FR2750899A1 - METHOD AND INSTALLATION FOR CLEANING A COATING, FILMING OR DRAGEIFYING MACHINE - Google Patents

Abstract

A method comprising (a) a stripping step during which high-pressure water jets from nozzles (60) on telescopic arms (12) are aimed at the upper portion of the inner surface of a turbine (1) rotating at a constant speed, in such a way that they follow a cycloidal path (C), and the turbine (1) contains a bath (120) for soaking and softening the layer to be stripped, the level of said bath being kept constant by means of a telescopic pipe (13); (b) a step of emptying the bath (120); and (c) a suction step for removing the remaining residual water and waste while the turbine (1) is not in operation, by means of a suction pipe (13a) moved longitudinally along the lower generatrix of the vessel (2) in the space between two blades, and retracted upwards to leave room for the suction blade of an adjacent compartment.

Description

 The invention relates to the technical field of coating and more particularly the cleaning of turbines used to deposit, by coating, a layer of product on a tablet or any other product to be isolated from the environment.

 Traditionally, the coating is carried out by placing a batch of products or tablets, for example, 300 kg, in a machine composed of a rotary tank with rotary axis provided with internal blades, substantially radial, and by driving this tank in rotation. at a speed of the order of 3 to 10 revolutions per minute, at the same time as a ramp, with several nozzles, sprays the coating product in the liquid state and a hot air circuit passes through the wall of the tank to form a fluid bed passing through the mass of the products or tablets, spacing them out, and bringing them to a temperature which promotes coating and drying.

 The control of the time / diffusion rate curves, of the active ingredients contained in the tablets, led the manufacturers to coat the tablets with a microporous gastro-resistant lacquer. This lacquer, part of the family of acrylic or cellulosic resins, has a dry film similar to conventional paints of the same families.

 Its application by spraying inside the coating turbines leads to a part of the volume of lacquer used being applied to the internal walls of the turbines, on the spray canes and booms, on the blades as well as the grids and orifices of the fluidization and heating air circuit.

 The temperature of the mass of the tablets being maintained, in general, between 25 and 400, by the blowing of hot air at 60, the losses of lacquer adhere, like a paint, to the internal metallic surfaces of the tank and to the blades.

 Currently, the cleaning of these machines can only be manual because it requires mechanical disassembly of all the parts and subassemblies linked to the tank, its soaking by bubbling in a mixture of hot water added with chemicals, and, after neutralization, rinses and drying, to a complete reassembly. This cleaning operation is performed at each change of family of tablets to be coated, lasts on average 8 hours, and mobilizes at least two operators to scour the surfaces covered with lacquer.

 A lighter cleaning operation, of approximately 4 hours, is carried out every two to three batches of the same family of tablet, depending on the state of fouling of the tank.

 This cleaning time should be compared to the time necessary to coat a batch of tablets which is between 4 and 5 hours.

 It therefore turns out that, with an acrylic or cellulosic coating, the cleaning time is very important, mobilizes several people, and has a very negative impact on the profitability of the workshop and on the manufacturing costs.

 To these disadvantages, we must add those resulting from the need to treat washing effluents before discharging them into the sewerage network, since they contain chemical agents.

 One of the objects of the present invention is to provide a cleaning method ensuring the complete internal cleaning of a bale wrapper tank, automatically, without any disassembly of these elements, in a reduced time of the order of less an hour, and without any human intervention.

This process includes:
a) a pickling phase during which, on the one hand, high pressure water jets are directed against the upper part of the internal face of the tank, in rotation at constant speed, these jets being emitted by nozzles describing , in the longitudinal median plane of the turbine, a cycloidal trajectory close to the shape of the envelope of the longitudinal profile of the turbine, and, on the other hand, the turbine contains, in the lower part, a hot water bath of soaking and softening of the layer to be stripped, the level of this bath being kept constant, above the level of the blades of the turbine,
b) a turbine emptying phase taking place with the turbine stopped and during which the soaking bath is evacuated,
c) a suction phase for residual water and undrained waste, taking place with the turbine stopped and during which a suction duct is moved longitudinally on the lower generator of the tank, is erased upwards, then is returned to the active position, after rotation of the tank by a fraction of a turn bringing, under this suction duct, a low point of another compartment of the turbine.

 The lacquer adhering to the turbine is stripped all the more easily by the jets of pressurized water that it is softened during its passage through the lower bath.

