Method for removing the inner rubber from a tire with spreading of the tire sidewalls.

Abstract

The invention relates to a method for removing the inner rubber from a tire, the method being implemented in a removal device comprising a tire gripping device and an abrasive tool mounted at the end of an articulated and automated arm. The removal method involves moving both sidewalls of the tire outwards by a non-zero distance from their unstressed position during a pass of inner rubber removal performed with the abrasive tool. Abstract figure: No figure

Description

Title of the invention: Method for removing the inner rubber from a tire with separation of the tire sidewalls.

[0001] The present invention relates to the recycling of the inner rubber layer located inside a tire, also called the inner rubber. This inner rubber layer is made from a rubber compound comprising one or more relatively expensive components. More specifically, the invention relates to the operation of removing and collecting this inner rubber layer in powder form from end-of-life tires that are no longer usable on vehicles and are intended to be dismantled and recycled, for example, by pyrolysis. Advantageously, the inner rubber powder thus collected can be used directly to manufacture a new inner rubber compound. Only the inner rubber powder can be used to produce a new inner rubber compound.Indeed, a powder extracted from another part of a tire would not produce a sufficiently airtight compound. This direct reuse in a new compound stems from the fact that the inner rubber layer of a tire is not exposed during tire use and is therefore protected from the various contaminants and chemical attacks experienced by the tire's exterior. To give you an idea, the inner rubber layer is 1 to 3 mm thick.

[0002] Document WO2020261090 describes a method and device for removing a layer of self-sealing material from inside a tire. Unlike the sealant layer inside a tire, this layer of self-sealing material is not structurally part of the tire; it is a product added after the tire's manufacture and designed to automatically seal any hole or cut that causes a puncture. This self-sealing material is very viscous and therefore difficult to remove. Document WO2020261090 describes a removal device comprising a device for applying a cryogenic fluid to solidify the self-sealing material, and an articulated arm at the end of which are a tool for removing the self-sealing material solidified by mechanical abrasion and a suction circuit for the pieces of solidified self-sealing material generated by the abrasive tool.

[0003] In the removal device described in document WO2020261090, the pneumatic tire is positioned vertically during the removal of the self-sealing material, i.e., with its axis of rotation horizontal and with its sides substantially parallel to a plane vertical.

[0004] Document CN107855300 relates to a device for cleaning the inner cavity of a newly manufactured tire. The purpose of this cleaning is to remove impurities from the tire manufacturing process that could impair the tire's performance or integrity. This cleaning device comprises a rotating cleaning wheel inside the tire and a cleaning agent diffuser inside the tire.

[0005] In the cleaning device described in document CN107855300, the tire is positioned vertically during the cleaning of the internal cavity of the tire.

[0006] US3953942 relates to cleaning the inner surface of a tire and removing irregularities in rubbery material and mold release agent residues that could cause imbalances during tire use and rotation. The removal device described in US3953942 comprises a rotating abrasive tool mounted at the end of an articulated, automated arm.

[0007] In document US3953942, the tire is positioned vertically during the cleaning of the inner surface of the tire and the abrasive tool is driven in rotation around an axis parallel to the longitudinal direction of the tire and perpendicular to the transverse direction of the tire.

[0008] None of the aforementioned documents aims to remove the sealing rubber layer located inside end-of-life tires for recycling. Therefore, none of the removal devices described in these documents are perfectly suited for this use.

[0009] The present invention has as its primary objective to provide a device and a removal method which are perfectly suited to the removal and collection of the inner rubber of tires in the form of powder.

[0010] Another objective of the invention is to enable the safe collection of the inner rubber in powder form. Indeed, depending on the abrasive tool used and the machining parameters used with this tool, the inner rubber can burn or the removal of the inner rubber can generate very fine particles, for example, smaller than 200 µm, which could locally create an explosive atmosphere in the workshop or factory where the inner rubber removal is carried out.

[0011] Another objective of the invention is to improve and facilitate the recovery of the internal rubber dust for subsequent reuse. Indeed, depending on the abrasive tool used and the machining parameters used with this tool, the internal rubber dust can clog the suction circuit and form aggregates. glomerates preventing its direct reuse in a new inner gum mixture.

[0012] Another objective of the invention is to enable the most direct and straightforward reuse possible of the inner rubber in powder form for the production of a new rubber compound. For example, the invention aims to avoid removing any other material from the tire that is not inner rubber.

[0013] Another objective of the invention is to allow the removal of a maximum amount of inner rubber inside the tire, in particular in a maximum width of the inner surface of the tire.

