Detection of the position of a winding drum coupled to a motor via a damping flexible element

Patent metadata

Field	Value
Publication number	US-2016124418-A1
Application number	US-201414896302-A
Country	US
Kind code	A1
Filing date	Jun 6, 2014
Priority date	Jun 6, 2013
Publication date	May 5, 2016
Grant date	—

Abstract

An apparatus ( 10 ) for winding a screen ( 12 ) comprises a winding drum ( 14 ) for winding the screen ( 12 ) which can rotate about an axis of rotation ( 16 ) with respect to a fixed frame of reference over more than one revolution between at least one first end-of-travel position and a second end-of-travel position, a motor assembly ( 30 ) comprising a motor ( 32 ) equipped with a stator ( 32.1 ) intended to be fixed to a fixed support ( 23, 26 ) and a rotor ( 32.2 ) kinematically connected to the winding drum ( 14 ). A first measurement assembly ( 51 ) comprises a first encoder ( 46 ) secured to the rotor ( 32.2 ), a first sensor for reading the first encoder ( 46 ) and generating a first counting signal when the first encoder ( 46 ) turns. First processing means ( 50 ) generate, as a function of the first counting signal, a first signal indicative of the position of the screen, which signal is monotonous when the drum moves from the first end-of-travel position to the second end-of-travel position. A second measurement assembly ( 64 ) makes it possible to detect at least one indexed position of the drum ( 14 ) per revolution of the drum in the fixed frame of reference. A calibration memory ( 56 ) stores at least one first calibration value for the first signal indicative of the position of the screen in the indexed position of the drum and at least one first quantitative algebraic comparison between a current value of the first signal indicative of the position of the screen as measured on passing through the indexed position during an observation phase and the first calibration value is delivered.

First claim

1 . A winding device for a screen, including
a winding drum for winding the screen, which can rotate around an axis of rotation with respect to a stationary frame of reference over more than one revolution between at least one first end-of-travel position and a second end-of-travel position; a motor assembly comprising a motor equipped with a stator intended to be fixed to a stationary support and a rotor kinematically connected to the winding drum; a first measurement assembly comprising a first encoder secured to the rotor, a first sensor for reading the first encoder and generating a first counting signal when the first encoder turns; and first processing means generating, as a function of the first counting signal, a first signal indicative of the position of the screen, the first signal being monotonic when the drum moves from the first end-of-travel position to the second end-of-travel position; a second measurement assembly for detecting at least one indexed position of the drum per revolution of the drum in the fixed frame of reference, a calibration memory for storing at least one first calibration value for the first signal indicative of the position of the screen in the indexed position of the drum; and a comparator for delivering at least one first quantitative algebraic comparison between a current value of the first signal indicative of the position of the screen as measured on passing through the indexed position during an observation phase and the first calibration value.

2 . The device according to claim 1 , wherein the second measuring assembly includes a second encoder secured to the drum, a second stationary sensor in the stationary frame of reference to read the second encoder, and second processing means to generate a second signal representative of a passage by the indexed position when the second encoder rotates with the drum.

3 . The device according to claim 2 , wherein the second encoder has no more than eight singularities, and preferably one singularity, readable by the second sensor upon each drum revolution.

4 . The device according to claim 2 , wherein the drum is guided relative to the stationary support by means of at least one guide bearing, the second encoder being positioned on a rotating part of the bearing.

5 . The device according to claim 1 , wherein the motor assembly includes at least one reduction gear between the rotor and the drum.

6 . The device according to claim 1 , wherein the device includes at least one rotary vibration damper positioned between the rotor and the drum.

7 . The device according to claim 1 , wherein the device includes at least one stationary vibration damper positioned between the stator and the stationary support.

8 . The device according to claim 1 , wherein the motor assembly includes a casing housed in a tube mounted stationary on the stationary support.

9 . The device according to claim 1 , wherein the second measuring assembly comprises a bipolar sensor and the second encoder determines a change in polarity.

10 . The device according to claim 1 , wherein the comparator includes means for generating an offset value depending on at least the first algebraic comparison.

11 . The device according to claim 10 , wherein it further includes a controller for controlling the motor in a subsequent phase based on at least a current value of the first signal indicative of the position of the screen measured in the subsequent phase and the shift value.

12 . The device according to claim 10 , wherein the comparator generates the shift value as a function of several algebraic comparisons between several current values of the first signal indicative of the position of the screen measured upon passage by the indexed position in an observation phase and several calibration values stored in the calibration memory.

13 . A method for controlling a device for winding a screen, including a winding drum of the screen, driven by a rotor of a motor, the method comprising:
in a calibration phase, at least one calibration value of a rotation angle corresponding to an indexed position of the drum is stored; in an observation phase, the drum is rotated using the motor while measuring a current value of the rotation angle of the rotor of the motor and detecting the passage of the drum by the indexed position, and at least one quantitative comparison is done between the current value when the drum passes by the indexed position and the calibration value.

14 . The method according to claim 13 , wherein in the calibration phase, the drum is driven with the motor between a first end-of-travel position and a second end-of-travel position in a reference rotation direction and as many calibrations are stored as there are passages of the drum by the indexed position.

15 . The method according to claim 14 , wherein in the observation phase, the drum is rotated in the reference direction, and as many quantitative comparisons are done between the current value when the drum passes by the indexed position and the calibration value as there are passages of the drum by the indexed position.

16 . The method according to claim 15 , wherein a shift value is determined over one revolution or more than one revolution of the drum, based on several of said comparisons.

17 . The method according to claim 13 , wherein a new position value of the motor is determined upon each passage by an indexed position as a function of the current value of the first signal indicative of the measured position of screen and the shift value determined in the observation phase for one or more indexed positions.

Assignees

• Somfy Sas

Inventors

• Lagarde Eric
• Georgeault Ronan
• Montéremand Laurent
• Blanc Serge
• Ramos Joël

Classifications

• G05B19/404 Primary

  characterised by control arrangements for compensation, e.g. for backlash, overshoot, tool offset, tool wear, temperature, machine construction errors, load, inertia (G05B19/19, G05B19/41 take precedence) · CPC title

• E06B2009/6872

  using counters to determine shutter position · CPC title

• E06B2009/6845

  sensing position · CPC title

• E06B2009/6809

  Control · CPC title

• E06B9/72 Primary

  comprising an electric motor positioned inside the roller · CPC title