DUAL CONTROL OF THE ANGULAR POSITION OF A GEARMOTOR SHAFT

Abstract

The invention relates to a method for controlling the angular position (100) of a motor vehicle, comprising a step (109) for controlling the angular position of a geared motor (x(t)), which includes: a determination (105) of the angular position of the geared motor (x(t) = Sp(t0) + K*Yr(t)) from a detection of the angular position of the motor shaft by a motor shaft angular position sensor, and / or a determination (113) of the angular position of the geared motor (x(t) = Sp(t)) from a detection of the angular position of a moving element by a moving element angular position sensor. (See Figure 4 for the abbreviated version.)

Description

Title of the invention: DOUBLE CONTROL OF THE ANGULAR POSITION OF A GEARED MOTOR SHAFT TECHNICAL FIELD OF THE INVENTION

[0001] The invention relates to a control of the angular position of a geared motor shaft.

[0002] It relates in particular to a double control of the angular position of a geared motor output element of a cooling system valve for a motor vehicle. STATE OF THE ART

[0003] A geared motor for a motor vehicle generally comprises an electric motor and a reducer which are housed in a housing. The geared motor also comprises an angular position detector of the electric motor which is housed in the housing. This angular position detector is configured to detect the angular position of the motor, in particular by determining the position of an output shaft of the geared motor.

[0004] An angular position sensor typically includes a Hall effect sensor that measures the angular position of the electric motor shaft, providing a reliable but inaccurate measurement of the angular position of the gearmotor output shaft.

[0005] Another type of angle sensor is an electric motor rotor revolution counter. The revolution counter measures the back electromotive force generated by the currents induced in the coils of the electric motor, to determine the number of revolutions of the electric motor rotor.

[0006] The rev counter does not allow for the detection of a failure in the drive of the output shaft and / or the output gear of the geared motor. It also needs to be calibrated regularly, for example each time the electric motor is started or each time the power supply is cut. It therefore does not provide a sufficiently robust measurement of angular position, despite its greater accuracy than a Hall effect sensor.

[0007] There is a need to accurately determine the angular position of a geared motor output shaft, while having available a robust measurement of the geared motor output shaft position, and while having sensors that are easy to manufacture, install, and use. Statement of the invention

[0008] The present invention aims to remedy all or part of the drawbacks of the state of the technique cited above.

[0009] In this regard, the invention relates to a system for controlling the angular position of a geared motor for a motor vehicle. According to the invention, the control system comprises a motor shaft angular position sensor and a movable element angular position sensor. The motor shaft angular position sensor is configured to detect the angular position of an electric motor shaft of the geared motor, from the determination of the position of the rotor of the electric motor. The movable element angular position sensor is configured to detect the angular position of a movable element of the gear reducer of the geared motor. The movable element is a gear reducer shaft or a gear reducer transmission element.

[0010] By means of the invention as claimed, the angular position of a geared motor, in particular of a geared motor output element, can be known precisely, while having a robust measurement of the position of the geared motor, and while having a control system that is easy to manufacture, install and use.

[0011] In particular, the manufacture of the control system and the use of the control system are facilitated by dispensing with a precise and / or difficult to assemble sensor. It is in particular possible to precisely determine the angular position of the electric motor shaft and that of the output element of the geared motor, during normal operation of the geared motor angular position control system. The angular position of the electric motor shaft and the angular position of the output element of the geared motor are known reliably, in particular regardless of the conditions of use of the geared motor.

[0012] According to a particular embodiment, the motor shaft angular position sensor is a revolution counter which is configured to detect the angular position of an electric motor shaft of the geared motor from the determination of the position of a rotor of the electric motor.

[0013] Preferably, the determination of the position of the rotor of the electric motor is carried out from the evaluation of a counter electromotive force which is generated by currents induced in non-excited coils of the electric motor.

[0014] According to a particular embodiment, the moving element angular position sensor is a Hall effect sensor.

[0015] Preferably, the Hall effect sensor is assembled to a printed circuit of an electronic card of the control system. Preferably, the Hall effect sensor is located outside a geared motor shaft and at a distance from the moving element.

[0016] According to a particular embodiment, the control system comprises a control unit which is configured to determine the angular position of the geared motor from the detection of the angular position of the motor shaft by the angular position sensor of the motor shaft.

[0017] According to a particular embodiment, the control unit is configured to determine the angular position of the geared motor from the detection of the angular position of the mobile element by the mobile element angular position sensor.

[0018] Preferably, the control system is configured to control the angular position of an output element of the geared motor, the output element of the geared motor being an output gear or an output shaft of the geared motor.

[0019] Preferably, the movable element is the output element of the geared motor.

