EP3345682A1 - Alarm system, assembly comprising a spraying device and such an alarm system and air spraying process - Google Patents

Abstract

An alarm system is provided for sending an alarm signal to a user with a spraying device when the spraying distance is less than a minimum value or greater than a maximum value. In addition, an alarm signal may also be sent when there is a defect of perpendicularity between a spraying axis of the device and a surface to be coated (S3 ') disposed facing the spraying device. The alarm system comprises at least one means (30, 32) for measuring a spraying distance (d1, d2) with a surface to be coated (S3 ') disposed facing the spraying device. The alarm system may also include means (30, 32) for detecting a perpendicularity defect between the spraying axis (X2) and the surface to be coated (S3 ').

Description

The invention relates to an alarm system for a spraying device, in particular for a gun designed to be handled by a user.

Known in the field of manual spraying devices, manual spray guns with an actuating trigger are known. When the painter actuates the trigger, an electronic system on the gun checks if the gun is at a suitable distance from the object to be coated and opens the paint valve if necessary. The problem with this type of gun is that the painter may suffer from musculoskeletal disorders (MSDs) due to repeated actuation of the trigger.

To overcome these disadvantages, some guns have no trigger. This type of gun includes a sensor for measuring the spray distance and a nozzle, the opening of which is selectively controlled by the movement of a needle. The distance sensor triggers the opening and closing of the needle automatically according to the distance between the gun and the part to be coated. To project the coating product, the user then has to point the gun towards the part to be coated. A disadvantage, however, of this 100% automatic mode is that the gun can continue to spray in an uncontrollable manner. Indeed, if the painter puts the gun on the ground, for example near a wall, then the gun can start and project the product on the wall, which is obviously not desirable. This type of gun is not suitable for beginner painters.

Furthermore, inexperienced painters often find it difficult to hold the pistol so as to maintain the perpendicularity between the projection axis of the pistol and the surface to be coated. This lack of perpendicularity leads to poor application of the product and defects in finish (oversizes, overflow, etc ...). Some guns are equipped with means for measuring the angle of the spray relative to the surface of the object to be coated and a valve that automatically adjusts the flow of the coating product according to the inclination of the gun relative to the surface to be coated. When the gun is oriented to obtain an optimum spray angle, the flow is increased. On the other hand, the flow is decreased when there is a defect of perpendicularity. Systematically, the flow is also adjusted according to several parameters, such as the surface condition, the temperature, the speed of the gun relative to the object, the geometry of the surface, etc.

Thus, it is difficult for a nonprofessional painter to determine the origin of a drop in flow and thus to correct the behavior of the gun accordingly.

In addition, certain spray guns, commonly known as AIRMIX spray guns (registered trademark), include a spray air injection system. This system comprises air ejection holes and the high pressure jets from these holes impact the jet of coating product at the nozzle outlet, so as to form a homogeneous atomized spray in the form of droplets. In this type of gun, the product injection system and the spray air injection system are sequentially opened when the user presses the trigger: the air injection system is activated first and the product injection system is activated second. So we have a double-action trigger.

The invention provides an alarm system to facilitate the use of a spray device and thus make the device usable even by novice painters.

For this purpose, the invention relates to an alarm system, designed to send an alarm signal to a user equipped with a spraying device when the spraying distance is less than a minimum value or greater than a maximum value and / or when there is a defect of perpendicularity between a spraying axis of the device and a surface to be coated arranged facing the spraying device, the alarm system comprising at least one means for measuring a spraying distance with a surface to be sprayed. coating disposed facing the spray device and / or means for detecting a defect of perpendicularity between the spray axis and the surface to be coated.

Thanks to the invention, the user of the device can be alerted when it is too close or too far from the object. Thus, he does not have to gauge the distance he is from the object to be coated and evaluate whether this distance is consistent or not with the recommendations of the manufacturer. The user can also be alerted when he does not correctly hold the device, that is to say when there is a significant perpendicularity defect between the gun spray axis and the surface to be coated. With this system, even amateur or novice painters, who generally have trouble estimating the spray distance and properly holding the spray device, can use the spray device.

• Le système d'alarme comporte un élément visuel, comportant par exemple au moins une LED, et/ou un élément sonore et/ou un vibreur.
• Le système d'alarme est déporté par rapport au dispositif de pulvérisation.
• Les moyens de mesure comprennent au moins un capteur à ultrasons ou un capteur de déplacement, tel qu'un accéléromètre.
• Les moyens de détection comprenant l'un quelconque des éléments suivants :
  • un gyroscope tridimensionnel, ou un gyroscope bidimensionnel, ou trois capteurs à ultrasons, ou au moins deux inclinomètres, ou un gyroscope unidimensionnel et un inclinomètre, ou un gyroscope unidimensionnel et deux capteurs à ultrasons.
• Le système d'alarme comprend un calculateur, qui est capable de recevoir des informations provenant du moyen de mesure et/ou des moyens de détection et qui est capable de déclencher l'émission du signal d'alarme.