[0014] Finally, the invention also aims to enable the treatment of tires that are deformed and that do not have a perfectly regular inner surface, particularly in a radial direction with respect to the central axis of the tire.

[0015] To this end, the invention relates to a method for removing the inner rubber from a tire, the method being implemented in a removal device comprising a tire gripping device and an abrasive tool mounted at the end of an articulated and automated arm.

[0016] According to the invention, the removal process provides that the two sidewalls of the tire are moved outwards by a non-zero distance from the position they occupy without stress during a removal pass of the inner rubber carried out with the abrasive tool.

[0017] Advantageously, but not necessarily, the removal process according to the invention may also provide that: - the abrasive tool has a circular cross-section, and that this abrasive tool is driven in rotation around a rotation axis perpendicular to the transverse direction of the tire during a pass of inner rubber removal performed with the abrasive tool, - The abrasive tool is driven in rotation by a motor at a speed between 2000 and 15000 rpm, - The removal process involves detecting a loss of adhesion between the device used to drive the rotating tire and the rotating tire itself. - The abrasive tool has an outside diameter between 70 and 125 mm, - The cutting width of the abrasive tool is between 10 and 30 mm, preferably between 15 and 25 mm. - The abrasive tool moves against the inner surface of the tire and in the transverse direction of the tire during a pass to remove the inner rubber layer performed with the abrasive tool. - the abrasive tool makes a helical pass against the inner surface of the pneumatic, - two consecutive turns of the abrasive tool against the inner surface of the tire overlap by 5 to 15 mm, - the tire is rotated around its central axis during a pass to remove the inner rubber layer, performed with the abrasive tool. - the tire is rotated at a speed between 2 and 20 rpm around its central axis during a pass to remove the inner rubber layer performed with the abrasive tool, - with the tire held in a horizontal position during a pass of inner rubber removal performed with the abrasive tool, the abrasive tool performs a pass of inner rubber removal by moving from top to bottom against the inner surface of the tire.

[0018] The invention also relates to a device for removing the inner rubber from a tire, the removal device comprising a tire gripping device and an abrasive tool mounted at the end of an articulated and automated arm.

[0019] According to the invention, the gripping device for holding the tire in a horizontal position, with its sides substantially parallel to a horizontal plane, during the removal of the inner rubber with the abrasive tool, the gripping device allows the two upper and lower sides of the tire to be moved respectively upwards and downwards by a non-zero distance from the position they occupy without stress during the removal of the inner rubber with the abrasive tool.

[0020] Advantageously, but not necessarily, the invention may also provide that: - the removal device includes a device for rotating the tire around its central axis, - the rotation device takes the form of a continuous belt driven in rotation between two rollers, or of a motorized toothed roller, or of one or more upper and / or lower tire gripping elements in the form of motorized fingers rotating around their longitudinal central axis.

[0021] Other features and advantages of the invention will become apparent from the following description. This description, given by way of example and not limitation, refers to the accompanying drawings in which: - [Fig. 1] represents an installation for removing the inner rubber from a tire according to the invention, - [Fig.2] represents a device for removing the inner rubber from a tire according to the invention, ready to receive a tire to be treated, - [Fig. 3] represents a device for removing the inner rubber from a tire according to the invention, with a tire ready to be processed in its device. grasping, - [Fig. 4] represents a device for removing the inner rubber from a tire according to the invention, with a tire undergoing treatment. - [Fig. 5] represents the lower gripping elements of a device for removing the inner rubber of a tire according to the invention, - [Fig.6] represents an abrasive tool and a device for adjusting the depth of cut of this abrasive tool of a device for removing the inner rubber of a tire according to the invention, - [Fig.7] represents the spirals of one pass of an abrasive tool of a device for removing the inner rubber of a tire according to the invention, - [Fig.8] represents an abrasive tool and a device for controlling the thickness of the inner rubber removed by the abrasive tool from a device for removing the inner rubber of a tire according to the invention, - [Fig.9] schematically represents in side view a device for controlling the thickness of inner rubber removed by the abrasive tool of a device for removing the inner rubber of a tire according to the invention.

[0022] The invention relates to a method and device for removing the inner rubber from a tire.