[0020] The invention also relates to a geared motor for a motorized vehicle comprising a control system as described above.

[0021] According to a particular embodiment, the motor is a permanent magnet synchronous electric motor for a fluid circulation system of a motorized vehicle.

[0022] According to a particular embodiment, the geared motor is a geared motor of a fluid circulation valve for a motorized vehicle.

[0023] Preferably, the geared motor is a geared motor of a liquid circulation valve of a cooling system for a motor vehicle.

[0024] The invention also relates to a method for controlling the angular position of a motorized vehicle. The control method comprises a step of controlling the angular position of the geared motor by an angular position control system as defined above. The step of controlling the angular position of the geared motor comprises a determination of the angular position of the geared motor from the detection of the angular position of the motor shaft by the motor shaft angular position sensor. In addition or as a variant, the step of controlling the angular position of the geared motor comprises a determination of the angular position of the geared motor from a detection of the angular position of the movable element by the movable element angular position sensor.

[0025] According to a particular embodiment, the control method comprises a determination of the angular position of the output element of the geared motor from the detection of the angular position of the motor shaft, when a representative value of the detected current angular position of the motor shaft is greater than the difference between a representative target value of the angular position of the motor shaft and a sensor tolerance, and the representative value of the detected current angular position of the motor shaft is less than a sum of the representative target value of the angular position of the motor shaft and a sensor tolerance. The representative value of the detected current angular position of the motor shaft is representative of a current angular position detected by the motor shaft angular position sensor.

[0026] According to a particular embodiment, the control method comprises a verification whether a value representative of the current detected angular position of the shaft of motor is greater than a difference between a detected current angular position representative value of the movable element and the sensor tolerance. The control method comprises checking whether the detected current angular position representative value of the motor shaft is less than a sum of the detected current angular position representative value of the movable element and the sensor tolerance. The detected current angular position representative value of the movable element is representative of a current angular position detected by the movable element angular position sensor.

[0027] According to a particular embodiment, the control method comprises a change in angular position of the electric motor, when a detected current angular position representative value of the motor shaft is greater than the difference between the detected current angular position representative value of the movable element and the sensor tolerance, and the detected current angular position representative value of the motor shaft is less than a sum of the detected current angular position representative value of the movable element and the sensor tolerance. The change in angular position of the electric motor takes place if the detected current angular position representative value of the motor shaft is far from the target angular position representative value of the motor shaft beyond the sensor tolerance.

[0028] According to a particular embodiment, the control method comprises a determination of the angular position of the geared motor from the detection of the angular position of the mobile element by the mobile element angular position sensor, in the event of failure to determine the angular position of the geared motor from the detection of the angular position of the motor shaft by the control system.

[0029] Preferably, the control method identifies a failure to determine the angular position of the geared motor from the detection of the angular position of the motor shaft, when a number of attempts to determine the angular position of the geared motor from the detection of the angular position of the motor shaft is greater than a threshold value of attempts.

[0030] Preferably, the control method identifies a failure to determine the angular position of the geared motor from the detection of the angular position of the motor shaft, when a duration of determination of the angular position of the geared motor from the detection of the angular position of the motor shaft is greater than a threshold duration.

[0031] According to a particular embodiment, the control method comprises determining an angular position of the geared motor from the detection of the angular position of the movable element, when a detected angular position of the movable element is greater than the difference between a target value of angular position of the element mobile element and a sensor tolerance, and that the current detected angular position of the mobile element is less than a sum of the target value of the angular position of the mobile element and a sensor tolerance.

[0032] According to a particular embodiment, the control method comprises an initialization step which comprises a calibration of the motor shaft angular position sensor each time the electric motor is started and / or each time the electrical power supply to the electric motor is cut off.

[0033] According to a particular embodiment, the initialization step comprises at least one detection of the angular position of the mobile element by the mobile element angular position sensor. BRIEF DESCRIPTION OF THE FIGURES

[0034] Other advantages, aims and particular characteristics of the present invention will emerge from the following non-limiting description of at least one particular embodiment of the devices and methods which are the subject of the present invention, with reference to the appended drawings, in which: - [Fig.l] [Fig.l] is a schematic perspective representation of a fluid circulation system valve reducer motor for a motor vehicle; - [Fig.2] [Fig.2] is an exploded perspective view of the geared motor according to the first embodiment; - [Fig.3] [Fig.3] is a partial schematic view of the electric motor and an angular position control system of the geared motor according to the first embodiment; - [Fig.4] [Fig.4] illustrates the implementation of a method for controlling the angular position of a geared motor, according to the first embodiment of the invention; - [Fig.5] [Fig.5] illustrates an initialization phase of the method for controlling the angular position of a geared motor, according to the first embodiment; - [Fig.6] [Fig.6] illustrates the implementation of a method for controlling the angular position of a geared motor, according to a second embodiment of the invention. DETAILED DESCRIPTION OF THE INVENTION

[0035] The present description is given as a non-limiting example of embodiment.

