabric 4 during the rolling and unrolling operations. The arms 6, 7 are fixed on one side to the frame and on the other side to the front bar and have at least one articulated elbow allowing them to bend or unfold to accompany the folding or unfolding movement of the fabric. The arms are equipped,generally at the elbow of a spring (not shown) 25 which is stressed during the winding of the fabric. An actuator comprising a tubular motor 8 is mounted inside the winding tube 3. This actuator is capable of driving the tube 3 in rotation in a first direction and, alternately, in a second opposite direction, so as to allow the fabric 4 to be wound or unwound. In accordance with the invention, the actuator also includes a speed sensor capable of measuring the rotational speed of the motor. As will be seen in more detail later, it is the variations in this quantity that will allow the control of the installation 1 during an adjustment phase aimed at determining the unwound end position of the fabric. However, since the motor is driven by the force exerted by the arms, a measurement of the torque received by the motor during the deployment phase can be used equivalently. Also,A sensor for measuring motor torque during deployment may be used while remaining within the scope of clause 5 of the invention. Finally, the actuator is controlled via a control unit capable of executing the control method described with reference to Figure 3. This control unit typically consists of a programmable computer associated with a data storage medium containing instructions for executing the method. When the blind is retracted, the entire fabric 4 is wound around the roller tube 3, the arms 6, 7 are folded, and the bottom rail 5 comes into contact with the blind housing or support (not shown). Typically, during deployment, the tubular motor 8 rotates the tube 15 3 to unroll the fabric 4. The arms 6, 7 then gradually extend to their maximum length, corresponding to a locking position of the arms.in which the arms are braced, ensuring good fabric tension. In existing installations, this position also corresponds to the fully extended end-of-travel position, or the fully deployed position, also known as the "low end-of-travel position." Figure 2 illustrates the variation in motor rotation speed measured by the sensor over time at different phases of blind deployment. Thus, during blind deployment from the fully retracted end-of-travel position, a phase of progressive arm unfolding allows the blind to be unfurled with the fabric taut thanks to the action of the springs integrated into each arm. In this phase, labeled V1 in Figure 2, where the arms are opening and not locked, the measured motor rotation speed is almost constant. Then,When the arms reach the end of their 30-degree unfolding but before reaching their locking position, the fabric remains taut, and a significant increase in the motor's rotational speed is detected by the sensor until the arms reach their locking position. This deployment phase, referenced V2 in Figure 2, where the motor's rotational speed is accelerating, is caused by the kinematics of the arms during deployment. Indeed, at the end of deployment, when the fabric reaches its fully extended position, for a short period of time, the force exerted by the arms just before reaching their locking position is much greater, which results in a significant increase in the motor's rotational speed. Then, when the arms reach their locking position, a third phase, referenced V3 in Figure 2, occurs, in which the motor is no longer driven.so that it slows down by slightly unwinding the slack fabric, resulting in a measured motor speed of deceleration, in position 10, since the fabric no longer exerts stress on the winding tube and therefore on the actuator. Thus, the fabric remains taut until the arms reach the locking position and is then slack if the motor continues to drive the rotating tube. Also, according to the invention, the position in which an increase in motor speed is detected, resulting from an unfolding movement of the arms at the end of their deployment preceding the arms reaching their locking position,corresponds to the ideal fully extended, tensioned end-of-travel position. Determining this fully extended, tensioned end-of-travel position (lower limit switch) is therefore based on detecting the acceleration of the motor's rotational speed during blind deployment. The motor is automatically stopped, and thus the roller tube is locked, as soon as the increase in motor rotational speed is detected. This brings the system to a halt, preventing the actuator from continuing to extend the fabric, which therefore remains advantageously tensioned in its lower limit switch position. Based on this principle, an execution method for the process will now be described with reference to the flowchart in Figure 3. The determination of the fully extended, tensioned end-of-travel position is carried out during an adjustment phase of the system. This adjustment phase is activated, for example, by the installer during an initial adjustment phase.by means of transmitting an appropriate command to the actuator, for example from a wired or wireless control point. When entry into the adjustment phase is activated, the following steps are implemented. Switching to the adjustment phase triggers an E01 deployment step of the blind 3039846 8 from the rolled-up limit switch position (upper limit switch), during which the motor's rotational speed, continuously measured by the sensor, is monitored during deployment. During an E02 step, the arms reach the end of their opening but are not yet locked, i.e., they have not yet reached their locking position. Shortly before the arms reach their locking position, the actuator control unit detects an increase in the motor's rotational speed as measured by the sensor. To do this, the control unit evaluates the rate of change in the motor's rotational speed during the deployment.and detects when the speed of variation increases within a given, relatively short time interval. In response to the detection of the increase in the motor's rotational speed at the end of deployment, the control unit, in step E03, immediately commands the motor to stop, the blind then being considered, according to the invention, to be in a position corresponding to the ideal fully extended, tensioned end-of-travel position. Following this stop, in step E04, the control unit memorizes the position of the blind at the time of the deployment stop, for example via the position provided by the counting device; the position thus memorized corresponds to the fully extended, tensioned end-of-travel position that will be used during subsequent operating cycles. Then,The adjustment phase ends with step E05, in which the control unit triggers the continuous retraction of the blind (without stopping) to the fully retracted end position. The adjustment phase then ends, and the blind is operational for subsequent operating cycles, in which steps E1 to E13 are executed. Thus, when switching to a normal operating cycle (step E1), the control unit, in step E11, commands the blind to extend. Then, in step E12, when the blind reaches the position previously memorized in the adjustment phase, the control unit, in step E13, commands the automatic stopping of the extension in this memorized position, corresponding to the fully extended end position. During use, the fabric may stretch slightly.This can result in a slack fabric effect at the end of the extended travel position (3039846 9). The control unit is then designed to automatically readjust the extended end position periodically or at each operating cycle by re-executing steps E01 to E04 of the adjustment phase, transparently to the user. In other words, in cases where the detection of the extended end position occurs periodically or at each operating cycle, i.e., when the user commands the blind to extend, the adjustment phase can be executed again, but excluding step E05, which involves continuously retracting the blind to the retracted end position. Indeed, the blind must extend, detect the extended end position according to the principles described in steps E01 and E02,The motor will automatically stop at this position and this new position will be memorized, replacing the previous one. The blind should not then automatically retract according to step E05 of the adjustment phase, as this is not the user's desired behavior in this case.