According to advantageous, but not compulsory, aspects of the invention, such an alarm system may include one or more of the following features, taken in any technically permissible combination:

• The alarm system comprises a visual element, comprising for example at least one LED, and / or a sound element and / or a vibrator.
• The alarm system is remote from the spraying device.
• The measuring means comprise at least one ultrasonic sensor or a displacement sensor, such as an accelerometer.
• The detection means comprising any one of the following:
  • a three-dimensional gyroscope, or a two-dimensional gyroscope, or three ultrasonic sensors, or at least two inclinometers, or a one-dimensional gyroscope and an inclinometer, or a one-dimensional gyroscope and two ultrasonic sensors.
• The alarm system comprises a computer, which is capable of receiving information from the measuring means and / or detection means and which is capable of triggering the transmission of the alarm signal.

The invention also relates to an assembly comprising an alarm system as described above and a spraying device, such as a manual gun for example.

• Le système d'alarme est embarqué sur le dispositif de pulvérisation.
• Le dispositif de pulvérisation comprend un capteur de vitesse, tel qu'un accéléromètre, pour estimer la vitesse avec laquelle le dispositif est déplacé par rapport à un référentiel inertiel.
• L'ensemble comprend un autre système d'alarme, configuré pour alerter un utilisateur lorsqu'il déplace le dispositif de pulvérisation trop rapidement par rapport à une valeur de consigne.
• Le dispositif de pulvérisation comprend un système homme-mort, configuré pour interrompre la pulvérisation lorsque l'utilisateur est inactif ou lorsque l'utilisateur relâche le dispositif de pulvérisation, le système homme-mort comprenant de préférence un bouton poussoir, la pulvérisation étant interrompue lorsque le bouton poussoir est relâché. Autrement dit, le dispositif de pulvérisation est configuré pour pulvériser uniquement lorsque l'utilisateur exerce une action particulière sur le dispositif, qui est différente de celle consistant à presser une gâchette. Par exemple, cette action particulière peut consister à appuyer sur un bouton et/ou à prendre le dispositif en main.
• Le système homme-mort comprend un capteur de préhension capable de détecter lorsque le dispositif de pulvérisation est pris en main par un utilisateur, ce capteur de préhension étant par exemple formé par un capteur capacitif, optique ou encore thermique.
• Le système homme-mort comprend un capteur de force capable de détecter lorsque le bouton est enfoncé.
• Le capteur de préhension est intégré à une crosse de préhension du pistolet.
• Le système homme-mort est capable de transmettre un signal à une unité électronique de commande du système de fermeture d'une buse du dispositif. Ce signal est de préférence du type binaire et comprend alors deux états : « 0 » lorsque le dispositif n'est pas pris en main et/ou lorsque le bouton n'est pas enfoncé et « 1 » lorsque le capteur de préhension détecte une prise en main du dispositif et/ou lorsque le bouton est enfoncé. Aussi, le dispositif de pulvérisation est configuré pour pulvériser uniquement lorsque le signal est à l'état « 1 ».
• Le dispositif de pulvérisation est configuré pour pulvériser uniquement lorsque la distance de pulvérisation est comprise entre une valeur minimale et une valeur maximale et/ou uniquement lorsque l'angle entre l'axe de pulvérisation du dispositif et la surface à revêtir disposée face au dispositif de pulvérisation est compris entre une valeur minimale et une valeur maximale.
• L'ensemble comprend également un système indicateur de la distance de pulvérisation et/ou un système indicateur de l'orientation du dispositif par rapport à un référentiel inertiel, pour permettre à un utilisateur d'estimer la distance de pulvérisation par rapport à la valeur minimale et par rapport à la valeur maximale et/ou d'estimer l'orientation du dispositif par rapport à un degré d'orientation minimal et un degré d'orientation maximal.
• Le système indicateur est embarqué sur le dispositif de pulvérisation ou déporté par rapport au dispositif de pulvérisation, le système indicateur comprenant par exemple un écran, configuré pour être installé contre une paroi d'une cabine de pulvérisation.
• Le dispositif de pulvérisation est un dispositif sans gâchette d'actionnement.
• Le dispositif de pulvérisation comprend un moyen de communication avec un système informatique, capable de transmettre audit système informatique, en instantané ou en différé, des informations relatives à la pulvérisation, comme les temps de pulvérisation.

According to advantageous but non-mandatory aspects of the invention, such sets may incorporate one or more of the following features, taken in any technically permissible combination:

• The alarm system is embedded on the spraying device.
• The sputtering device includes a speed sensor, such as an accelerometer, for estimating the speed with which the device is moved relative to an inertial frame of reference.
• The set includes another alarm system, configured to alert a user when he moves the spraying device too quickly relative to a set value.
• The spraying device comprises a dead-man system, configured to interrupt spraying when the user is idle or when the user releases the spraying device, the man-dead system preferably comprising a push button, the spraying being interrupted when the push button is released. In other words, the spraying device is configured to spray only when the user exerts a particular action on the device, which is different from that of squeezing a trigger. For example, this particular action may consist of pressing a button and / or taking the device in hand.
• The dead-man system comprises a gripping sensor capable of detecting when the spray device is taken over by a user, this gripping sensor being for example formed by a capacitive sensor, optical or thermal.
• The dead-man system includes a force sensor capable of detecting when the button is depressed.
• The gripper sensor is integrated with a grip grip of the gun.
• The dead-man system is capable of transmitting a signal to an electronic control unit of the closure system of a nozzle of the device. This signal is preferably of the binary type and then comprises two states: "0" when the device is not taken in hand and / or when the button is not pressed and "1" when the gripping sensor detects a catch in hand of the device and / or when the button is pressed. Also, the spraying device is configured to spray only when the signal is in state "1".
• The spraying device is configured for spraying only when the spraying distance is between a minimum value and a maximum value and / or only when the angle between the spraying axis of the device and the surface to be coated arranged facing the spraying device. spraying is between a minimum value and a maximum value.
• The assembly also includes a spray distance indicator system and / or a device orientation indicator system with respect to an inertial frame of reference, to enable a user to estimate the spray distance from the minimum value. and with respect to the maximum value and / or to estimate the orientation of the device with respect to a minimum degree of orientation and a maximum degree of orientation.
• The indicator system is embarked on the spraying device or offset from the spraying device, the indicator system comprising for example a screen, configured to be installed against a wall of a spray booth.
• The spraying device is a device without actuating trigger.
• The spraying device comprises means of communication with a computer system capable of transmitting to said computer system, instantaneously or offline, information relating to the spraying, such as spraying times.