[0036] [Fig.l] represents a geared motor 2 of a fluid circulation valve 1 for a motor vehicle. The geared motor 2 is preferably a geared motor of a coolant circulation valve 1 for a motor vehicle. The geared motor 2 is configured to open and / or close at least one distributor shutter of the valve 1.

[0037] With reference to Figures 1 and 2, the geared motor 2 comprises a casing, an electric motor 4, a reducer 6 and a control system 8. The casing comprises a housing 3 and a cover 5. It houses the electric motor 4, the reducer 6 and the control system 8.

[0038] The electric motor 4 comprises a rotor 14 and a stator 20. The electric motor 4 is configured to drive the reducer 6 which is mechanically connected to at least one distributor of the valve 1. The electric motor 4 is for example a permanent magnet synchronous motor, which is also known as a brushless motor. The rotor 14 comprises for example magnets 16 of opposite polarities and a motor shaft 18 which is the output shaft of the electric motor 4. The rotor 14 is movable relative to the stator 20. The stator 20 comprises for example coils 22 which are energized sequentially to rotate the rotor 14.

[0039] The reducer 6 comprises shafts 30 and transmission elements 32. The reducer 6 is generally configured to reduce the output rotation speed of the geared motor 2 and to increase the output torque of the geared motor 2, relative to the output rotation speed and torque of the electric motor 4. The reducer shafts 30 may or may not be movable. The shafts 30 may be parallel, intersecting or orthogonal in pairs. Preferably, the reducer 6 has cylindrical or epicyclic gears and the shafts 30 are parallel to each other. The transmission elements 32 are generally toothed wheels. The reducer 6 comprises an output element which forms the output of the reducer 6. The output element is for example an output shaft 35 or an output transmission element 37. The output element 35, 37 is in particular configured to mechanically engage the shutter of the valve 1.

[0040] With joint reference to Figures 2 and 3, the control system 8 comprises a sensor 40 for the angular position of the motor shaft 18, a sensor 42 for the angular position of a mobile element, and a control unit. The control system 8 takes the form of at least one electronic card. The control system 8 comprises, for example, at least one electronic card for controlling the position of the output element and one electronic card for controlling the position of the electric motor. The control system 8 is a system for monitoring the angular position of a geared motor, in particular for monitoring the angular position of the motor shaft 18 and that of the output element 35, 37.

[0041] In practice, the control system 8 comprises for example at least one printed circuit 80, 81 and a microcontroller 82 which is assembled to the printed circuit 80, 81. The microcontroller 82 can in particular integrate the control unit, the sensor 40 of angular position of the motor shaft and / or the sensor 42 of position of the movable element. In each of the embodiments shown, the sensor 42 of angular position of movable element is assembled to a first printed circuit 80 and the sensor 40 of angular position of output element is assembled to a second circuit printed 81. In each of the embodiments shown, the movable element is the output element 35, 37 of the geared motor 2.

[0042] Preferably, one of the output element angular position sensor 40 and the movable element angular position sensor 42 is an incremental encoder while the other is an absolute encoder. In the embodiments shown, the output element angular position sensor 40 is an incremental encoder and the movable element angular position sensor 42 is an absolute encoder.

[0043] The motor shaft angular position sensor 40 is configured to detect the angular position of a shaft 18 of an electric motor of a geared motor 2, from the determination of the position of the rotor 14 of the electric motor. The motor shaft angular position sensor 40 determines the position of the rotor 14 from the evaluation of counter electromotive force which is generated by currents induced in the unexcited coils 22 of the electric motor 4. The motor shaft angular position sensor 40 is a revolution counter.

[0044] The movable element angular position sensor 42 is preferably configured to detect the angular position of the output element 35, 37 of the geared motor 2. In each of the embodiments shown, the movable element angular position sensor 42 is a Hall effect sensor. The Hall effect sensor may be a one-dimensional, two-dimensional, and / or three-dimensional Hall effect sensor. The movable element angular position sensor 42 is located outside the gear shafts 30 and at a distance from the output element 35, 37. It cooperates with a detection magnet 44 which is fixed to the outside of the output element 35, 37. The magnet 44 is for example a permanent magnet which is made of iron, ferrite, cobalt, or an alloy comprising at least one of these materials such as alnico.