Claims

DEMANDS 1. Method for controlling a motorized blind installation (1), an installation comprising a frame (2) supporting a winding tube (3) capable of being driven in rotation by an actuator comprising a tubular drive motor (8) enabling a blind fabric (4) to be wound or unwound around the tube at one end, the blind fabric (4) being fixed at a second end to a load bar (5) disposed substantially parallel to the winding tube (3) and mounted to move relative to the frame (2) between end-of-travel positions of the fabric wound and unwound respectively by means of folding arms (6, 7), the method comprising, during the unwinding of the fabric, a step of controlling the actuator to bring the fabric to an unwound, taut end-of-travel position, the method being characterized in that it comprises an adjustment phase (E0) comprising: - during the deployment of the canvas, a step (E01) of monitoring the motor's rotation speed or motor torque, - a step (E02) of detecting an increase in the rotational speed of the motor or the motor torque, following an unfolding movement of the arms at the end of deployment preceding the arrival of the arms in a locking position of the arms, the stop of the deployment being triggered automatically (E03) in response to the detection of the increase in the rotational speed of the motor or the motor torque; - a step (E04) of memorizing the position of the blind when the deployment is stopped, the memorized position corresponding to the extended, taut end-of-travel position; - a step (E05) of continuous folding of the blind until the rolled-up end-of-travel position; the process comprising the following operating cycles: - during the deployment of the canvas, an automatic stop step (El3) of the deployment at the position memorized during the adjustment phase.

2. Method according to claim 1, characterized in that the adjustment phase (E0) is repeated periodically.

3. Method according to claim 1 or 2, characterized in that the adjustment phase (E0), excluding the step (E05) of continuous folding of the blind to the rolled-up end position, is repeated periodically or at each operating cycle.

4. A method according to any one of the preceding claims, characterized in that during the adjustment phase, monitoring the motor speed or motor torque consists of continuously measuring the motor speed or motor torque and evaluating a rate of change of the motor speed or motor torque, the automatic stopping of the blind deployment in response to the detection of an increase in motor speed or motor torque being triggered when said rate of change increases within a given time interval.

5. Motorized blind installation (1) comprising a frame (2) supporting a winding tube (3) capable of being driven in rotation by an actuator comprising a tubular drive motor (8) enabling a blind fabric (4) to be wound or unwound around the tube by a first end, the blind fabric being fixed by a second end to a load bar (5) disposed substantially parallel to the winding tube and mounted movable relative to the frame between end-of-travel positions respectively wound and unwound of the fabric by means of folding arms (6, 7), said installation being characterized in that it comprises a speed or torque sensor intended to measure the rotational speed of the motor or the motor torque and a control unit adapted to control the actuator and to implement the control method according to any one of the preceding claims.

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