1. a) le système d'injection d'air s'ouvre lorsqu'un objet pénètre dans le champ de détection du capteur,
2. b) le système d'injection de produit s'ouvre de manière temporisée par rapport au système d'injection d'air,
3. c) le système d'injection de produit se ferme lorsque l'objet quitte le champ de détection du capteur,
4. d) le système d'injection d'air se ferme de manière temporisée par rapport au système d'injection de produit.

The invention also relates to a pneumatic spraying method, implemented by means of a spraying device comprising a proximity sensor, capable of detecting the presence of an object in a detection field, a coating product injection system and a spray air injection system. According to the invention, the method comprises the following automated steps, during which:

1. a) the air injection system opens when an object enters the detection field of the sensor,
2. b) the product injection system opens timedly with respect to the air injection system,
3. c) the product injection system closes when the object leaves the detection field of the sensor,
4. d) the air injection system closes timedly with respect to the product injection system.

1. a) le système d'injection d'air s'ouvre lorsqu'un objet pénètre dans le champ de détection de l'un quelconque des deux capteurs,
2. b) le système d'injection de produit s'ouvre lorsque l'objet pénètre dans le champ de détection de l'autre capteur,
3. c) le système d'injection de produit se ferme lorsque l'objet quitte le champ de détection de l'un quelconque des deux capteurs,
4. d) le système d'injection d'air se ferme lorsque l'objet quitte le champ de détection de l'autre capteur.

Finally, the invention relates to a pneumatic spraying method, implemented by means of a spraying device comprising two proximity sensors, arranged in such a way that the detection field of one is at least partly contained in the field. detecting the other, a coating product injection system and a spray air injection system. According to the invention, the method comprises the following automated steps, during which:

1. a) the air injection system opens when an object enters the detection field of any one of the two sensors,
2. b) the product injection system opens when the object enters the detection field of the other sensor,
3. c) the product injection system closes when the object leaves the detection field of any one of the two sensors,
4. d) the air injection system closes when the object leaves the detection field of the other sensor.

With this method, the air injection system is always open before the product injection system, which avoids the transient phase during which the spray is not quite stabilized.

Advantageously, the spraying device comprises means for electrostatically charging the coating product, which is activated before or during step a) and which is deactivated during or after step d).

Preferably, the means for electrostatically charging the coating product is activated manually, for example when operating a control member of the spray device.

• la figure 1 est une vue schématique représentant un utilisateur en train de peindre une portière au moyen d'un dispositif de pulvérisation appartenant à un ensemble conforme à l'invention,
• la figure 2 est une vue en perspective et à plus grande échelle du dispositif de pulvérisation de la figure 1,
• la figure 3 est une vue selon la flèche III à la figure 2, et
• la figure 4 est une vue partielle et en élévation du dispositif de pulvérisation, représenté face à une surface à revêtir gauche.

The invention and other advantages thereof will appear more clearly in the light of the following description, given by way of example only and with reference to the drawings in which:

• the figure 1 is a schematic view of a user painting a door by means of a spraying device belonging to an assembly according to the invention,
• the figure 2 is a perspective view and on a larger scale of the spraying device of the figure 1 ,
• the figure 3 is a view according to arrow III at figure 2 , and
• the figure 4 is a partial view in elevation of the spray device, shown facing a surface to be coated left.

On the figure 1 is shown an operator 1 spraying a coating product on a part 3 moved by a conveyor 5. The operator 1 uses for this purpose a spraying device 2. The coating product may comprise one or more compounds. It can be in fluid or powder form. This is for example a paint, a varnish, a primer, a lubricant, a solvent, etc ...

The spraying device 2 is supplied with coating material via a conduit 20 and compressed air through two conduits 22, only one of which is shown in the figures. The ducts 20 and 22 are in the example connected to a fixed power supply unit 7. In a variant, the power supply unit 7 can be a mobile device, such as a trolley or a device embedded by the user.

As visible at figure 2 the spray device 2 comprises a pistol 21. The pistol 21 comprises a grasping grip 24 to grip with the hand and a pistol body 25 secured to the upper part of the grip 24. Advantageously, the body 25 of the pistol comprises two connectors elbows 28 for the supply of compressed air and a connector 26 for the supply of coating material. A spraying nozzle 34 is fixed on the body 25. This nozzle 34 defines a spraying axis X2 according to which the jet of product is pulverized in operating condition.