[0023] A device 10 for removing the inner rubber from a tire P according to the invention is illustrated in [Fig. 1]. Ideally, this removal device is part of a complete installation for removing the inner rubber from a tire. For example, this installation includes a receiving device 12 for the tires to be treated, located upstream of the removal device 10, and an extraction device 14 for the treated tires, located downstream of the removal device 10. For example, the receiving device and the extraction device include one or more conveyor belts 16. This receiving device 12 and this extraction device 14 facilitate the handling of the tires to be treated or treated by the removal device 10, since the invention is particularly aimed at the treatment of end-of-life heavy-duty tires.For example, for the safety of the operator(s), the removal device 10 and the receiving and extraction devices are installed inside a protective enclosure (not shown), for example, made of wire mesh walls. If provided, this protective enclosure includes an inlet opening for the tires to be treated and an outlet opening for the treated tires. The inlet opening provides access to the receiving device 12 for the tires to be treated, and the outlet opening provides access to the extraction device 14 for the treated tires. Advantageously, the receiving device allows the tires P to be received in a horizontal position and transported in a horizontal position to the removal device 10. Similarly, the device... Extraction device 14 allows the treated tires to be received in a horizontal position from the removal device 10 and evacuated in a horizontal position. The horizontal position of a tire P, as illustrated in [Fig. 1], is a position in which its two sidewalls are substantially parallel to a horizontal plane.

[0024] Figure 2 shows a removal device 10 according to the invention, ready to receive a tire P to be processed. For this purpose, this removal device 10 includes receiving means 18 adapted to receive the tire P to be processed. These receiving means 18 allow the tire P to be positioned centrally within the removal device 10 in a longitudinal direction DL corresponding to the direction of movement of the tires between the receiving device and the extraction device. Preferably, the longitudinal direction DL is horizontal. Positioning the tire P centrally in the longitudinal direction DL by the receiving means 18 allows the tire P to be subsequently grasped. Preferably, the receiving device 12 or the removal device 10 includes a sensor (not shown) for detecting the passage of a tire P into the inlet of the removal device.The information transmitted by this sensor is used by the receiving means 18 to position the tire P to be processed in the central position within the removal device 10 in the longitudinal direction DL. For example, the receiving means 18 take the form of two parallel conveyor belts, right 20D and left 20G, arranged horizontally and spaced apart. The space between the right 20D and left 20G conveyor belts allows for the installation of part of the tire P gripping means of the removal device according to the invention.

[0025] For example, the removal device 10 comprises a parallelepiped-shaped frame 24 consisting of a horizontal platform 26 mounted on four vertical supports 28. The frame 24 is intended to be fixed to the ground via its vertical supports 28. Preferably, the right-hand conveyor belts 20D and left-hand conveyor belts 20G of the receiving means 18 are mounted inside the frame 24 on a main support 30 that is movable in vertical translation on the frame 24 of the removal device. Guiding means, such as guide rails and guide pads, and vertical translation drive means, such as a jack, are provided between the main support 30 and the frame 24 of the removal device.

[0026] Preferably, the receiving device 12 for the tires to be treated includes initial centering means (not shown) for positioning a tire P to be treated in a central position in a transverse direction DT perpendicular to the longitudinal direction DL. For example, these centering means take the form of two guide rails mounted so as to gradually converge towards each other.

[0027] As shown in Figures 3 and 4, a device for removing the inner rubber of a tire comprises a gripping device 22 of the tire P to be treated and an abrasive tool 32 mounted at the end of an articulated arm 34 and automated.

[0028] HORIZONTAL POSITION AND GRIP

[0029] In the method of removing the inner rubber from a tire according to the invention, the tire P is preferably held in a horizontal position, with its sides substantially parallel to a horizontal plane, during the removal of the inner rubber with the abrasive tool 32. Also, as shown in Figures 3 and 4, the gripping device 22 preferably allows the tire P to be held in a horizontal position, with its sides substantially parallel to a horizontal plane, during the removal of the inner rubber with the abrasive tool 32.

[0030] In more detail, the gripping device 22 includes upper elements 36 for gripping the tire and lower elements 38 for gripping the tire P. The upper gripping elements 36 allow the upper sidewall of the tire to be gripped in a horizontal position and the lower gripping elements 38 allow the lower sidewall of the tire to be gripped in a horizontal position.

[0031] Preferably, the upper 36 and lower 38 tire-gripping elements take the form of gripping fingers movable between a deployed position allowing the gripping of a tire sidewall and a retracted position allowing the tire to be released. In [Fig. 2], the gripping fingers forming the upper 36 and lower 38 tire-gripping elements are in the retracted position and therefore not visible. In Figures 3 and 4, the gripping fingers forming the upper 36 and lower 38 tire-gripping elements are in the deployed position allowing the gripping of a tire sidewall. For example, the gripping fingers forming the upper 36 and lower 38 tire-gripping elements P are rotationally movable between their deployed and retracted positions.The gripping fingers forming the upper 36 and lower 38 gripping elements, for example, have a conical shape with a rounded free end. Since the tire P is preferably rotated about its central axis during the removal of the inner rubber, the gripping fingers forming the upper 36 and lower 38 gripping elements are mounted to rotate freely about their respective central axes. Preferably, the gripping fingers forming the upper 36 and lower 38 gripping elements bear against the lower area of ​​the tire sidewalls where the reinforcing bead is located. Advantageously, this lower area of ​​the tire sidewalls, against which the upper 36 and lower 38 gripping elements bear, is an area of ​​the tires at the end of their service life that is less damaged than other parts of the tire. pneumatic, such as the tread for example.