During the pickling cycle, the combination of the nozzle trajectory with the low speed rotation of the turbine, allows the water jets to sweep the entire internal surface of the turbine, whether it is the tank , blades, other elements, but also to act even in the angles between elements.

 This sweep is carried out several times and exposes all the elements of the turbine.

 The suction phase makes it possible to recover the residual water, but also the lacquer waste which is too large to pass through the perforations of the drainage circuit, constituted by the fluidization air circuit, or which, at the end of drain, stick to the wall of the tank.

 The use of only water from the urban network makes it possible to obtain perfect cleaning, and above all to limit the treatment of washing effluents to the filtration of suspended particles. For certain lacquers, which are particularly resistant, it can nevertheless be envisaged to add additives such as detergents, strippers and even sanitizers to the washing water.

 Preferably, the method comprises, between phase b) of emptying the turbine and phase c) of suction of residual water and waste, at least one additional rinsing phase, accompanied by another emptying phase , these last two phases being identical in their nature to that a) of cleaning and b) emptying of the turbine, but of shorter duration.

 This rinsing can be carried out with water from the urban network, or by demineralized water.

 Advantageously, during the cleaning and rinsing phase, the water supplying the nozzles is at a pressure greater than 120 bars and each jet forms an angle of the order of 7 "relative to the longitudinal axis of the nozzle, and is rotatable around this axis, while cleaning, soaking and rinsing water is at an adjustable temperature from 20 to 85 "C.

 The pressure, temperature and rotation of the jets increase the pickling power and reduce the treatment time.

 Another object of the invention is to provide an installation for the implementation of this method.

To this end, the installation includes:
- a control and command cabinet for the different means and functions,
- a chassis movable between an erasing position, clearing the access opening to the tank, and a working position, in which it is positioned vertically, transversely and longitudinally relative to the access opening of the machine , and wedged in front of it, this chassis bearing:
an arm, upper and telescopic, capable of disappearing into this chassis or projecting inside the turbine, and on the free end of which are articulated, around a transverse horizontal axis, at least two conduits, each of these conduits being connected to a pressurized fluid circuit and provided with an extreme nozzle,
- motor means for pivoting the nozzle-holder conduits in both directions,
- motor means for longitudinally moving, in both directions, the elements of the telescopic arm,
means for coordinating the movements of the telescopic elements with the rotation of the nozzle-carrying conduits, so that the nozzles describe a cycloidal trajectory close to the shape of the envelope of the longitudinal profile of the turbine tank,
- a suction duct, lower and telescopic, which, connected to a suction pump, is composed of at least three sections hinged on each other, and is able to occupy an erasing position, in which it is retracted in the chassis, a position for maintaining the level of the soaking bath, in which its intermediate section projects into the turbine downwards from the tank with the lower section folded against it, and a draining and sucking position, in which the lower section is in the extension of the intermediate section,
- motor means for longitudinally moving the suction duct,
- And motor means for pivoting the lower section on the intermediate section and the intermediate section relative to the upper section of the suction duct.

 With this arrangement, the chassis is brought in front of the turbine opening only during the cleaning phase, so that it completely releases access during the coating operations.

 As soon as the chassis is positioned, the telescopic upper arm enters the turbine at the same time as the suction duct, the intermediate element of which is deployed.

 For pickling, the nozzles are displaced by the combination of the longitudinal displacement of the upper telescopic arm with the rotation of the nozzle-carrying conduits relative to the end section of this arm. This combination of movements gives the nozzles a cycloidal trajectory, more or less flattened, depending on the internal shape of the turbine, and so as to escape the blades of the latter, while always being as close as possible to the wall of the tank for make the most of the power of pressurized water jets. This displacement control of the nozzles makes it possible to adapt their trajectories to all the internal profiles of the turbines, and consequently to use the same installation for machines having different tank profiles.

 Other characteristics and advantages will emerge from the description which follows with reference to the appended diagrammatic drawing representing, by way of example, an embodiment of this installation.

FIG. 1 is a partial side view in section showing, schematically, the installation when the chassis is brought before the opening of a turbine,
FIG. 2 is a side view in vertical section showing, on an enlarged scale, the components of the chassis,
FIG. 3 is a sectional view along III-III of FIG. 2,
Figure 4 is a rear view with partial section showing the elements of the chassis,
Figures 5 to 8 are views similar to Figure 1, respectively during the positioning phase of the suction duct, when positioning the upper arm, in the cleaning phase with maintenance of the bath level, and in the suction phase residual water and waste,
Figure 9 is a functional electrical diagram of the means of command and control of the installation.

