EP0021986B1 - Device for automatically depositing a pasty substance on a surface and automatic machine therefor - Google Patents

Description

The present invention relates to a device for automatically depositing, on a surface, a pasty substance packaged in a tight and flexible tank.

The invention also relates to an automatic marking machine comprising several of these devices.

The device targeted by the invention is mainly intended for marking various objects, the pasty substance contained in the sealed and flexible tank in this case consisting of ink or paint.

In other applications of the device which is the subject of the invention, this pasty substance may be a grease, an adhesive, a putty or other sealing or sealing products, or else a chemical reagent intended to be deposited on an object.

We know that, in industry, it is often necessary to mark mass-produced parts with dots or lines of ink or paint, to identify the different parts, to identify defective parts or for any other reason.

This marking can be carried out by a marking device comprising a paint refill comprising an outlet orifice through which the paint is expelled when the refill is compressed.

In the patent franCâl5 n ° 2 298 444 of the Applicant, a semi-automatic marking device has been described, in which the refill of paint or ink is fixed, in a removable manner, in a sealed housing connected to a source of 'pressurized air. The outlet of this refill has a nozzle, the end of which carries a shutter valve which can be opened by simple contact with the surface to be marked.

The expulsion of the paint by this valve this shutter is obtained by controlling the introduction of compressed air into the housing to compress the refill, and by placing the end of the nozzle on the surface to be marked to push in and open the valve.

Such a device can be used, to mark automatically, various objects scrolling for example continuously, opposite the outlet nozzle of the refill. To this end, this marking device can be associated with means making it possible to bring it intermittently into contact with the successive objects to be marked.

Experience has shown that such a device is not entirely satisfactory. Indeed, for the marking to be carried out in good conditions and to avoid any deterioration of the shutter valve of the nozzle of the device, the distance between the surface of the objects to be marked and the device must be adjusted in a way very precise. It is often not possible to carry out this adjustment with precision, because the parts to be marked can have variable dimensions, an irregular surface or include roughness or similar defects.

The object of the present invention is to remedy the drawbacks of known embodiments, by creating an automatic device, in particular for marking objects, of very convenient use and which can be used in many fields of industry.

The device targeted by the invention for automatically depositing on a surface a pasty substance packaged in a tight and flexible reservoir comprises a sealed case in which this reservoir is removably disposed, the outlet orifice for the pasty substance from this reservoir being connected to an outlet nozzle comprising at its end a shutter valve which can open by contact with the surface, and the housing being connected to a source of gas under pressure, means being provided for controlling the arrival of this gas inside the housing.

According to the invention, this device is characterized in that the housing comprises a cylinder open at its free end and surrounding the outlet nozzle, a piston made integral with this nozzle and the reservoir, slidably mounted inside this cylinder, in this guedes means are provided to control the sliding of this piston towards the open end of the cylinder, so as to project the outlet nozzle outside the open end of the cylinder, and in that it further comprises means for returning the piston to the housing after the action of compressed gas has ceased.

To deposit the pasty substance on objects, scrolling for example continuously opposite the device, it suffices to control the introduction of pressurized gas into the housing and into the cylinder to cause the compression of the pasty substance reservoir and the sliding of the piston towards the object.

Thanks to this arrangement, the distance between the shutter valve of the tank nozzle and the objects does not need to be adjusted with precision. It suffices that the stroke of the piston is sufficient to allow the valve to touch the object. Furthermore, even if the valve of the nozzle touches the object before the end of the possible stroke of the piston, the valve does not risk any deterioration, thanks to the damping effect exerted by the compressed gas.

According to an advantageous version of the invention, the means for controlling the sliding of the piston comprise means allowing the simultaneous introduction of pressurized gas into the housing and into the cylinder.

The compression of the pasty substance reservoir is thus obtained simultaneously, and the piston slides towards the object.

According to a preferred version of the invention, the aforementioned means consist of a communication between the cylinder and the housing.

This arrangement allows a significant simplification of the device.

Other features and advantages of the invention will appear in the description below.