Preferably, the spraying device 2 comprises at least one means for measuring the spraying distance, preferably means for measuring the spraying distance. The spray distance is the distance between the device 1 and the object to be coated 3, which is positioned facing the device 1, that is to say in the spray field of the device 1. The spray distance is measured in parallel to the X2 spray axis.

In the example, the measuring means comprise an ultrasonic sensor 30, preferably two ultrasonic sensors 30 and 32. Each of the ultrasonic sensors 30 and 32 is mounted on the body 25 of the gun 21 and is configured to emit waves. sound in a direction parallel to the X2 sputtering axis. The time with which the sound wave is reflected on the part is representative of the distance that separates the device from the part, that is to say the distance of spray.

The measuring means are connected to a computer (not shown) programmed to compare the distance values measured by the sensors 30 and 32 with a minimum value and a maximum value. The minimum value and the maximum value define a good distance range, in which the operator must be when using the device 2. The minimum and maximum values are prerecorded in a memory. They can be programmed by the user. Typically, the minimum value is greater than or equal to 10 cm, in particular equal to 15 cm, and the maximum value is less than or equal to 60 cm, in particular equal to 40 cm.

Advantageously, the spraying device 2 comprises an alarm system, designed to alert the operator 1 when the spraying distance is less than a minimum value or greater than a maximum value. The alarm system is triggered by the computer, depending on the result of the comparison of the spray distance with the minimum value and the maximum value. In the embodiment of the figures, where two ultrasonic sensors are used for calculating the distance, the distance with which the minimum value and the maximum value are compared is for example the average of the two distances, respectively d1 and d2, measured. by the sensors 30 and 32. It may also be, alternatively, the minimum distance or the maximum distance among the distances d1 and d2.

In the example, the alarm system is embedded on the spraying device 2, that is to say integrated into the device. Preferably, the alarm system comprises a vibrator 36 (shown schematically) integrated with the stick 24. This vibrator 36 vibrates when the spraying distance is less than the minimum value and when the spraying distance is greater than the maximum value, that is, when the operator is not in the right range of distance.

Advantageously, the vibrator 36 can be configured to vibrate more than the device 1 moves away from the correct range of distance.

As visible at figure 3 , the spraying device 2 advantageously comprises a dead-man system, configured to interrupt the spraying when the user is inactive.

In the example, the dead-man system comprises a control element 50 which is a push button, ergonomically arranged in the upper part of the stick 24, close to the index of the operator 1 when it grips lacrosse 24. By definition, a dead man system, also known as "automatic standby", is a system allowing the automatic triggering of an action in case of absence of movements or in the event of release from the operator . In the example, if the operator 1 is spraying a coating product and releasing the button 50, then spraying is interrupted. On the other hand, if the operator presses the button 50, then the product is sprayed.

Typically, the spraying device 1 comprises a movable needle (not shown) for closing the nozzle 34 and a closure system, configured to cause the needle to move between an open position and a closed position, and vice versa. The closure system may comprise an electromagnetic suction pad, a solenoid solenoid or a pneumatic solenoid valve which controls the arrival of the compressed air used to actuate the displacement of the needle. A return spring can be provided to ensure the closure of the needle in case of power failure.

Advantageously, the spraying device 1 integrates an electronic unit (not shown) for controlling the closure system. The electronic control unit is programmed to control the movement of the needle in the closed position when the control element 50 is not actuated. The embodiment shown in the figures thus corresponds to a 100% manual mode: the opening of the nozzle is controlled directly by the control element 50.

Preferably, the computer and the electronic control unit are a single processor.

In the embodiment considered, the electronic control unit is connected to a sensor (not shown) associated with the button 50. This sensor is intended to detect the actuation and release of the button 50 and to transmit the information to the sensor. electronic unit. For example, the sensor may generate a binary type signal, which takes the value "1" when the button 50 is depressed and the value "0" when the button 50 is released.

Advantageously, the spraying device 2 is a device without a trigger. In the field of coating product sprayers, an actuating trigger is an articulated part which is generally manipulated with the last four fingers of the hand to mechanically control the opening of the needle. In furthermore, a trigger makes it possible to adjust the flow rate of the sprayed product proportionally to the degree of actuation. The needle and the trigger are mechanically linked to each other. Conversely, in the invention, the button 50 is not mechanically linked to the needle because the displacement of the needle is electronically controlled. In addition, the button 50 does not allow the user to adjust the spraying rate. In other words, it is not a proportional button, but an ON / OFF button. With the element 50, the physical effort that the operator must provide to open the needle is much less than that which he must provide with a trigger, so that the risk of occurrence of musculoskeletal disorders (MSD) after repeated use is limited.

According to another embodiment (not shown), the spraying device 2 is voice-activated. In this case, the spray device does not include a push button or other manual control element for activating the spray. The activation and the stop of the spraying are controlled by voice instructions to be formulated orally. Thus, the spraying device 2 preferably comprises a microphone, to pick up any voice command instructions. Typically, standard instructions may be stored in memory, either in an internal memory of the device 2, or on a networked hard disk with which the device can communicate. When the user pronounces instructions corresponding to those stored in memory, then the device responds by activating or deactivating the spraying. For example, voice-activated instructions can be: "enable spraying" and "stop spraying". One could also imagine voice instructions to increase the flow of coating product and / or the level of high voltage.