 In a known manner, this coating installation comprises a turbine 1, itself composed of a tank 2, of generally cylindrical shape, of circular or polygonal section, and provided with frustoconical ends 2a, 2b, with internal blades 3, visible in FIGS. 1 and 5 to 8, means for guiding in rotation about a horizontal axis and means capable of driving it in rotation, as shown diagrammatically here, these means comprise an electric motor 4, connected by a movement transmission 5 to the rear tubular shaft 6 of the tank 2. This tank 2 is provided with an access opening 7 through which the tablets to be coated are introduced, but also the means carrying the spray nozzles of the lacquer coating.

 Figures let 5 to 8 show that the tubular shaft 6 of the turbine is connected to a duct 8 for evacuating the heating air and fluidizing the mass of tablets, and the water vapors.

 The cleaning installation according to the invention is essentially composed, as shown in FIG. 7, of a frame 10 carrying an upper telescopic stripping arm 12 and a lower suction duct 13.

 In the embodiment shown in the drawing, the chassis 10 is intended to cooperate with several coating turbines and is carried by a carriage 14. This carriage, visible in FIG. 1, is motorized and can therefore travel on a track 11 arranged above a row of turbines. This carriage carries positioning means 15, such as a retractable finger which can cooperate with complementary means 16, such as a keeper carried by the frame 17 of the fixed structure of each turbine, for aligning the longitudinal median plane of the chassis 10 with the longitudinal median plane of the turbine 1.

The carriage 14 carries the various means for supplying the members arranged in the chassis. The connection between the chassis 10 and the carriage 14 is ensured, in the embodiment shown, by two cables 18 unwinding from a motorized winch 19 carried by the carriage and the ends of which are linked to the chassis 10.

 The chassis 10 laterally includes guide means, such as rollers 20, 21, cooperating with the wings of the vertical guide rails 22 forming part of the fixed frame 17 of the installation. Finally, the chassis 10 includes lower stop means 23, capable of cooperating with fixed stops 24 fixed on the rails 22.

 In an alternative embodiment not shown, the chassis 10 is carried by a motorized carriage circulating on the ground and comprises stop means cooperating with complementary means of the fixed frame 17 to position it vertically and laterally relative to the opening of turbine access.

 The telescopic upper arm 12 is composed, as shown diagrammatically in FIG. 9, of an interior section 12a, of an intermediate section 12b, and of an exterior section 12c. Figure 4 shows that these three sections have, in cross section, a rectangular shape. Figures 2 and 3 show that the inner section 1 2a is slidably mounted in the intermediate section 12b, that the latter is slidably mounted in the outer section 12c and that the latter is itself slidably mounted relative to fixed bearings, respectively , rear 26 and front 27 of the chassis 10.

 The means ensuring the longitudinal movements of the inner section 1 2a relative to the intermediate section 12b are constituted by an electric motor 28 driving, by means of a motion transmission 29, by toothed pulleys, and notched belt 29, a nut 30 freely mounted in rotation in a bearing 32 fixed in the rear part of the section 12a. The nut 30 cooperates with a longitudinal screw 33, disposed in the section 12a and the rear end of which is locked in rotation in a support 34 secured to the rear wall 35 of the intermediate section 12b.

 The outer section 1 2c is linked in translation by a flange 36 with the lower strand 37a of a toothed belt 37 circulating between a front drive pulley 38 and rear return pulley 39. The drive pulley 38 is linked in rotation to the shaft output of an electric pulse motor 40.

 As shown in more detail in FIGS. 3 and 4, the means ensuring the displacement in translation of the intermediate section 1 2b comprise two lateral transmissions each composed of two pivots, respectively anterior 42 and posterior 43, projecting laterally from one side of the outer section 12c , and on each of which is freely rotatably mounted a pulley 44 for a toothed belt 45. The upper strand of each belt 45 is linked to the fixed frame 10 by a flange 46, while the lower strand is linked to a flange 47. As shown in FIG. 4, this flange is linked to the corresponding side wall of the intermediate section 1 2b and passes through the wall of the external section 12c by a longitudinal slot 48.