[0032] SPACING OF THE FLANGES

[0033] In the method of removing the inner rubber according to the invention, and for example in the case where the tire is held in a horizontal position during the removal of the inner rubber, the two upper and lower sidewalls of the tire P are preferably respectively moved upwards and downwards by a non-zero distance from the position they occupy without stress during the removal of the inner rubber with the abrasive tool.

[0034] Also, the gripping device 22 allows the upper and lower sidewalls of the tire to be moved upwards and downwards respectively by a non-zero distance from their unstressed position during the removal of the inner rubber with the abrasive tool. For this purpose, the lower gripping elements 38 of the tire are, for example, mounted on the main support 30, which is mounted to move vertically on the frame 24 of the removal device. Thus, with the upper sidewall of the tire held by the upper gripping elements 36, these lower gripping elements 38 allow the two sidewalls of the tire to be moved outwards from their unstressed position during a pass of inner rubber removal performed with the abrasive tool.

[0035] Preferably, the lower gripping elements 38 are mounted on an intermediate support 40, illustrated in [Fig. 5], which is movably vertically on the main support 30. The lower gripping elements 38 are also movably rotated between their extended and retracted positions on this intermediate support 40. Slots 39 provided in the intermediate support 40 allow the lower gripping elements 38 to be fully accommodated in the retracted position. Vertical translational guidance means, such as guide columns, and translational drive means, such as cylinders, are provided between the intermediate support 40 and the main support 30. Similarly, actuators, such as quarter-turn cylinders, are provided to drive the lower gripping elements 38 in rotation relative to the intermediate support 40.

[0036] For example, the lower gripping elements 38 are also mounted to move in translation in a vertical direction relative to the intermediate support 40. More precisely, the lower gripping elements 38 are mounted to move in vertical translation over a distance of 1 to 10 centimeters relative to the intermediate support 40. Thus, when the main support 30 is lowered with the intermediate support 40, and while the lower gripping elements 38 are resting on the lower part of the tire sidewall, these lower gripping elements 38 translate upwards relative to the intermediate support 40 and allow the sidewall to be moved away from the pneumatic intermediate support 40. Thus, the lower sidewall of the tire is no longer in contact with the intermediate support 40, which prevents friction between the lower sidewall of the tire and the intermediate support 40 when the tire is rotated for the removal of the inner rubber with the abrasive tool 32.

[0037] Preferably, the upper gripping elements 36 are mounted on an upper support (not visible in the figures) fixedly mounted on the frame 24 of the retraction device. The upper gripping elements 36 are also mounted to rotate between their deployed and retracted positions on this upper support. Slots provided in the upper support allow the upper gripping elements 36 to be fully retracted. Actuators, such as quarter-turn cylinders, are provided to rotate the upper gripping elements 36 relative to this upper support.

[0038] For the purpose of receiving a tire P to be processed, and as shown in [Fig. 2], the main support 30 is in a lower position relative to the frame 24 of the removal device, the intermediate support 40 is in a lower position relative to the main support 30, and the upper gripping elements 36 and lower gripping elements 38 are in a retracted position. The tire P to be processed is received by the right conveyor belts 20D and left conveyor belts 20G of the receiving means 18. By being in its lower position relative to the main support 30, the intermediate support 40 frees up the available space between the right conveyor belts 20D and left conveyor belts 20G for receiving a tire P to be processed.

[0039] Next, in a first step of gripping the tire P to be treated, the intermediate support 40 is brought into a high position relative to the main support 30 and the lower gripping elements 38 are driven in rotation towards their deployed position to grasp the lower sidewall of the tire P to be treated.

[0040] In a second gripping step of the tire P to be processed, the main support 30 is moved vertically upwards so as to bring the upper sidewall of the tire P within reach of the upper gripping elements 36, and the upper gripping elements 36 are rotated to their deployed position to grasp the upper sidewall of the tire. Preferably, the removal device 10 includes a sensor 42, for example a contact sensor, for detecting the upper sidewall of the tire P to be processed. This sensor 42 stops the upward translation of the main support 30 at the correct position so that the upper gripping elements 36 can grasp the upper sidewall of the tire P.