In theory, the operator 1 should hold the device 2 so as to maintain the spray axis substantially perpendicular to the surface to be coated. However, this can be complicated when the surface to be painted is left, such as the surface S3 'of the object 3' shown in FIG. figure 4 . However, an inexperienced user may tend to lean the spraying device 2 down, up, to the right or to the left. In this case, the X2 spraying axis is no longer perpendicular to the surface to be coated and the quality of finish may be poor. Thus, the spraying device 2 advantageously comprises means for detecting a perpendicularity defect between the spraying axis X 2 and the surface to be coated.

In the example, the detection means comprise a device for measuring the orientation of the device 2 according to one, two or three axes, in particular a gyroscope 38 (shown schematically in figure 2 ). Advantageously, the detection means also comprise the two ultrasonic sensors 30 and 32.

The gyro 38 is a unidirectional type gyroscope, configured to measure the inclination of the device about an axis, in particular around a horizontal axis Y 0, which is perpendicular to the spraying axis X 2 when the device 2 is held straight. , that is, in the configuration of the figure 1 for example. The gyro 38 thus makes it possible to evaluate the inclination of the spraying axis X 2 of the device 2 relative to the horizontal. The two ultrasonic sensors 30 and 32 make it possible for them to detect a possible defect in the orientation of the spraying device 2 around a vertical axis Z0, and therefore a defect of perpendicularity between the spraying axis X2 and the surface to be sprayed. coat S3 '. For this, a computer (not shown) compares the distance values d1 and d2 measured by the sensors 30 and 32 (see FIG. figure 4 ). The difference between the two values is representative of a defect of perpendicularity.

It is important to alert user 1 when the user is painting crookedly. Cleverly, the spraying device 2 therefore comprises an alarm system, designed to alert the user 1 when there is a defect of perpendicularity between the spraying axis X2 and the surface to be coated S3 '. Advantageously, the alarm system can be triggered when the inclination of the device 2 around the axis Y0 of the inertial reference system exceeds a threshold value chosen for example equal to 5 ° and when the difference between the distances d1 and d2 exceeds a predefined percentage, for example equal to 10%.

The alarm system is preferably the same as that used to signal a wrong spray distance. It is therefore also vibrator 36. The triggering of the alarm system is controlled by a computer, including the same computer that used to control the alarm system that is triggered to signal a wrong spray distance.

In a variant that is not shown, the means for measuring the spraying distance comprise, in place of the ultrasonic sensor or sensors, a distance sensor, such as an accelerometer coupled to a gyroscope, also called an accelerometer gyroscope. The accelerometer gyroscope is integrated in the device 1 and makes it possible to measure the acceleration of the device 1 in at least one direction, for example in the direction parallel to the spraying axis X2. Advantageously, the accelerometer is a triaxial accelerometer. A calculator integrated in the device 1 is associated with the accelerometer to calculate the displacement of the device 1, from a starting point, along 1, 2 or 3 axes by double integration in time. The starting point is a point arbitrarily chosen on the surface to be coated, such as the point P0 represented at figure 1 . In alternatively, the starting point may be a point arbitrarily chosen on a reference external to the part to be coated. In both cases, the operator performs a calibration step prior to spraying. This step is to calibrate the accelerometer by positioning the device 1 as close to the surface to be coated to set the starting point, and thus set the spray distance to zero. For example, the device may include a button (not shown) allowing the user to calibrate the accelerometer. When the operator moves back with respect to the object to be coated, the processor calculates the displacement of the device in a direction X0 substantially perpendicular to the surface to be painted, which makes it possible to obtain, at each instant, the position of the device 1 by relative to the object, and therefore a good approximation of the spray distance. Advantageously, the accelerometer can be integrated in the gyro 38.

• un gyroscope tridimensionnel, ou
• un gyroscope bidimensionnel, ou
• trois capteurs à ultrasons, ou
• au moins deux inclinomètres, ou encore
• un gyroscope unidimensionnel et un inclinomètre.

In a particular example, the button allowing the user to calibrate the distance via the accelerometer gyroscope is the control element 50. According to another variant not shown, the device comprises other means for the detection of a defect of perpendicularity. For example, the detection means may comprise any of the following:

• a three-dimensional gyroscope, or
• a two-dimensional gyroscope, or
• three ultrasonic sensors, or
• at least two inclinometers, or
• a one-dimensional gyroscope and an inclinometer.

In each case, the means used make it possible to evaluate a potential orientation fault of the device 2 around at least two axes of an inertial reference point. The third axis concerning the rotation of the device around the spraying axis X2, a measurement of the inclination of the device around this axis is not really necessary.

A three-dimensional gyroscope measures the orientation of the sputtering device 2 around three axes X0, Y0 and Z0 of a Cartesian inertial reference frame. For this, the gyroscope comprises its own reference system, defined by the axes X1, Y1 and Z1 perpendicular two by two (Cartesian mobile reference) and gives the angular position of its reference relative to the inertial reference system.

According to another variant not shown, the spraying device 2 comprises a system indicating the orientation of the device relative to an inertial reference system. The indicator system can be provided in the form of a display screen, displaying in real time tilt values of the device in one, two or three axes. The user can then correct a possible orientation fault by consulting the display screen.