 FIGS. 2 and 3 show that the interior section 12a of the telescopic cleaning arm 12 comprises, substantially at mid-length, a transverse wall 50 carrying a front longitudinal housing 52, at the front end of which a transverse rotary shaft 53 is articulated. Figure 2 shows that this shaft is integral, in rotation with a toothed pulley 54, cooperating with a toothed belt 55, forming part of a movement transmission 56 disposed in the housing 52. This movement transmission comprises several speed reduction stages . It is connected by a toothed belt 57 to the output shaft of an electric pulse motor 58 fixed in the inner section 12a.

 On the shaft 53, at least two conduits 59 are fixed, the free ends of which are provided with rotary nozzles 60, capable of emitting a jet 61 which, as shown in FIG. 7, is inclined relative to the longitudinal axis x ' , x of the nozzle and of the conduit 59, of an angle ~ of the order of 7 to 8 ".

 Each conduit 59 is supplied with pressurized fluid by a circuit 62 which, formed in the axis 53, is itself supplied, through a rotary seal 63, by a rigid conduit 64 extending to the wall 50. At this point, the conduit 64 is connected at 65 to a semi-rigid conduit 66 describing in the chassis 10 an S-shaped trajectory during which it forms a posterior loop and an anterior loop. The posterior loop is delimited by a guide 67, of semi-circular shape, while the anterior loop is delimited by a grooved pulley 68 mounted free in rotation on an axis 69, projecting vertically from a support 70 wedged at the end of the rod 72 of a pneumatic cylinder whose body 73 is linked to the chassis.

 As shown schematically in Figure 9, the suction duct, lower and telescopic 13, is composed of three tubular sections, namely a lower section 13a, an intermediate section 1 3b and an upper section 13c. Furthermore, the entire duct is carried by a slide 74 which can slide relative to the chassis 10.

 Figure 4 shows that the slide 74 has, in cross section, the general shape of a "U" open at the bottom and whose wings 74a rest on longitudinal supports 75 of the chassis. One of the wings is integral with a rack 76 which meshes with a pinion 77? wedged on the output shaft of an electric motor 78.

 As shown in FIG. 2, the slide internally carries a rear fixed bearing 79 and an anterior fixed bearing 80 in which a longitudinal screw 82 is rotatably mounted. This screw is linked in rotation to an electric motor 83 carried by the slide.

 The upper section 1 3c of the suction duct is integral with two nuts 84 which are crossed by the screw 82 and which support this section relative to this screw.

 The intermediate section 1 3b is articulated at the front end of the section 1 3c by an articulation whose axis 85 is linked to the rear end of the section 13b and is secured to a lever 86. This lever is connected, by a connecting rod 87, to the rod 88 of a pneumatic jack whose body 89 is articulated at 90 on the upper section 13c.

 The articulation between the lower section 1 3a and the intermediate section 13b is effected by means of a pin 92 which, integral with the rear end of the section 13a, is mounted to rotate freely in a bearing provided at the front end of the section 13b. This axis 92 is integral with a toothed sector 93 cooperating with a rack 94. The latter is fixed to the end of the rod 95 of a jack whose body 96 is articulated at 97 on the intermediate section 13b.

 The rear end of the conduit 13 is connected to a flexible conduit 98 passing through the chassis 10 and going to a suction pump 99 carried by the carriage 14, (FIG. 1), in passing, with the semi-rigid supply conduits 66 nozzles 60 in pressurized fluid, in an articulated manifold 100, connecting the chassis 10 to the carriage 14.

 FIG. 9 shows that the tank 2 cooperates, on the one hand, with a sensor 102 measuring its speed of rotation and, on the other hand, with a sensor 103 detecting fingers 104 assigned to each of the compartments of the turbine. These two sensors are connected by circuits, respectively 1 02a and 103a, to a cabinet 105 for command and control of the various functions of the cleaning installation.

This cabinet 105 therefore comprises, in addition to an automaton 106 or, in general, data processing means governing the operation of the various organs:
means 107 reacting to the information from the sensor 102 for supplying the electric motor 4 for driving the tank 2, so that this tank has a constant speed of rotation during the blasting phase, whatever the variations in the mass of the treatment bath,
- Means 108 which, connected by circuits, respectively 40a and 58a to the motor 40 for moving the external section 1 2c of the upper arm and 58 for driving in rotation the nozzle-holder conduits 59, coordinate the supply of these motors , so that the trajectory of the nozzles 60 has a cycloidal shape, close to the shape of the envelope of the longitudinal profile of the tank 2 of the turbine.