[0045] The control unit is for example part of the microcontroller 82. It is configured to determine the angular position of the output element 35, 37 from the detection of the angular position of the motor shaft 18 by the motor shaft angular position sensor 40. It is also configured to determine the angular position of the output element 35, 37 from the detection of the angular position of the output element 35, 37 by the output element 35, 37 angular position sensor 42. The control unit implements the angular position control method 100, 200 as described below, from the measurements of the sensors 40, 42 of the control system 8.

[0046] Figure 4 illustrates a method 100 for controlling the angular position of the output element 35, 37 according to the first embodiment of the invention. In general, the control method 100 comprises a final step 109 of controlling the angular position x(t) of the geared motor output element by the control system 8. The final step 109 of controlling the angular position x(t) comprises a determination mination 105 of angular position of geared motor according to equation 1: x(t) = Sp(tO) + K*Yr(t) from the detection of the angular position of the motor shaft 18 by the motor shaft angular position sensor 40. In addition or alternatively, the final control step 109 of the angular position x(t) comprises a determination 113 of the geared motor angular position according to equation 2: x(t) = Sp(t) from a detection of the angular position of the movable element 35, 37 by the movable element angular position sensor 42. Equations 1 and 2 will be described in more detail below.

[0047] In each of the two embodiments shown, the representative value of the current detected angular position of the motor shaft is the angular position of the output element 35, 37 which corresponds to the current detected angular position of the motor shaft 18 by the motor shaft position detection sensor 40, according to equation 1. It is also called the first detected current value. The representative value of the current detected angular position of the output element is the angular position of the output element, according to equation 2, which is detected by the output element angular position sensor 42. It is also called the second detected current value.

[0048] The representative target value of angular position of the motor shaft is the angular position of the output element which corresponds to the target value of angular position of the motor shaft. It is also called the first target value Ta. The representative target value of angular position of the output element is the target value of angular position of the output element. It is also called the second target value Ta.

[0049] The sensor 40 for detecting the position of the motor shaft is called the first sensor or tachometer. The sensor 42 for the angular position of the output element is called the second sensor or Hall effect sensor.

[0050] The control method 100 starts with an initialization 101, an example of which is described in more detail with reference to FIG. 5. The initialization 101 comprises the assignment of a first reference value to the angular position of the output element x(t) according to equation 3: x(t) = Sp(tO), where Sp(tO) is a current angular position of the output element 35, 37 resulting from detection by the sensor 42 of the angular position of the output element, and tO is the start time of the control method 100.

[0051] The control method 100 then comprises a verification 103 to establish whether the determination of the angular position of the output element x(t) from the detection of the angular position of the motor shaft 18 by the first sensor 40 is working. The verification step 103 aims to be able to determine the angular position of the output element x(t), in particular in the event of failure of the position detection angular displacement of motor shaft 18 by the first sensor 40.

[0052] In the absence of failure to determine the angular position of the output element 35, 37 by detecting the angular position of the motor shaft 18, the control method 100 continues with a determination 105 of the angular position of the geared motor from the detection of the angular position of the motor shaft 18 by the first sensor 40. The angular position of the geared motor is determined from the angular position of the motor shaft 18 and the first reference value.

[0053] The representative value of the detected current angular position of the motor shaft, called the first detected current value, is used to estimate the current angular position of the output element 35, 37 according to 1' equation 1: x(t) = Sp(tO) + K*Yr(t) in which Sp(tO) is the first reference value of the angular position of the output element which was determined during initialization, K is a multiplicative factor which is characteristic of the engine and which is preferably substantially constant, and Yr(t) is a relative position of the engine shaft given by the tachometer.

[0054] Generally in the control method 100, the first current value detected according to equation 1: x(t) = Sp(tO) + K*Yr(t) is compared to the first target value taking into account a sensor tolerance ITs, during a comparison step 107. More precisely, the first current value detected x(t) is compared to the difference between the first target value Ta and the sensor tolerance ITs. The first current value detected x(t) is compared to the sum of the first target value Ta and the sensor tolerance ITs. It is at least verified whether the condition 1 Ta - ITs <x{t) = Sp ( tû ) + K*Yr ( t ) < Ta 4- ITs est remplie. La tolérance de capteur ITs est de préférence définie comme la tolérance de capteur de position angulaire le moins précis du système de contrôle 8. En pratique, la tolérance de capteur ITs correspond à la tolérance du deuxième capteur qui est à effet Hall 42 et qui est moins précis que le premier capteur 40 qui est un compte-tour.

[0055] If condition 1 is met, i.e. the first detected current value

[0056] x(t) is greater than the difference between the first target value Ta and the tolerance of sensor ITs and the first detected current value x(t) is less than the sum between the first target value Ta and the sensor tolerance ITs, the control method 100 ends with a final step 109 of control of the angular position x(t) of the geared motor output element by the control system 8, in which the first detected current value according to equation 1: x(t) - Sp(tO) + K*Yr(t) is assigned to the current angular position value of the output element 35, 37.