According to another mode of construction, the indicator system is formed by several LEDs arranged perpendicular to the spraying axis, in particular aligned in a direction parallel to the axis Z1, so as to indicate the orientation of the device 2 around the Y1 axis with respect to the surface to be coated. Only one of these LEDs is then lit, depending on the orientation of the gun around the axis Y1 relative to the surface to be coated. When it is the middle LED of the row that is lit, this means that the spraying axis X2 is generally perpendicular to the surface to be coated. On the other hand, the other LEDs are lit when the user aims too high, or too low, with respect to the shape of the surface to be coated. Similarly, a row of LEDs can also be provided in the direction parallel to the axis Y1, as a system indicating the orientation of the device 2 around the axis Z1. The LEDs can also be arranged in an arc.

The indicator system is therefore configured to allow a user to estimate the orientation of the device 2, in one, two or three axes, with respect to a minimum degree of orientation and a maximum degree of orientation. The degree of minimum orientation and the degree of maximum orientation are angles measured relative to the normal of the surface to be coated. With this system, the user can identify with respect to the orientation values not to exceed and thus orient the device 2 optimally, trying to orient the device in the middle of the race between the degree of orientation minimum and the maximum degree of orientation. When the device 2 is oriented optimally, that is to say when the degree of orientation is 0 °, the spray axis is perpendicular to the surface to be coated.

According to another variant not shown, the electronic control unit of the closure system of the nozzle 34 is programmed to automatically move the needle in the closed position when the spray distance is less than a threshold terminal less than or equal to the minimum value 10 cm and / or when the spraying distance is greater than a threshold limit greater than or equal to the maximum value of 60 cm. This is called a safety zone between 0 and 10 cm, which cuts the spray device 2 when there is something in the field. This advantageously protects the user, by interrupting the spray, when it places his hand in front of the nozzle for example.

Thus, it can be envisaged to first warn the user that the spraying distance is not correct and to then automatically interrupt the spraying if the spray distance becomes really critical (too close or too far away). In this variant, the means for measuring the spraying distance are connected to the electronic control unit so as to be able to transmit measurement information, in particular the value of the spraying distance.

According to another variant not shown, the electronic control unit of the closure system of the nozzle 34 is programmed to automatically move the needle in the closed position when the inclination angle of the device 2 around the axis Y0 is greater at a predetermined value, greater than or equal to the threshold value (of 5 ° in the example) and when the difference between the values d1 and d2 exceeds a certain percentage, greater than or equal to 10% for example Thus, it can be envisaged first to prevent the user that the device 2 is misdirected and then automatically interrupt the spray if the orientation of the device 2 becomes really critical. In this variant, the means for detecting a perpendicularity defect are connected to the electronic control unit so as to be able to transmit measurement information, in particular the inclination values.

According to another variant not shown, the spraying device 2 is a device of the semi-automatic type. The device 2 then simply comprises a security element, designed to oppose the spraying of the coating product as the device is not held in hand by a user. For example, this security element may be a detent or a button, operable between a locked position, in which it opposes the spraying of the coating material and an unlocked position, wherein the coating product can be sprayed automatically when an object is detected in front of the device, that is to say in the spray field of the device.

According to another variant not shown, the "dead man" system is formed by a gripping sensor, capable of detecting when the spraying device 2 is taken in hand by a user. This gripping sensor can be a capacitive sensor, an optical sensor or a thermal sensor. In the latter case, the thermal sensor is integrated with the gripping stick 24 and detects the human heat applied to the butt 24 when the user takes control of the device 2. The gripping sensor is capable of transmitting a signal to the user. electronic control unit of the closing system of the nozzle 34 of the device 2. This signal is preferably of the binary type and then comprises two states: "0" when the device 2 is not taken in hand and "1" when the gripper sensor detects a grip of the device 2. Thus, the "dead-man" control element is configured to stop the spraying when the user releases the device 2, that is to say, releases the butt 24.

According to another variant not shown, the spraying device 2 comprises an indicator system, to inform the user of the spray distance. This indicator system may be a display system, such as a screen, for displaying in real time the spray distance. This screen can also display the minimum and maximum distance values to be respected when coating a room. The user then has all indications within sight to spray the product at a good distance.

In a variant, the indicator system comprises several LEDs, for example 5 LEDs, aligned in the direction of the spraying axis. An LED is then lit depending on the spray distance. For example, the third LED (middle LED) may be lit when the user is approximately in the middle of the recommended range.

The indicator system is therefore configured to allow a user to estimate the spray distance with respect to the minimum value and the maximum value recommended.

In all the embodiments concerned, the indicator system can be offset with respect to the spraying device 2. For example, when the indicator system is a display screen, it can be installed against a wall of a booth. spraying (not shown).

According to another variant not shown, the alarm system comprises, in place of the vibrator 36 or in addition, a visual indicator, comprising at least one LED and / or a sound indicator, of the "beep" or "buzzer" type. The LED can be provided to flash with a frequency that is higher as the operator moves away and / or approaches the correct distance range or the angle of inclination of the device relative to the one axes of the inertial reference frame increases. Likewise, the intensity and / or the frequency of the "beep" may be provided to increase as the operator moves away from the correct distance range or the perpendicularity defect is important. Also, the visual indicator may comprise several LEDs, for example three LEDs of different colors (1 green LED, 1 orange LED and 1 red LED), or a variable color LED. Advantageously, the green color can be used to indicate that the perpendicularity is correct or that the user is in the right range of distance, the orange color can be used to signal a slight defect of perpendicularity or that the user has reached the terminals (lower and upper) of the recommended distance range and the Red color can be used to signal a severe perpendicularity defect or the spray distance is outside the recommended range.