This wardrobe still has
means 109, connected by circuits 83a and 28a to the motors 83 and 28, for controlling the supply of these motors,
means 110 controlling the supply of the motor 78 for moving the slide 74 of the suction duct 13,
- And distribution means 111 governing the operation of the cylinder 95, 96 for folding the lower section 1 3a of the suction duct, but also of the cylinder 88, 89 for folding the intermediate section 13b.

 These means 110 react to the orders of the control means 106 and cause the folding of the arm 1 3a against the arm 13b, then by a circuit 102b, the supply of the electric motor 4 for driving the turbine in rotation over a fraction of turns , determined by the information coming from the sensor 103. After rotation of a fraction of a turn, the means 110 control the unfolding of the arm 1 3a in the extension of the arm 13b and the supply of the motor 78, so that the conduit fully deployed suction moves longitudinally against the bottom wall of the turbine in an interval between two rows of blades 3.

 Finally, compared with the traditional coating installation, that according to the invention comprises, on the discharge duct 8, an additional duct 112 closed by an oscillating flap 113 (FIG. 1). The duct 112 is equipped with a vacuum cleaner 114 which can provide a flow rate several times greater than one or more fans 115, arranged in the chassis 10 and sending an air flow into the turbine. For example, when the fan or fans 115 flow 1500 m3 / hour, the vacuum cleaner 114 has a flow of 4000 m3 / hour, so as to put the turbine in vacuum and thus avoid any projection by the opening 7 of the turbine outside the turbine, the opening of which is closed in a sealed manner, during the cleaning phase.

 FIG. 3 shows that these sealing means consist of a plate 116 which, carried by the chassis 10, is able to be moved in translation by motor means arranged in the chassis to come into abutment against a circular joint 117 carried by a ring 118. This ring, which is arranged around and without contact with the nose 2c of the tank, is carried by the fixed frame 17.

 To clean the interior of a coating turbine whose spray bars have been removed from the tank 1, it suffices to control, by means of the cabinet 105, the positioning of the chassis 10 in front of the access opening 7 of the corresponding turbine 1. The carriage 14 therefore moves longitudinally then, when it is positioned above the machine, by cooperation of its lock 15 with the keeper 16, the winch 19 allows the chassis to be lowered 10. During this downward movement of the chassis 10 , the latter is guided by its rollers 20, circulating in the vertical rails 22 of the frame 17. At the end of the race, the stops 23 come to bear on the fixed stops 24 of the rails 22. I1 is then proceeded to the sealed closure of the turbine by displacement and plating of the wall 116, against the seal 117 and then at the tilting of the flap 113, which passes from its position shown in FIG. 1, in which it closes the duct 112, to the position shown in FIG. 5, in which it closes the duct 8.

 At this phase of the cycle, the upper telescopic cleaning arm 12 and the lower suction duct 13 are removed. The displacement of the lower duct 13 is achieved by supplying the motor 83 which, by means of the screw 82, causes the longitudinal displacement of the entire duct 13 from the retracted position it previously occupied, (Figure 2) to the position shown in Figure 5, that is to say with the front end of the section 13 c protruding from the chassis 10 and penetrating inside the turbine. The jack 88, 89 is then supplied so as to cause the intermediate section 13b to tilt downward, as shown in phantom in FIG. 5.

 The cleaning arm 12 is brought into the starting position by displacement of the internal section 12a relative to the intermediate section 12b by means of the motor 28 driving the nut 30 cooperating with the screw 33. At the end of this movement, and as shown in FIG. 6, the internal section 12a is sufficiently developed to allow the free pivoting of the nozzle-holder conduits 59. These are moreover pivoted vertically upwards to come into their position for starting cleaning, position in which they are inclined to the horizontal by substantially 20 ".

 Simultaneously with this preparation operation, the tank 2 of the turbine is supplied with water, preferably hot water. There is also formed, in the lower part and up to the level H, shown in FIG. 6, a treatment bath 120. This level, located above the top of the blades 3, is determined so that the lower end of the intermediate section 13b of the suction duct can permanently suck up the overflow.

 Just before the start of washing, the fans and vacuum cleaners 115 and 114 are started, and the turbine 1 is rotated by its motor 4.