[0057] When the verification 103 has resulted in a finding of failure in the determination of the angular position x(t) of the output element 35, 37 from the detection of the angular position of the motor shaft 18 by the first sensor 40, the control of the angular position x(t) of the output element is carried out by the determination 113 of the angular position of the geared motor 2 from the detection of the angular position of the movable element 35, 37. The determination of the angular position x(t) of the output element 35, 37 is established according to a backup mode 111 from the second sensor 42 which allows a reliable but imprecise measurement compared to a measurement which is carried out by the first sensor 40. The backup mode 111 is considered as a degraded mode of operation of the control system 8 compared to the determination

[0058] The control method 100 comprises the determination 113 of the angular position of the geared motor from the detection of the angular position of the motor shaft 18 by the second sensor 42.The representative value of the current detected angular position of the output element, called the second current detected value, is used to estimate the current angular position of the output element 35, 37 according to equation 2: x(t) = Sp(t) in which Sp(t) is the current detected value of the detected angular position of the output element 35, 37 by the second sensor 42. .

[0059] The second current value detected according to equation 2: x(t) = Sp(t) is compared to the second target value Ta taking into account a sensor tolerance ITs, during a comparison step 115. More precisely, the second detected current value x(t) is compared to the difference between the second target value Ta and the sensor tolerance ITs. The first detected current value x(t) is also compared to the sum of the second target value Ta and the sensor tolerance ITs. It is at least verified whether condition 3 Ta-ITs < x{t} — Sp(t) < Ta + ITs is fulfilled. The second target value is very preferably equal to the first target value of condition 1. The sensor tolerance is very preferably equal to that of condition 1.

[0060] If condition 3 is met, i.e. the second detected current value

[0061] x(t) is greater than the difference between the second target value Ta and the tolerance of sensor ITs and the second detected current value x(t) is less than the sum between the second target value Ta and the sensor tolerance ITs, the control method 100 ends with the final step 109 of control of the angular position x(t) of the geared motor output element by the control system 8, in which the second detected current value according to equation 2: x(t) = Sp(t) is assigned to the current angular position value of the output element 35, 37.

[0062] The initialization 101 of the control method 100, i.e. the assignment of a first reference value to the detected current position value x(t) of the output element is described in detail with reference to [Fig. 5]. The start 301 of the initialization is carried out each time the geared motor 2 is started, i.e. in particular after each power cut of the geared motor 2 that is long enough to cause a loss of data from the rev counter 40. The start 301 of the initialization of the reference angular position of the output element is carried out with the verification 303 of the absence of a reference angular position of the geared motor 2, in particular the absence of a reference angular position of the output element 35, 37. In the event of the absence of a reference angular position of the output element 35, 37, the angular position of the output shaft is detected, preferably several times, by the second sensor 42 according to a preliminary detection 305. A reference angular position of the output element is established in the step 307 of determining a reference value from the angular position detections of the output element, for example by averaging the measurements from the preliminary detection 305.The angular position of the output element is initialized in the final initialization step 309 with the angular position reference value.

[0063] [Fig. 6] illustrates a control method according to a second embodiment which differs from that according to the first embodiment, by the verification step 203, comparison 207, and change of position 221 of the electric motor. The other steps 101, 105, 109, 111, 113 and 115 are identical between the two embodiments and they will not be described again in detail in connection with the second embodiment.

[0064] The verification 203 aims to establish whether the determination of the angular position of the output element x(t) from the detection of the angular position of the motor shaft 18 by the first sensor 40 works. The verification 203 is implemented by counting the number of failures Cx to determine the angular position of the output element 35, 37 from the detection of the angular position of the motor shaft 18 by the first sensor 40. The verification 203 is in particular implemented by comparing the number of failures Cx to determine the angular position of the output element 35, 37 from the detection of the angular position of the motor shaft 18 with a maximum number of admissible failures LCx.If during the verification 203, it is determined that the number of failures Cx for determining the angular position of the output element 35, 37 from the detection of the angular position of the motor shaft 18 is less than the maximum number of admissible failures LCx, a determination 105 of the geared motor angular position x(t) is again attempted from the detection of the angular position of the motor shaft 18. Failing this, the control method 200 continues with the determination 113 of the angular position of the output element from the detection of the angular position of the movable element 35, 37.