• - la figure 1 est une vue schématique, en coupe longitudinale et avec arrachements, du dispositif conforme à l'invention placé en regard d'objets à marquer,
• - la figure 2 est une vue analogue à la figure 1, le dispositif étant en cours de fonctionnement,
• - la figure 3 est une vue en coupe longitudinale, avec arrachement, d'un dispositif de marquage associé avec une clef dynamométrique,
• - la figure 4 est une vue en plan de la tête du dispositif selon la figure 3, la clef dynamométrique étant enlevée,
• - la figure 5 représente un dispositif conforme à l'invention monté sur une machine pour marquer des carters de moteurs en plusieurs endroits.

In the appended drawings, given by way of nonlimiting examples:

• FIG. 1 is a schematic view, in longitudinal section and with cutaway, of the device according to the invention placed facing objects to be marked,
• FIG. 2 is a view similar to FIG. 1, the device being in operation,
• FIG. 3 is a view in longitudinal section, with cutaway, of a marking device associated with a torque wrench,
• FIG. 4 is a plan view of the head of the device according to FIG. 3, the torque wrench being removed,
• - Figure 5 shows a device according to the invention mounted on a machine for marking engine housings in several places.

In the embodiment according to FIG. 1, the marking device 1 is mounted on a fixed station on a frame facing a surface 3 on which objects 4 are placed, such as mechanical parts produced in series, intended to be marked with means of the device.

The surface 3 is constituted for example by a conveyor belt moving continuously in the direction of the arrow F.

The marking device 1 comprises a reservoir or tube 5 with a flexible wall containing a pasty marking substance 6, such as a paint or an ink.

This tube 5 is housed in a housing 7 axially surrounding this tube. The tube 5 is fixed to an outlet nozzle 8 for the marking substance 6 carrying at its free end 9 a shutter valve 10. This valve 10 is held in the closed position by a spring 11 housed inside the free end 9 of the nozzle 8. This valve 10 can open by exerting pressure on it in the direction of the arrow F1 (see FIG. 1)

The housing 7 is extended towards the surface 3 by a cylinder 12 having at its free end 13 an opening 14. This cylinder 12 surrounds the outlet nozzle 8 of the tube 6. In this cylinder 12 is mounted, in a sliding manner, a piston 15 of which the outlet nozzle 8 is integral. Between this piston 15 and the free end 13 of the cylinder 12 is inserted a return spring 16.

The interior of the housing 7 communicates with the cylinder 12 through an opening 19 of larger diameter than that of the tube 6. The housing 7 is connected by a tube 17 to a source of compressed air 18. The introduction of air compressed 18 in the housing 7 can be controlled by a valve 20, for example electromagnetic, whose opening and closing can be triggered by a detector 21. This detector 21 triggers the opening of the valve 20 as soon as an object 4 is located opposite the end 9 of the nozzle 8 of the device 1. This detector 21 controls the closing of the valve 20 after a predetermined time, as a function of various parameters, such as the sliding speed of the piston 15 towards objects 4, the speed of scrolling of objects 4, or the nature of the desired marking (in the form of dots or lines). The detector 21 can be, for example, a probe known per se, comprising a lever capable of successively coming into contact with the objects 4 and associated with an electric switch capable of controlling the opening and closing of the solenoid valve 20.

The detector 21 can also be a photoelectric cell sensitive to the presence of objects facing the nozzle 8 and capable of intermittently transmitting electrical signals capable of controlling the opening and closing of the valve 20. The closing of the valve 20 can be triggered by a preset timer according to the above parameters. Furthermore, in the case where the surface 3 moves at a constant speed and where the objects 4 are placed at regular intervals on this surface, the control of the opening and closing of the electromagnetic valve 20 can be ensured by pulses successive using any appropriate means according to the frequency of the successive presentation of the objects 4 opposite the nozzle 8 of the marking device 1.