In all the embodiments concerned, the rows of LEDs may be formed by RGB lighting, comprising an LED strip, an RGB controller and a specific light source.

According to another variant not shown, the spraying device 2 comprises a speed sensor, such as an accelerometer, for estimating the speed with which the device is moved relative to a fixed reference. Indeed, the manufacturers of manual spraying devices recommend scanning speeds for moving the device relative to a surface to be coated. The accelerometer is designed to measure, by integration with respect to time, the speed of the device in a direction perpendicular to the spray axis (one-dimensional accelerometer), preferably in two or three perpendicular directions two by two (two-dimensional accelerometer or three-dimensional ). Advantageously, an alarm system as described above (visual, sound and / or vibratory) is triggered when the operator moves the device 2 too quickly, that is to say at a speed greater than the speed recommended by the manufacturer. Product spraying can also be interrupted. For this, the electronic control unit of the closure system of the nozzle is connected to the speed sensor, to compare the speed value or values measured by the sensor with a prerecorded value in memory, in accordance with the recommendations of the manufacturers. Of course, this value is configurable.

According to another variant not shown, the device 2 comprises a counting system of the number of opening and closing sequences of the nozzle 34, that is to say the number of times the operator has pressed the button. 50 for a 100% manual sprayer. Advantageously, the device 2 may also comprise a means of communication with a computer system, for example with a computer. This means of communication may be a radio antenna, an RFID transmitter / receiver also called "RFID transceiver" in English, an NFC chip, a Wi-Fi antenna, etc ... Information relating to the number of opening sequences and closure of the nozzle 34 can then be transmitted to the computer system, which can in particular to estimate the wear of the seals of the device 2 and to program a preventive maintenance operation. This information can also be communicated to the user through a display system, such as a screen, if the device is equipped. Also, the device 2 can transmit to the system computer, instantaneous or delayed, information relating to the spraying times. Based on this information and the coating product flow rate of the device 2, the system can then calculate the amount of spray coating product and the amount of coating material remaining in the supply box 7.

According to another variant not shown, the alarm system is distinct from the spraying device 2 and is offset relative thereto. It may for example be formed by a "buzzer" or a light beacon arranged inside the spray booth. In this case, the on-board computer on the spraying device 2 communicates with the alarm system via a wireless transmission system (radio, Wi-Fi, etc.).

In addition, in the example of the figures, the means for measuring the spraying distance and the means for detecting a perpendicularity defect are incorporated into the gun during manufacture. In variant not shown, these means could be integrated into the alarm system, which would be removable relative to the gun. The alarm system would then take the form of an accessory that would selectively connect to a port of the gun.

The characteristics of the embodiment described above and the different variants not shown can be combined with one another to generate new embodiments of the alarm system and consequently of the whole.

The spraying device 2 makes it possible to implement a pneumatic spraying method according to the invention.

The ultrasonic sensors 30 and 32 are proximity sensors, each of which has a detection cone, respectively C1 and C2. The sensors 30 and 32 are arranged in such a way that the detection field of one is partly contained in the detection field of the other. This means that there is an area of overlap, ie an area covered by both sensors at once. In the example, the sensors 30 and 32 are ultrasonic sensors, so that their detection field is formed by a cone, which is why it is referred to as a detection cone.

The spraying device 2 comprises a coating product injection system and a spray air injection system, comprising in particular the air inlets 22 and the closing valves of the ducts 22 (not shown). The product injection system advantageously comprises the nozzle 34 and a closing needle of the nozzle (not shown).

The spray air makes it possible to spray the product in the form of a spray, that is to say in fine droplets. This is the principle of pneumatic spraying.

When the user moves the device 2 horizontally from left to right, the sensor 32 begins to detect the presence of an object 3 'in its detection field. This presence detection causes the opening of the injection air injection system: the system valves open and the device 2 blows air. The object 3 'is then detected by the sensor 30, which causes the opening of the product injection system. There is therefore a delay between the opening of the air injection system and the opening of the product injection system. This delay makes it possible to avoid the transient period during which the jet of product is not stabilized.

When the user reaches the end of the object 3 ', the latter leaves the detection field of the sensor 32, but nevertheless remains in the detection field of the sensor 30. This causes the closure of the injection system. product. The device 2, however, continues to blow air. The object 3 'then leaves the detection field of the sensor 30, which causes the closure of the air injection system. There is therefore a time delay between the closure of the product injection system and the closure of the air injection system. This delay saves the amount of coating material used when spraying the product chain on parts conveyed along a production line and also when going back and forth on the same piece or when the coating is applied to a part with openings.

In practice, the sensors 30 and 32 send signals to an electronic control unit, able to control the opening and closing of the product injection system and the air injection system. These signals are advantageously of the analog and / or digital type.

In the example of the figures, the device 2 comprises two proximity sensors offset relative to each other in a horizontal plane and along an axis perpendicular to the spray axis when the device 2 is taken in hand. However, in a variant not shown, the two sensors could be offset perpendicularly, that is to say along a vertical axis when the device 2 is taken in hand.