[0065] During comparison 207, it is also checked whether condition 1 Ta - JT s < x ( t ) = Sp ( tO ) 4- K*Y r ( t ) < Ta + ITs is fulfilled. It is also verified if a condition 2 <Sp(t)-ITs<x(t) - Sp(tO) + K* Yr(t) <Sp(t) +ITs est remplie, contrairement à l’étape de comparaison du procédé de contrôle 100 selon le premier mode de réalisation. La condition 2 revient à vérifier si la position angulaire x(t) de l’élément de sortie qui est établie à partir du premier capteur 40 est égale à la valeur de position angulaire actuelle détectée Sp(t) de l’élément de sortie 35, 37 par le deuxième capteur 42 aux tolérances de capteur ITs près. En particulier, il est vérifié si la valeur représentative de position angulaire actuelle détectée de l’arbre de moteur x(t) = Sp(tO) + K*Yr(t) est supérieure à une différence entre la valeur représentative de position angulaire actuelle détectée de l’élément mobile Sp(t) par le deuxième capteur 42 et la tolérance de capteur ITs.It is checked whether the detected current angular position representative value of the motor shaft x(t) = Sp(tO) + K*Yr(t) is less than a sum between the detected current angular position representative value of the movable element Sp(t) by the second sensor 42 and the sensor tolerance ITs. If condition 1 and condition 2 are verified, the control method 200 continues with the final control step 109 by assigning the first detected current value according to equation 1: x(t) = Sp(tO) + K*Yr(t) to the current angular position value of the output element.

[0066] In the case where condition 1 and condition 2 are not simultaneously fulfilled during the comparison step 207, it is checked during a position change determination step 221 whether only condition 2 is satisfied. If this is the case, it is determined that the angular position of the geared motor 2 is varying during a current movement of the motor shaft 18 and the output element 35, 37. The determination 105 of the geared motor angular position according to equation 1: x(t) = Sp(tO) + K*Yr(t) is updated to take this movement into account. If during the position change determination step 221, it is determined that condition 2 is not satisfied, then it is considered that the determination of the angular position of the output element 35, 37 from the detection by the first sensor 40 is a failure and this failure is counted for the verification step 203.

[0067] Thanks to the invention as claimed, the angular position of a geared motor 2, in particular of an output element 35, 37 of the geared motor 2, can be known precisely, while having a robust measurement of the position of the geared motor 2, and while having a control system 8 which is easy to manufacture, install and use.

[0068] In particular, the manufacture of the control system 8 is facilitated by avoiding a precise and expensive Hall effect sensor 42. The moving element angular position sensor 42 then cooperates in particular with a magnet 44 for a Hall effect sensor which is free of rare earth. The magnet 44 is for example made of a material constituent which is devoid of neodymium, in particular an alloy of neodymium iron and boron.

[0069] In particular, the use of the control system 8 is facilitated by dispensing with a Hall effect sensor 42 which is difficult to assemble to the reducer 6. The Hall effect sensor 42 is for example entirely located outside the shafts 30 of the geared motor, and a magnet 44 for the Hall effect sensor is in particular fixed to an output transmission element 37. The Hall effect sensor 42 is in particular of the “Off Axis” type as opposed to a Hall effect sensor 42 of the “On Axis” type which is at least partially located inside the output element 35 of the geared motor. The centering of the geared motor shafts 30 is facilitated.

[0070] The angular position of the electric motor shaft 18 and that of the output element 35, 37 of the geared motor are determined precisely in normal operation of the control system 8 for controlling the angular position of the geared motor 2. In normal operation of the control system 8, that is to say in the absence of failure to determine the angular position of the output element 35, 37 from the detection of the position of the motor shaft 18, the position of the output element 35, 37 is known precisely from the detection of the position of the motor shaft 18 by the motor shaft angular position sensor 40. In normal operation, the angular position of the output element 35, 37 is determined from the measurement of the revolution counter 40 which is precise, unlike the measurement of the Hall effect sensor 42.

[0071] The angular position of the electric motor shaft 18 and the angular position of the output element 35, 37 of the geared motor are in particular known reliably, in particular regardless of the conditions of use of the geared motor 2. In the event of failure to determine the angular position of the geared motor 2 from the detection of the position of the motor shaft 18, in particular in the event of failure of the motor shaft position sensor 40, the angular position of the geared motor 2 is known reliably by measuring the angular position of the output element 35, 37 by the output element angular position sensor 42. In the event of failure of the tachometer 40, the Hall effect sensor 42 makes it possible to reliably know the angular position of the motor shaft 18 and that of the output element 35, 37.

[0072] Of course, various modifications can be made by those skilled in the art to the invention which has just been described without departing from the scope of the disclosure of the invention.

[0073] Alternatively, the motorized vehicle is a two-wheeled or three-wheeled or more-wheeled motorized vehicle, for example a motorcycle, a van or a truck.