• Dès qu'on objet 4 se présente en regard de la buse 8 du tube 5, la détecteur 21 déclenche l'ouverture de l'électrovanne 20. Le gaz comprimé 18 introduit dans le boîtier 7 comprime le .tube 5 et pousse en même temps le piston 15 vers l'objet 4. Ce piston 15 comprime le ressort 16 et amène le clapet 10 en contact avec l'objet 4. Le clapet 10 s'ouvre, de sorte que la substance de marquage 6 à l'état comprimé s'échappe de ce clapet 10 et se répand sur l'objet 4. Le contact entre le clapet 10 et l'objet 4 est maintenu pendant toute la durée de l'ouverture de l'électrovanne 20.

The operation of the marking device 1 is as follows (see FIG. 2):

• As soon as object 4 is presented opposite the nozzle 8 of the tube 5, the detector 21 triggers the opening of the solenoid valve 20. The compressed gas 18 introduced into the housing 7 compresses the .tube 5 and pushes at the same time the piston 15 towards the object 4. This piston 15 compresses the spring 16 and brings the valve 10 into contact with the object 4. The valve 10 opens, so that the marking substance 6 in the compressed state s 'escapes from this valve 10 and spreads over the object 4. The contact between the valve 10 and the object 4 is maintained throughout the duration of the opening of the solenoid valve 20.

There is thus obtained, on the object 4, a mark in the form of more or less long dots or lines depending on the preset duration of the opening of the valve 20.

After the preset opening time of valve 20 has expired, the valve closes. The closing of the valve 20 controls the exhaust of the compressed air 18 and the withdrawal of the nozzle 8 inside the cylinder 12 under the effect of the return spring 16.

The distance d between the free end 13 of the cylinder 12 and the object 4 does not need to be adjusted with great precision. It suffices, in fact, that this distance d is less than the possible stroke of the piston 15 to obtain in all cases a contact between the valve 10 and the surface of objects 4, even if they have varying heights or irregular surfaces with roughness or other defects. Furthermore, in the inactive position, the free end 9 of the nozzle 8 is retracted inside the cylinder 12 where it is effectively protected against mechanical shock.

In the embodiment of FIG. 3, the marking device 22 is fixed to the tightening head 24 of a torque wrench 23. The device 22 comprises a sealed housing 25, connected at 26 to a source of compressed air 27. A inside the housing 25 is housed a tube 28 containing a marking substance. The end piece 28a of this tube 28 is screwed into an outlet nozzle 29, the free end 30 of which carries a ball 31 acting as a valve. The housing 25 is fixed in leaktight manner to a cylinder 32 in which is mounted, in a sliding manner, a piston 33 of which the outlet nozzle 29 is integral. Between this piston 33 and the free end 32a of the cylinder 32 is inserted a return spring 34.

The torque wrench 23 comprises a handle 35, the end of which carries a finger 36 perpendicular to the handle and of square section, engaged in a recess 37 of complementary section formed in a lateral arm 38 of the clamping head 24. This clamping head 24 has a cylindrical part 39 screwed onto the free end 32a of the cylinder 32 and a conical part 40, the top of which, located at a certain distance from the free end 30 of the nozzle 29, has an orifice 41 having a section adapted to that of the nut to be tightened (not shown).

The assembly constituted by the handle 35 and the tightening head 24 is rigid as long as the tightening torque exerted on the nut by biasing the handle 35 does not reach the preset value. When this value is reached, the handle 35 can pivot in a manner known per se along the axis XX 'of the finger 36, so that the tightening torque exerted is interrupted. The axis XX 'of the finger 36 is mounted on a support 42 made integral with the lateral arm 38 of the clamping head 24. This support 42 carries a valve 43 which is connected by pipes 44, 45, respectively to the housing 25 and to the compressed air source 27.

The opening and closing of this valve 43 can be controlled by a lever 46 capable of coming into contact with the handle 35 of the torque wrench 23, when this handle 35 pivots about the axis XX ', that is i.e. when the desired tightening torque is reached.