[0041] In a third important step of the process according to the invention, with the upper 36 and lower 38 gripping elements in the deployed position and retaining the two sidewalls of the tire P to be treated, the main support 30 is driven into A downward vertical translation is performed to move the two sidewalls of the tire P outwards from their unstressed position. Indeed, in the method of removing the inner tread of a tire according to the invention, the two sidewalls of the tire are displaced outwards by a non-zero distance from their unstressed position during a pass of the inner tread removal performed with the abrasive tool. These outward displacements of the tire sidewalls are illustrated in Figures 3 and 4. For example, the upper and lower sidewalls of the tire P are each displaced from 10 cm to 30 cm from their unstressed position. In [Fig. 3], the abrasive tool 32 has not yet been inserted into the tire to be treated.

[0042] In a fourth step illustrated in [Fig. 4], the abrasive tool 32 was brought into contact with the inner surface of the tire P and the inner rubber GI of this tire by means of the articulated arm 34. Preferably, the abrasive tool 32 and the articulated arm 34 are introduced inside the tire P after the sidewalls of the tire have been moved outwards from their unstressed position, and thus separated from each other. This gives the articulated arm 34 more space and freedom of movement to bring the abrasive tool 32 into contact with the inner surface of the tire P.

[0043] ARTICULATED ARM

[0044] In order to introduce the abrasive tool 32 into the tire P to be treated and to extract it from the tire once the inner rubber removal operation is complete, the articulated arm is mounted to move vertically TV relative to the frame 24 of the removal device and to rotate about a horizontal pivot axis AP. Furthermore, at its lower end, the articulated arm 34 includes a lateral arm 44 extending substantially perpendicularly to the main body 46 of this articulated arm 34. The abrasive tool 32 is mounted at the end of this lateral arm 44. This lateral arm 44 allows the abrasive tool 32 to be offset laterally from the main body 46 of the articulated arm 34 by several tens of centimeters.Thus, the abrasive tool 32 can reach the inner rubber GI located just under the tread of the tire P without the main body 46 of the articulated arm 34 coming into contact with the tire P.

[0045] In more detail, the articulated arm 34 is pivotally mounted about the pivot axis AP on a carriage 48, and this carriage 48 is mounted to move vertically TV relative to the frame 24 of the removal device. An actuator combined with guiding means, such as an electric linear table, drives the carriage 48 in vertical translation TV relative to the frame 24 of the removal device. The rotation of the articulated arm 34 relative to the carriage 48 is controlled by a cylinder 50 whose body is mounted via a pivot joint on the carriage 48, the end of whose rod is connected by a pivot joint to the upper end of the articulated arm 34. The pivot axis AP of the articulated arm is located between its lower end, where the abrasive tool 32 is mounted, and its upper end, to which the rod of the cylinder 50 is connected. This cylinder 50 brings the abrasive tool 32 into contact with the inner surface of the tire P and controls the application pressure of the abrasive tool 32 against the inner surface of the tire. By controlling the application pressure of the abrasive tool 32 against the inner surface of the tire, the cylinder 50 also controls the depth of cut of the abrasive tool 32 into the inner rubber layer.Preferably, this cylinder 50 is pneumatic in order to allow the articulated arm 34 to behave as an air suspension and to allow the abrasive tool 32 to follow the positive or negative deformations of the used tires, these used tires having in particular defects in cylindricity.

[0046] This arrangement and kinematics of the articulated arm 34 allows the abrasive tool 32 to be brought as close as possible to the sides of the tire in order to collect a maximum quantity of inner rubber in each used tire treated according to the invention.

[0047] Advantageously, the lateral arm 44 of the articulated arm 34 can be equipped with an upper roller 52 on its upper side and a lower roller 54 on its lower side. These two rollers prevent potential damage in the event of contact between the lateral arm 44 and the tire, for example when the abrasive tool 32 removes the inner rubber as close as possible to the sidewalls of the tire P.

[0048] ABRASIVE TOOL AND MACHINING STRATEGY

[0049] In the present invention, and with a view to facilitating the reuse of the inner rubber extracted from used tires, the abrasive tool 32 makes it possible to remove the inner rubber GI in the form of a powder having a particle size between 100 and 400 micrometers. For this purpose, this abrasive tool 32 has a granular, highly rough, or rasp-like and / or irregular abrasive outer surface 56. For example, this abrasive outer surface 56 is made of metal or an abrasive composite material. For example, the abrasive outer surface 56 of the abrasive tool 32 has a grain size selected from the P12 to P30 indices used in the ISO 6344 family of standards.