[0074] Alternatively, the valve 1 is a hydraulic valve of a fluid system other than fuel, for example a hydraulic valve of a wiper fluid system. ice or a lubrication system. The fluid is, for example, oil, windshield wiper fluid or coolant.

[0075] Alternatively, the electric motor 4 is for example a brushed motor. Alternatively, the electric motor 4 is an asynchronous motor.

[0076] As a further variant, the coils 22 are on the rotor 14 and the magnets are on the stator 20.

[0077] As a variant, the movable element is another shaft 30 of the reducer than the output shaft 35. As a further variant, the movable element is another transmission element 32 of the reducer than the output transmission element 37.

[0078] Alternatively, the control system 8 comprises a microprocessor instead of the microcontroller 82, for example when the control system 8 comprises a computer or a smartphone.

[0079] Alternatively, the Hall effect sensor 42 is an “On Axis” sensor which is for example located inside the output shaft 35, which makes it possible to improve the precision of the Hall effect sensor 42 at the expense of the ease of manufacturing the reducer 6.

[0080] Additionally or alternatively, the magnet 44 cooperating with the Hall effect sensor comprises a rare earth, for example neodymium in the form of a neodymium alloy. The accuracy of the Hall effect sensor 42 is improved accordingly.

[0081] Alternatively, the motor shaft angular position sensor 40 comprises a type of sensor other than a revolution counter, for example an optical encoder and / or a potentiometer. Additionally or alternatively, the output element angular position sensor 42 comprises a type of sensor other than a Hall effect sensor, for example an optical encoder and / or a potentiometer.

[0082] Alternatively, the initialization 300 is carried out from a single measurement by the second sensor 42 during the preliminary detection 305. Alternatively, the aberrant angular position measurements are eliminated during the preliminary detection 305, or during the remainder of the control method 100, 200.

[0083] Alternatively, the duration of attempts to determine the angular position of the output element 35, 37 from detection by the first sensor 40 is counted, rather than the number of failures Cx to determine the angular position of the output element 35, 37 from detection by the first sensor 40. The duration of attempts to determine the angular position of the output element 35, 37 from detection by the first sensor 40 and the number of failures Cx to determine the angular position of the output element 35, 37 from detection by the first sensor 40 may also be counted jointly to assess the advisability of determining the angular position of the output element 35, 37 by detecting the angular position of the output element 35, 37 by the second sensor 42.

[0084] Alternatively, the representative value of the detected angular position of the motor shaft is the detected angular position of the motor shaft. The representative value of the detected angular position of the output member is the angular position of the motor shaft which corresponds to the angular position value of the output member which is detected by the output member angular position sensor. The representative target value of angular position of the motor shaft is the target value of angular position of the motor shaft. And the representative target value of angular position of the output member is the angular position value of the motor shaft which corresponds to the target value of angular position of the output member.

[0085] Alternatively, the sensor tolerance corresponds to a maximum margin of error of the motor shaft angular position sensor 40.

Claims

Claims

1. Method for controlling the angular position (100, 200) for a motorized vehicle comprising a step of controlling the angular position of a geared motor (x(t)) comprising a motor, itself comprising a rotor, a stator and an output shaft (18), and a reducer (6), by a control system (8) for controlling the angular position of a geared motor (2) for a motorized vehicle, comprising: - a sensor (40) for the angular position of the motor shaft, configured to detect the angular position of said shaft (18) from the determination of the position of the rotor (14) of the electric motor, - a sensor (42) for the angular position of a movable element, configured to detect the angular position of a movable element (35, 37) of the reducer (6), the movable element (35, 37) being a shaft (35) of the reducer or a transmission element (37) of the reducer, the step (109) of controlling the angular position of the geared motor comprising: a determination (105) of the angular position of the geared motor (x(t) = Sp(tO) + K*Yr(t)) from the detection of the angular position of the motor shaft (18) by the motor shaft angular position sensor (40), and / or a determination (113) of the angular position of the geared motor (x(t) = Sp(t)) from a detection of the angular position of the movable element (35, 37) by the movable element angular position sensor (42), this method comprising a determination (105, 109) of the angular position of the movable element (35, 37) of the geared motor from the detection of the angular position of the motor shaft (18) by the motor shaft angular position sensor (40), when a representative value of the current detected angular position of the motor shaft (x(t) = Sp(tO) + K*Yr(t)) is greater than the difference between a target value (Ta) representative of the angular position of the motor shaft and a sensor tolerance (ITs), and the representative value of the current detected angular position of the motor shaft (x(t)) is less than a sum of the target value (Ta) representative of the angular position of motor shaft and sensor tolerance (ITs),the representative value of the current detected angular position of the motor shaft (x(t)) being representative of a current angular position detected by the motor shaft angular position sensor (x(t) =, Sp(tO) + K*Yr(t)).