 Throughout the duration of the cleaning, the turbine is maintained at a constant speed of the order of 6 revolutions / minute, thanks to the sensor 102 and to the regulation means 107.

 During cleaning, and more precisely the stripping of the upper wall of the tank by the jets 61 emitted by the nozzles 60, the cycloidal path C described by the nozzles is regulated by the means 108 which, under the control of the means 106, control supplying the motors, respectively 40 for moving the external section 12c and for the motor 58 for controlling the rotation of the nozzle holders 59.

 Note that the longitudinal displacement of the outer section 12c is communicated to the intermediate section 1 2b by the two lateral transmissions comprising the belts 45 and the connecting flanges, respectively 46 with the chassis and 47 with the intermediate section.

 The combination of the rotation of the tank at constant speed, of the particular trajectory of displacement of the nozzles 60, of the high speed rotation of the order of 4000 revolutions / minute of the two eccentric jets 61, of the pressure, of the 'of the order of 140 bars, and of the temperature, of the order of 80 C, of the water supplying the nozzles, makes it possible to obtain an effective pickling of the lacquer adhering to the walls of the turbine 1, whether it acts on the wall of the tank 2, the blades 3 and any other protruding element inside the tank. This cleaning is carried out all the more easily since, during the rotation of the tank 2, the internal elements of the latter pass into the soaking bath maintained at constant level by the suction duct, a bath which softens the lacquer and facilitates detachment by pressurized jets. During the washing cycle, the nozzles describe the cycloidal path C several times.

 When the upper arm 12 is extended, the jacks 73 allow their rods 72 to retract to release the necessary length of the semi-rigid conduit 66, by reducing the length of the branches of the loop formed around the pulley 68. When the retraction of this arm, the jacks are supplied so that their rods 72 extend and form a longer loop thereby accumulating the excess length of the corresponding conduit 66.

 This compensation device reduces wear on the ducts and organizes the accumulation of excess duct in the chassis in a simple manner, without generating on this con

 It is then proceeded to the emptying of the lower treatment bath, emptying which is carried out by folding the lower element 13a in the extension of the intermediate element 13b and the suction duct. At the end of the emptying, the arm 13a is again folded back against the arm 13b.

 I1 is then carried out a rinsing operation which is carried out in the same way as the cleaning operation, but which has a shorter duration, of the order of five minutes. At the end of the rinsing, and after emptying the rinsing bath, there is a suction phase of the residual water and lacquer waste too large to be sucked through the suction duct and / or adhering, by their humid character, at the walls of the tank.

 In this phase, and as shown in FIG. 8, the section 1 3a is brought in the extension of the intermediate section 1 3b and the assembly of the duct 13 is moved against the lower part of the tank 2, while stopped, by displacement of the slide 74 relative to the chassis 10, that is to say by supplying the motor 83 driving the screw 82. When the nozzle-like end of the lower section 13 a of the suction duct has gone and back against one of the generators of the tank, this section 1 3a is folded against the section 1 3b and the tank is pivoted a fraction of a turn under the control of the sensor 103, cooperating with the fingers 104. At the end of this rotation, the sucking cycle starts again.

 The use shows that it is enough to repeat this operation 4 to 6 times to rid the tank of all residues and all waste.

 It is specified that, in the case of a tank having a polygonal cross section, that is to say composed of facets, the sucking operation is carried out by stopping the tank so that the receptacle formed by the angle between two facets is at the low point, that is to say either in the lower position, substantially in the vertical median plane of the turbine.

 Advantageously, and to prevent the humidity permeating the upper telescopic arm and the lower supply duct destroying the electronic electrical circuits arranged in the chassis 10, these two elements are then entirely deployed inside the tank and left in this position for a few minutes, so that the ventilation passing through the tank rids these elements of all moisture. After drying, the upper telescopic arm 12 and the lower duct 13 are returned to the erasing position inside the chassis 10 and the entire chassis is in turn brought back to the erasing position above the tank.

 In practice, the entire operation is carried out fully automatically, without any human intervention and requires 45 minutes. It is followed by a hot air drying operation of the turbine, the duration of which is around 30 minutes.

 It appears from the above that the method and the installation according to the invention make it possible not only to rid the personnel of any particularly delicate, tedious and tiring scouring task, but also to divide the cleaning time by six, allowing thus increasing the profitability of the machine.