[0050] Preferably, and as illustrated in [Fig. 6], the abrasive tool 32 has a circular cross-section, and the removal method according to the invention provides that this abrasive tool 32 is driven in rotation about a rotation axis AM perpendicular to the transverse direction of the DTP tire during a pass of removing the inner rubber performed with the abrasive tool. For example, the abrasive tool 32 is driven in rotation by a motor at a speed between 2000 and 15000 rpm. For example, this abrasive tool 32 has an outside diameter between 70 mm and 125 mm.

[0051] The application pressure of the abrasive tool 32 against the inner surface of the tire defines the cut width of the abrasive tool 32. Since the width of a tire's tread is several tens of centimeters, this cut width is, for example, between 10 and 30 mm, preferably between 15 and 25 mm. Therefore, the removal process according to the invention provides that the abrasive tool 32 moves against the inner surface of the tire and in the transverse direction of the DTP tire during a pass of the inner rubber removed by the abrasive tool. Thus, the abrasive tool 32 sweeps across the entire width of the tire's inner surface, from one sidewall to the other.

[0052] Preferably, the removal process according to the invention provides that the abrasive tool 32 makes a helical pass against the inner surface of the tire. Thus, a tire P can be treated in a single pass. In order to collect a maximum amount of inner rubber GI, and as schematically illustrated in [Fig. 7], the removal process according to the invention provides that two consecutive turns S1, S2, ... of a pass of the abrasive tool 32 against the inner surface of the tire overlap by a distance of 5 to 15 mm.

[0053] For example, in order to obtain this helical machining path of the abrasive tool 32 inside the tire P, the method according to the invention preferably provides that the tire P is rotated about its central axis AC during a pass of removing the inner rubber performed with the abrasive tool. For this purpose, the removal device 10 includes a device for rotating the tire P about its central axis AC. For example, the tire P is rotated at a speed of between 2 and 20 rpm about its central axis AC during a pass of removing the inner rubber performed with the abrasive tool.

[0054] In a first embodiment shown in [Fig. 2], this rotation device 58 takes the form of a continuous belt 60 driven in rotation between two rollers 62, at least one of the two rollers being motorized. Since the tire P is preferably held in a horizontal position by the gripping device 22 during the removal of the inner rubber, the rotation device 58 is preferably mounted vertically. In a vertical direction, this rotation device 58 is mounted between the upper 36 and lower 38 gripping elements of the tire P. Thus, the continuous belt 60 can come into lateral contact with the tread of the tire. More precisely, the rollers and the continuous belt 60 are mounted on one side of the frame 25 of the removal device 10.

[0055] In a second, unillustrated variant, the tire rotation device may take the form of a motorized, toothed roller. This toothed roller and The motorized toothed roller is preferably mounted vertically. Preferably, this motorized toothed roller is mounted vertically between the upper 36 and lower 38 gripping elements of the tire P. This allows the motorized toothed roller to come into contact with the tire tread and rotate it. For example, this motorized toothed roller is mounted on one side of the frame 25 of the removal device 10.

[0056] In a third variant not illustrated, the rotation device could consist of one or more upper 36 and / or lower 38 gripping elements for the tire P. For this purpose, the upper 36 and / or lower 38 gripping element(s) used for rotating the tire take the form of motorized fingers rotating around their longitudinal central axis.

[0057] Advantageously, in the present invention, when the tire P is driven in rotation around its central axis AC for the removal of the inner rubber, the tire P is only held in position by the upper gripping elements 36 and the lower gripping elements 38.

[0058] In parallel with the rotation of the tire during the removal of the inner rubber, the removal process according to the invention may include the detection of a loss of adhesion between the device used to drive the rotating tire and the rotating tire. For example, this detection can be implemented by comparing the rotational speed of one of the rollers 66 with the speed of the belt 60 or any other device used to drive the rotating tire. This detection is important because a loss of adhesion can alter the trajectory of the abrasive tool 32 and lead to an increase in the depth of cut of the tool, resulting in a risk of removal of the layer located under the inner rubber.

[0059] In addition to the rotation device 58, the removal device 10 includes a tire centering device 64 for the tire during the removal of the inner rubber. This centering device 64 takes, for example, the form of two parallel centering rollers 66 mounted freely for rotation. This centering device 64 is preferably mounted vertically, like the rotation device 58. This centering device 64 is also mounted between the upper 36 and lower 38 gripping elements of the tire P. Thus, the centering rollers 66 can come into lateral contact with the tire tread. More precisely, the centering rollers 66 are mounted on the side of the frame 24 opposite to the side where the rotation device 58 is located.