• On engage l'ouverture 41 de la tête de serrage 24 sur l'écrou à serrer, on sollicite le manche 35 dans le sens du serrage de l'écrou jusqu'à obtention du couple de serrage désiré. Lorsque ce couple de serrage est atteint, le manche 35 pivote autour de l'axe XX', entre en contact avec le levier 46 de la vanne 43, ce qui commande l'ouverture de cette dernière. L'air comprimé 27 introduit à l'intérieur du boîtier 25 comprime le tube 28 et pousse simultanément le piston 33 vers l'écrou engagé dans l'ouverture 41 de la tête de serrage 24. Le clapet 31 entre en contact avec l'écrou et s'ouvre en laissant sortire la substance de marquage. Cette substance de marquage se répand ainsi sur l'ecrou. Pour fermer la vanne 43, il suffit de laisser revenir en arrière le manche 35 pour libérer le levier d'actionnement 46 de la vanne 43. Le piston revient alors en arrière sous l'effet du ressort de rappel 34.

The operation of the marking device 22 is as follows:

• The opening 41 of the tightening head 24 is engaged on the nut to be tightened, the handle 35 is urged in the direction of tightening the nut until the desired tightening torque is obtained. When this tightening torque is reached, the handle 35 pivots about the axis XX ', comes into contact with the lever 46 of the valve 43, which controls the opening of the latter. The compressed air 27 introduced inside the housing 25 compresses the tube 28 and simultaneously pushes the piston 33 towards the nut engaged in the opening 41 of the tightening head 24. The valve 31 comes into contact with the nut and opens leaving the marking substance to come out. This marking substance thus spreads over the nut. To close the valve 43, it suffices to let the handle 35 go back to release the actuating lever 46 from the valve 43. The piston then returns back under the effect of the return spring 34.

The advantage of the device 22 shown in FIG. 3 lies mainly in the fact that it makes it possible to mark any nut having been tightened by the torque wrench 23 to the prescribed tightening torque.

Thus, during the subsequent check, any nut not marked by the marking substance contained in the tube 28 of the device 22 will be deemed not to have been tightened to the value of the expected tightening torque.

The device 22 therefore makes it possible to considerably facilitate the control of the tightening of the nuts during the production of parts in large series.

In the embodiment of FIG. 5, there is shown an automatic marking machine making it possible to carry out a simultaneous marking of several colored dots, for example on the caps of engine casing bearings, for the purposes of manufacturing control, or parts assembly.

This machine comprises a frame 50 in the form of a bracket carrying a wheel 51 with ten spokes 52 mounted for rotation along a vertical axis. In the example shown, each spoke carries six markers, in accordance with the invention 53. For clarity, these markers have been shown only on two opposite spokes The wheel 51 with spokes 52 rotates by tenth of a turn, for example by means of a hydraulic control jack, so as to successively present the spokes 52 opposite the successive casings 54 which pass on the horizontal support 55.

Each spoke or arm 52 receives a low pneumatic pressure (0.5 to 1 bar) for pressurizing the paint refills of the various markers 53 and the descent of the pistons of the latter on the housing to be marked 54.

The pneumatic control and servo-control equipment is advantageously housed in the frame 50.

This machine makes it possible to automatically make either six points of the same color by assigning each spoke 52 of the wheel 51 to this color, or six points of different colors, cachun markers 53, of a color being arranged in a different order on each radius 52 of wheel 51.

Of course, the invention is not limited to the examples which have just been described, and we can make numerous modifications to it without departing from the scope of the present invention.

Thus, the device according to the invention can also be used to deposit on a surface a pasty substance different from a paint or an ink, such as a grease, an adhesive, a sealant, or a chemical reagent, in order to carry out repetitive operations of continuous lubrication, gluing, chewing and others.

The device according to the invention can be attached to any tool performing a determined function on an object, and comprising means for controlling the supply of pressurized gas into the housing and the sliding of the piston towards the object, when the function of the tool on this object is completed.

• A l'aide de moyens de mise sous pression indépendants des moyens de mise sous dépression de l'intérieur du boîtier, on fait coulisser vers l'avant le piston 15 ou 33 et on plonge l'extrémité libre 9 ou 30 du dispositif dans un récipient de faible hauteur contenant de la substance pâteuse, jusqu'à ce que le clapet 10 ou 31 touche le fond du récipient et s'ouvre.