Claims (17)

 1. Method for cleaning a coating machine, characterized in that it comprises:  a) a stripping phase during which, on the one hand, jets (61) of high pressure water are directed against the upper part of the internal face of the turbine (1), rotating at constant speed, these jets being emitted by nozzles (60) describing, in the longitudinal median plane of the turbine, a cycloidal trajectory (C) close to the shape of the envelope of the internal longitudinal profile of the turbine (1), and, on the other hand , the turbine (1) contains, in the lower part, a bath (120) of soaking water and softening of the layer to be stripped, the level of this bath being kept constant, above the level of the blades (3) of the turbine,  b) a turbine emptying phase, taking place with the turbine stopped and during which the soaking bath (120) is evacuated,  c) a phase of suction of the residual water and of the undrained waste, taking place with the turbine (1) stopped and during which a suction duct (13a) is moved longitudinally on the lower generator of the tank (2 ), is erased upwards, then is brought back to the active position after rotation of the tank (2) by a fraction of a turn bringing, under this suction duct (13a), a low point of another compartment of the turbine.  2. Method according to claim 1, characterized in that it comprises, between phase b) of draining the turbine (1) and phase c) of suction of residual water and waste, at least one phase additional rinsing, accompanied by another emptying phase, these last two phases being identical in their nature to that a) of cleaning and b) emptying of the turbine (1), but of shorter duration.  3. Method according to claim 1, characterized in that, during the cleaning and rinsing phase, the water supplying the nozzles (60) is at a pressure greater than 120 bars and each jet (61) forms with respect to the 'longitudinal axis of the nozzle an angle of about 7 ", and is rotatable about this axis.  4. Method according to claim 1, characterized in that the cleaning, soaking and rinsing water is at a temperature above 80C C.  5. Installation for implementing the method according to any one of claims 1 to 4, for cleaning a coating machine composed of a tank (2) of generally cylindrical shape with frustoconical ends of internal blades (3) projecting substantially radially, from means for guiding the rotation of the tank and from means for driving this tank in rotation, one end of this tank having a cylindrical opening (7) for access to the turbine ( 1), characterized in that it comprises:  - a cabinet (105) for monitoring and controlling the various means and functions,  - a frame (10) movable between an erasing position, clearing the opening (7) for access to the tank (2), and a working position, in which it is positioned vertically, transversely and longitudinally with respect to the opening (7) for access to the turbine (1) and wedged in front of it, this chassis carrying:  - an upper and telescopic arm (12), capable of being erased in this chassis (10) or projecting inside the turbine (1), and on the free end of which are articulated, around an axis horizontal transverse, at least two conduits (59), each of these conduits being connected to a pressurized water circuit and provided with an end nozzle (60),  - motor means (54 to 58) for pivoting the nozzle-holder conduits (59) in both directions,  - motor means (28 and 40) for longitudinally moving, in both directions, the elements (12a, 12b, 12c) of the telescopic arm,  - Means (108) for coordinating the movements of the elements of the telescopic arm (12) with the rotation of the nozzle-carrying conduits (59), so that the nozzles (60) describe a cycloidal trajectory (C) close to the shape of the envelope of the longitudinal internal profile of the turbine tank (2) (1),  - a suction duct (13), lower and telescopic, which, connected to a suction pump (99), is composed of at least three sections articulated on each other (13a, 13b, 13c), and is able to occupy an erasing position, in which it is retracted into the chassis (10), a position for maintaining the level of the soaking bath (120), in which its intermediate section (13b) projects into the turbine (1) towards the bottom of tank (2) with the lower section (12a) folded against it, and a draining and sucking position, in which the lower section (13a) is an extension of the intermediate section (13b),  - motor means (78, 83) for longitudinally displacing the suction duct (13),  - And means (92 to 96, and 86 to 89) for pivoting, respectively, the lower section (13a) on the intermediate section (13b) and the intermediate section (13b) relative to the upper section (12c) of the conduit aspirant (13).  6. Installation according to claim 5, characterized in that it comprises a sensor (102) measuring the speed of rotation of the turbine (1) and reacting on means (107) of constant speed regulation of the drive motor ( 4) of this turbine (1) and a sensor (103) for detecting the angular position of the turbine (1) cooperating with means (104) carried by this turbine (1) for, in the final suction phase, detecting the angular position of the turbine (1), the latter sensor (103) reacting on means (110) supplying the motor (4) driving this turbine to cause the rotation of the turbine over a fraction of turns , with stopping of a low point of the turbine (1), in the lower part and in the longitudinal median plane of this turbine.  