[0060] The tire P being preferably held in a horizontal position during a pass of removing the inner rubber performed with the abrasive tool 32, the removal process according to the invention provides that the abrasive tool 32 performs a pass of removing the The inner rubber GI is moved from top to bottom against the inner surface of the tire. This facilitates the collection of the inner rubber GI dust under the treated tire in a horizontal position and under the abrasive tool 32.

[0061] SUCTION

[0062] In order to collect the inner rubber GI removed from the tire by the abrasive tool 32, the removal process according to the invention provides that the inner rubber removed in powder form by the abrasive tool is aspirated from inside the tire in the vicinity of the abrasive tool 32. For example, the inner rubber powder is aspirated to within ten centimeters of the abrasive tool 32. Also, the removal device 10 includes a suction nozzle 68 mounted on the articulated arm 34 in the vicinity of the abrasive tool 32, and for example mounted less than ten centimeters from the abrasive tool 32. More specifically, this suction nozzle 68, visible in [Fig. 6], is fixed to the lateral arm 44 of the articulated arm. As illustrated in Figures 1 and 6, this suction nozzle 68 is connected to a suction unit 70 via a first suction conduit 72 which can include different portions of different sections, flexible or rigid.In addition to collecting the inner rubber in powder form, the suction nozzle 68 also prevents a potentially dangerous cloud of fine inner rubber particles from forming inside the treated tire during the removal of its inner rubber. The suction unit 70 includes, in particular, a reservoir for collecting the inner rubber powder and a device that generates a suction flow.

[0063] In addition to the suction provided inside the tire, the removal method according to the invention also provides that the inner rubber removed in powder form by the abrasive tool is suctioned outside the tire and near at least one sidewall. For example, the inner rubber powder is suctioned to within ten centimeters of at least one sidewall of the tire. To this end, the removal device 10 includes at least one suction nozzle that can be positioned near at least one sidewall of the tire, and for example, can be positioned less than ten centimeters from at least one sidewall of the tire. Advantageously, the removal method according to the invention can also provide that the inner rubber removed in powder form by the abrasive tool is suctioned outside the tire and near both sidewalls of the tire.In this case, the removal device 10 comprises two suction ports (not shown) located on either side of the two sides of the tire.

[0064] In the case where the tire is held in a horizontal position during the removal of the inner rubber, this suction nozzle 68 is preferably installed under the abrasive tool 32, directly under the fall of the inner rubber powder. By being positioned under the abrasive tool 32, this suction nozzle 68 allows the collection of the dusting of inner rubber that has accumulated on the lower sidewall of the tire, particularly at the end of the inner rubber withdrawal cycle.

[0065] Still assuming that the tire P is held in a horizontal position during the removal of the inner rubber, the removal method according to the invention also provides that the inner rubber, removed in powder form by the abrasive tool 32, is suctioned from under the tire P, which is held in a horizontal position. For this purpose, the removal device 10 includes a suction inlet 74 located under the tire P in a horizontal position. For example, this suction inlet 74 is mounted on the main support 30, which is movably mounted vertically on the frame 24 of the removal device. For example, and as shown in [Fig. 5], the suction inlet 74 is integrated into the intermediate support 40 on which the lower gripping elements 38 are mounted. This suction inlet 74 is also connected to the suction unit 70 via a second suction conduit 76, which may include different sections of varying cross-sections, flexible or rigid.This suction inlet 74 also prevents a potentially dangerous cloud of fine particles of inner rubber from forming near the treated tire during the removal of its inner rubber.

[0066] CLEANING

[0067] Optionally, in addition to the dust extraction system located near the abrasive tool 32, the removal process according to the invention may also include cleaning the abrasive tool 32 by blowing compressed air. This cleaning aims to remove any residue from the inner rubber of the abrasive tool 32. This cleaning is preferably carried out during the removal of the inner rubber, but it can also take place before and / or after the removal operation to start with a clean abrasive tool 32 and / or to leave the abrasive tool 32 clean for processing another tire. For the implementation of this compressed air blow cleaning, the removal device 10 includes at least one compressed air blow nozzle 75 connected to a compressed air supply circuit and mounted on the articulated arm 34 near the abrasive tool 32, and in particular fixed to the lateral branch 44 of the articulated arm, so as to direct its flow of compressed air towards the abrasive tool 32.Preferably, the removal device 10 comprises at least two compressed air blow nozzles 75 connected to a compressed air supply circuit and mounted side by side on the articulated arm 34 near the abrasive tool 32, and in particular fixed to the lateral arm 44. Preferably, the two nozzles emit parallel airflows, one after the other, around the abrasive tool 32. For example, the nozzle(s) 75 are mounted less than ten centimeters from the abrasive tool 32. Advantageously, when compressed air blow cleaning is carried out during the removal of the inner rubber with the abrasive tool 32, the compressed air flow(s) allow... It also cools the abrasive tool 32. Another advantage is that compressed air blowing prevents the formation of small clumps of internal rubber dust inside the tire. Preferably, and to avoid the creation of a cloud of fine internal rubber particles, air blowing cleaning is only carried out if a vacuum system is in place simultaneously, near the abrasive tool and / or the sidewall(s) of the tire.