2. An angular position control method (100, 200) according to the preceding claim, comprising checking (207, 221) whether a detected current angular position representative value of the motor shaft (x(t) = Sp(tO) + K*Yr(t)) is greater than a difference between a detected current angular position representative value of the movable element (Sp(t)) and the sensor tolerance (ITs), and checking (207, 221) whether the detected current angular position representative value of the motor shaft (x(t) = Sp(tO) + K*Yr(t)) is less than a sum of the detected current angular position representative value of the movable element (Sp(t)) and the sensor tolerance (ITs), the detected current angular position representative value of the movable element (Sp(t)) being representative of a current angular position detected by the movable element angular position sensor (42).

3. Angular position control method (100, 200) according to the preceding claim, comprising an angular position change (221, 105) of the electric motor, when a detected current angular position representative value of the motor shaft (x(t) = Sp(tO) + K*Yr(t)) is greater than the difference between the detected current angular position representative value of the movable element (Sp(t)) and the sensor tolerance (ITs), and the detected current angular position representative value of the motor shaft (x(t) = Sp(tO) + K*Yr(t)) is less than a sum of the detected current angular position representative value of the movable element (Sp(t)) and the sensor tolerance (ITs), and the detected current angular position representative value of the motor shaft (x(t) = Sp(tO) + K*Yr(t)) is far from the target angular position representative value (Ta) of the motor shaft beyond the sensor tolerance (ITs).

4. Angular position control method (100, 200) according to any one of the preceding claims, comprising a determination (109, 113) of the angular position of the geared motor (x(t) = Sp(t)) from the detection of the angular position of the movable element (35, 37) by the movable element angular position sensor (42), in the event of failure (103, 111) to determine the angular position of the geared motor from the detection of the angular position of the shaft (18) motor by the control system (8), the control method (100, 200) identifying in particular a failure to determine the angular position of the geared motor from the detection of the angular position of the motor shaft, when a number of attempts to determine the angular position of the geared motor from the detection of the angular position of the motor shaft is greater than a threshold value of attempts (203) and / or when a duration of determination of the angular position of the geared motor from the detection of the angular position of the motor shaft is greater than a threshold duration.

5. An angular position control method (100, 200) according to the preceding claim, comprising determining (113, 109) an angular position of the geared motor (x(t) = Sp(t)) from the angular position detection of the movable element, when a detected movable element angular position (x(t)) is greater than the difference between a target value (Ta) of movable element angular position and a sensor tolerance (Ts), and the current detected movable element angular position (x(t)) is less than a sum of the target value (Ta) of movable element angular position and a sensor tolerance (Ts).

6. Angular position control method (100, 200) according to any one of the preceding claims 1 to 5, comprising an initialization step (300, 101) which comprises a calibration of the motor shaft angular position sensor (40) at each start of the electric motor (4) and / or at each cutoff of the electrical power supply to the electric motor (4), and / or in which the initialization step (300, 101) comprises at least one detection (305) of the angular position of the movable element by the movable element angular position sensor (42).

7. Control method (8) according to one of the preceding claims, in which the motor shaft angular position sensor (40) is a revolution counter, the determination of the position of the rotor (14) of the electric motor being in particular from the evaluation of a counter electromotive force which is generated by currents induced in non-excited coils (22) of the electric motor (4).

8. Control method (8) according to any one of the preceding claims, in which the movable element angular position sensor (42) is a Hall effect sensor, this sensor preferably being assembled to a printed circuit (81) of an electronic card of the control system (8), this sensor preferably being located outside the shaft of the geared motor and at a distance from the moving element (35, 37).

9. Control method (8) according to any one of the preceding claims, wherein the control system (8) comprises a control unit (82) which is configured to determine the angular position of the geared motor (2) from the detection of the angular position of the motor shaft (18) by the motor shaft angular position sensor (40) and / or from the detection of the angular position of the movable element by the movable element angular position sensor (42), the control system (8) preferably being configured to control the angular position of the movable element (35, 37), which is preferably an output transmission element (37) or an output shaft (35) of the geared motor (2).

10. Method according to any one of the preceding claims, in which the motor (4) is a permanent magnet synchronous electric motor for a fluid circulation system of a motor vehicle, and / or in which the geared motor (2) is a geared motor (2) of a fluid circulation valve (1) for a motor vehicle, the geared motor (2) being in particular a geared motor (2) of a liquid circulation valve (1) of a cooling system for a motor vehicle.

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