7. Installation according to claim 5, characterized in that the upper telescopic arm (12) is composed of an outer section (12c), slidably mounted in the frame (10), of an intermediate section (12b) slidably mounted in the outer section (12c), and an inner section (12a) slidably mounted in the intermediate section (12b) to which it is connected by motor means (28, 29, 30, 32) capable of moving it relative to this intermediate section.  8. Installation according to claim 7, characterized in that the motor means able to move the inner element (12a) of the upper arm (12) comprise a threaded rod (33), wedged in translation and in rotation on the rear wall ( 35) of the intermediate section (12b) of this arm, and a nut (30), mounted for free rotation in a bearing (32) of the inner section and linked in rotation to an electric motor (28) carried by this section.  9. Installation according to claim 7, characterized in that the motor means capable of moving the intermediate section (12b) and the inner section (12a) of the upper arm relative to the chassis (10) comprise, on the one hand, a motor electric impulse (40) driving a toothed belt (37) which, circulating between two pulleys, respectively driving (38) and deflection (39), carried by the chassis (10) above the upper arm, is linked by its lower strand (37a) to the outer section (12c) of the arm (12), and, on the other hand, at least one lateral transmission composed of a toothed belt (45) circulating on two pulleys (44) mounted to rotate freely on the outer section (12c) and one of the strands is linked to the frame (10), while the other strand is linked to the intermediate section (12b).  10. Installation according to claim 5, characterized in that the nozzle-carrying conduits (39), two in number, are fixed to the ends of a transverse shaft (53) which, mounted free in rotation at the free end of the inner section (12a) of the upper arm (12), is integral, in this section, with a toothed pulley (54) connected, by a toothed belt (55) and a reducing transmission (56, 57), to the shaft output of an electric pulse motor (58) carried by this inner section.  11. Installation according to claim 5, characterized in that the upper section (13c) of the suction duct (13) is carried by a slide (74) which, slidingly mounted longitudinally in the frame (10), is integral with at least a rack (76) cooperating with a motorized pinion (77, 78), carried by this chassis (10).  12. Installation according to claim 5, characterized in that the upper section (13c) of the suction duct (13) is integral with at least two nuts (84) carrying it and in which a longitudinal screw (82) is screwed, this screw being mounted free in rotation, in fixed bearings (79, 80) of the slide (74), and connected to an electric motor (83) capable of driving it in rotation.  13. Installation according to claim 5, characterized in that the connection between the intermediate section (13b) and the upper section (13c) of the suction duct (13) is provided by an articulation whose axis (85), linked to the section intermediate (13b), is integral with a lever (86), itself connected, by a connecting rod (87), to the rod (88) of a jack whose body (89) is articulated on the upper section ( 13c).  14. Installation according to claim 5, characterized in that the connection between the lower section (13a) and the intermediate section (13b) of the suction duct (13) is provided by an articulation whose axis (92), linked to the section lower (13a), is integral with a toothed wheel (99) cooperating with a rack (94), said rack being integral with the rod (95) of a jack whose body (95) is articulated on the intermediate section ( 13b).  15. Installation according to all of claims 5 and 9, characterized in that the shaft (53) carrying the nozzle holder conduits (59) is supplied on each side, and with the interposition of a rotating seal ( 63), by a rigid duct (64) which, extending in the lower section (12a) of the arm (12), is connected to a semi-rigid duct (66) describing an S-shaped trajectory in the chassis (10), each semi-rigid conduits passing over a rear guide guide (67), carried by the chassis (10), and over a front pulley (68), carried by the end of a stroke compensation cylinder (72, 73 ), jack fixed on this chassis (10) parallel to the path of the arm (12).  16. Installation according to claim 5, characterized in that the frame (10) carries at least one fan (115) generating an air flow entering the turbine (1), while the turbine is connected to a conduit extraction (112) provided with a vacuum cleaner (114) whose flow rate is greater than that coming from the chassis (10) to generate a vacuum in the turbine (1).  17. Installation according to claim 5, characterized in that the chassis (10) is carried by a movable carriage (14) and comprises positioning means (23) able to cooperate with complementary means (24) carried by a fixed frame (17) disposed in front of each turbine (1).