Also, the two sensors 30 and 32 could be integrated with each other. A first of the two sensors comprises a wider detection field than the second sensor. For example, the detection cone of the first sensor may have a half-angle of 30 ° while the detection cone of the second sensor may have a half-angle of 20 °. In this configuration, the detection field of the second sensor is entirely contained in the detection field of the first sensor.

In this embodiment, the air injection system opens when an object enters the detection field of the first sensor, i.e. the sensor with the widest detection field. The product injection system opens thereafter when the object enters the detection field of the second sensor. The product injection system closes when the object leaves the detection field of the second sensor and the air injection system closes when the object leaves the detection field of the other sensor.

According to another variant not shown, the spraying device 2 comprises a single proximity sensor, for example any of the sensors 30 and 32. In this embodiment, the air injection system opens when an object enters the detection field of the sensor and the product injection system opens timedly with respect to the air injection system. In the same way, the product injection system closes when the object leaves the sensing field of the sensor and the air injection system closes timedly with respect to the product injection system.

According to another variant not shown, the spraying device 2 comprises means for electrostatically charging the coating product, which is activated before or during the opening of the air injection system and which is deactivated during or after the closure of the device. air injection system. Preferably, the means for electrostatically charging the coating product is activated manually, for example during the operation of the control element 50 of the spraying device 2.

The features of the embodiment described above and the different variants not shown can be combined with each other to generate new embodiments of the method.

Claims (15)

Alarm system, designed to send an alarm signal to a user equipped with a spraying device (2) when the spraying distance (d1, d2) is less than a minimum value or greater than a maximum value and / or when there is a defect of perpendicularity between a spraying axis (X2) of the device and a surface to be coated (S3 ') disposed opposite the spraying device, the alarm system comprising at least one means (30, 32) measuring a spray distance (d1, d2) with a surface to be coated (S3 ') disposed opposite the spray device and / or means (30, 32, 38) for detecting a perpendicularity defect between spraying axis (X2) and the surface to be coated (S3 '). Alarm system according to claim 1, comprising a visual element, comprising for example at least one LED, and / or a sound element and / or a vibrator (36). Alarm system according to claim 1 or 2, wherein the alarm system is offset from the spraying device. Alarm system according to one of the preceding claims, wherein the measuring means comprise at least one ultrasonic sensor (30, 32) or a displacement sensor, such as an accelerometer. Alarm system according to one of the preceding claims, wherein the detection means comprise any one of the following: a three-dimensional gyroscope, or a two-dimensional gyroscope, or - three ultrasonic sensors, or - at least two inclinometers, or a one-dimensional gyroscope and an inclinometer, or a one-dimensional gyro (38) and two ultrasonic sensors (30, 32). Assembly comprising an alarm system (36) according to one of the preceding claims and a spraying device (2), such as a manual gun for example. An assembly according to claim 6, characterized in that the alarm system is embarked on the spraying device (2). Assembly according to one of claims 6 and 7, characterized in that the spray device (2) is configured to spray only when the user exerts a particular action on the device, which is different from that of pressing a trigger, this particular action of, for example, pressing a button (50) and / or taking the device in hand. Assembly according to one of claims 6 to 8, characterized in that the spray device is configured to spray only when the spray distance (d1, d2) is between a minimum value and a maximum value and / or only when the The angle between the spray axis (X2) of the device and the surface to be coated (S3 ') disposed opposite the spray device is between a minimum value and a maximum value. Assembly according to one of Claims 6 to 9, characterized in that the assembly also comprises a system for indicating the spray distance (d1, d2) and / or a system indicating the orientation of the device relative to a reference frame inertial (X0, Y0, Z0), to allow a user to estimate the spray distance with respect to the minimum value and with respect to the maximum value and / or to estimate the orientation of the device with respect to a degree minimal orientation and a maximum degree of orientation. Assembly according to Claim 10, characterized in that the indicator system is mounted on the spraying device or offset relative to the spraying device, the indicator system comprising, for example, a screen configured to be installed against a wall of a spray booth. spray. Assembly according to one of claims 6 to 11, characterized in that the spray device is a device without actuating trigger. Assembly according to one of Claims 6 to 12, characterized in that the spraying device comprises a means of communication with a computer system, capable of transmitting to said computer system, instantaneously or offline, spray information, such as spraying times. A method of pneumatic spraying, implemented by means of a spraying device comprising: a proximity sensor capable of detecting the presence of an object in a detection field, a system for injecting a coating product, a spray air injection system, characterized in that the method comprises the following automated steps, during which: a) the air injection system opens when an object enters the detection field of the sensor, b) the product injection system opens timedly with respect to the air injection system, c) the product injection system closes when the object leaves the detection field of the sensor, d) the air injection system closes timedly with respect to the product injection system. A method of pneumatic spraying, implemented by means of a spraying device comprising: two proximity sensors arranged in such a way that the detection field of one is at least partly contained in the detection field of the other, a system for injecting a coating product, a spray air injection system, characterized in that the method comprises the following automated steps, during which: a) the air injection system opens when an object enters the detection field of any one of the two sensors, b) the product injection system opens when the object enters the detection field of the other sensor, c) the product injection system closes when the object leaves the detection field of any one of the two sensors, d) the air injection system closes when the object leaves the detection field of the other sensor.

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