The housing 7 of the device 1 or the housing 25 of the device 22 could also be connected to a vacuum source in order to be able to reload the tube 5 or 28 in pasty substance, in the following manner:

• Using pressurization means independent of the means for depressurizing the interior of the housing, the piston 15 or 33 is slid forward and the free end 9 or 30 of the device is immersed in a container of low height containing pasty substance, until the valve 10 or 31 touches the bottom of the container and opens.

The interior of the housing 7 or 25 is placed under vacuum, which has the effect of expanding the flexible walls of the tube 5 or 28, and causing the aspiration of the marking substance inside this tube 5 or 28 .

Claims (11)

1. Device for automatically depositing, on a surface, a pasty substance packaged in a fluid-tight and flexible reservoir (5), said reservoir being removably fixed in a fluid-tight housing (7), the outlet orifice from this reservoir for the pasty substance being connected to an outlet nozzle (8) including at its free end a cut-off valve (10) which can be opened by contact with the surface, said housing (7) being connected to a source (18) of pressurized gas and means being provided to control the admission of this gas into the housing, characterized in that said housing (7) comprises a cylinder (12) open at its free end and surrounding the outlet nozzle, a slidably mounted piston (15) made fast to said nozzle and said reservoir (5) inside said cylinder (12), means (18, 20, 17) provided to control the sliding of said piston towards the open end (13) of said cylinder, so as to cause the outlet nozzle (8) to project outside the open end of the cylinder, and comprising also means (16) for returning said piston (15) into said housing (7) after the cessation of the action of the pressurized gas.

2. Device according to claim 1, characterized in that the means for controlling the sliding of the piston (15) comprise means enabling the simultaneous introduction of pressurized gas into the housing (7) and into the cylinder (12).

3. Device according to claim 2, wherein said means are constituted by a communication (19) between the cylinder (12) and the housing (7).

4. Device according to any one of claims 1 to 3, characterized in that the return means comprise a spring (16) inserted between the piston (15) and the open end (13) of the cylinder (12).

5. Device according to any one of claims 1 to 4, designed to deposit a pasty substance on a series of articles (4) moving past the open end of the cylinder at a certain distance (d), characterized in that the device is mounted at a fixed station and that it comprises means (21) for controlling the admission of pressurized gas into the housing (7) and the sliding of the piston (15), when an article (4) is presented facing the open end (13) of the cylinder.

6. Device according to claim 5, designed to deposit spots of pasty substance on said articles, characterized in that said means act through successive impulses, according to the frequency of presentation of the articles opposite the device.

7. Device according to claim 5, designed to deposit a continuous line of pasty substance on a surface, characterized in that said means act for a predetermined duration corresponding to the length of the continuous line to be deposited on the surface.

8. Device according to any one of claims 1 to 7, characterized in that it is fixed to a tool (23) performing a predetermined function on an article, said tool comprising means for controlling the admission of pressurized gas into the housing and the sliding of the piston towards the article, when the operation of the tool for this purpose is completed.

9. Device according to claim 8, characterized in that the open end of the cylinder of the device (22) is fixed removably to a tool (23) to tighten a nut or the like, said tool cooperating with means (43) for controlling the admission of pressurized gas into the housing (25) and the sliding of the piston (33) towards the nut or the like, when the tightening of the latter is completed.

10. Device according to claim 9, characterized in that said tool (23) is a torque wrench whose end is fixed removably to a tightening head (24) for a nut, said head (24) being made fast to the open end (32a) of the cylinder (32) of the device (22), said head (24) including facing the valve (31) of the outlet nozzle (30) and at a certain distance from the latter, a tightening recess (41) adaptable to the nut to be tightened, and the torque wrench (23) including a handle (35) which can actuate the control means (43), for the admission of pressurized gas into the housing (25) and the sliding of the piston (33) towards the nut, when the required tightening torque is reached.

11. Automatic marking machine, comprising several devices according to any one of claims 1 to 7, said machine comprises a wheel (51) with several spokes (52) rotatably mounted on a frame (50) on a vertical axis, each spoke (52) bearing several marking devices (53), means being provided to bring the various spokes (52) successively opposite the articles (54) to be marked moving beneath these spokes, so as to continue with the simultaneous marking of several spots on said articles (54).

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