[0068] CONTROL OF PASS DEPTH AND TOOL WEAR

[0069] An objective of the invention is to avoid removing materials other than the inner rubber GI from the tire P, in order to allow immediate reuse of the inner rubber powder. In particular, it is necessary to prevent the abrasive tool 32 from digging into the layer of material located beneath the inner rubber layer.

[0070] To this end, the removal device 10 includes an adjustment device 78 for the depth of cut of the abrasive tool 32, allowing adjustment of the thickness of inner rubber removed by the abrasive tool 32 during a pass of this abrasive tool against the inner surface of the tire, and allowing the abrasive tool 32 to follow the deformations of the inner surface of the tire as the abrasive tool 32 moves relative to the inner surface of the tire to perform a pass of removal of the inner rubber of the tire. In the removal process according to the invention, the inner rubber of the tire is preferably removed in a single pass, for example in a helical pattern.Therefore, and in order to limit the risk of removing material other than the inner rubber, the depth of cut of the abrasive tool 32, set using the adjustment device 78, is 0.2 to 0.4 mm less than the actual thickness of the inner rubber in the treated tire. The actual thickness of the inner rubber in the treated tire can be determined before carrying out the other steps of the removal process according to the invention by various methods. A first manual method can consist of taking a sample of material from the tire to be treated and directly measuring the actual thickness of the inner rubber. Another, more automated method can consist of using a terahertz wave non-destructive testing device to determine the actual thickness of the inner rubber.

[0071] As illustrated in Figures 6 and 9, this depth-of-cut adjustment device 78 takes the form of an element that comes into contact with the inner surface of the tire upstream of the abrasive tool 32 when this abrasive tool 32 moves relative to the inner surface of the tire to perform a pass removing the inner rubber of the tire. In the present invention, the forward movement of the abrasive tool 32 relative to the inner surface of the tire is preferably and primarily obtained by rotating the tire around its central axis AC.

[0072] For example, the depth-of-cut adjustment device 78 takes the form of a roller 80 mounted for rotation at the end of a roller support 82 mounted on the lower end of the articulated arm 34, and in particular fixed to the lateral arm 44 of the articulated arm. Advantageously, and in order to be able to adjust the distance D between the contact point PC of the roller 80 with the inner surface SI of the tire and the cutting point PA of the abrasive tool 32, the position of the roller support on the articulated arm 34 is adjustable, for example, statically and manually or, for example, dynamically and automatically. The cutting point PA of the abrasive tool is the point at which the abrasive tool penetrates the inner rubber most deeply during a pass to remove the inner rubber.The outer profile of the rolling roller 80 corresponds to the outer diameter of the abrasive roller 32 or is preferably set back from this outer profile. In other words, every outer point of the rolling roller 80 is located at a radial distance from the central axis AC of the tire that is at most equal to, and preferably less than, the radial distance at which the cutting point PA of the abrasive tool is located relative to the central axis AC of the tire. Thus, the abrasive tool 32 maintains the same depth of cut even if the inner surface of the tire is curved.

[0073] In order to monitor the wear of the abrasive tool 32, the removal device 10 includes a control device 84 for measuring the thickness of inner rubber removed by the abrasive tool 32 during a pass of this abrasive tool against the inner surface of the tire. As illustrated in Figures 8 and 9, this control device 84 takes the form of a measuring sensor 86 mounted on the lower end of the articulated arm so as to be located downstream of the abrasive tool when this abrasive tool 32 moves relative to the inner surface of the tire to perform a pass removing the inner rubber of the tire. The control device 84 takes the form of a non-contact measuring sensor or one that comes into contact with the inner surface SI of the tire, which has been stripped of a given thickness of inner rubber after the passage of the abrasive tool.Knowing its position relative to the attack point PA of the abrasive tool 32 and allowing its distance from the inner surface SI to be measured after the abrasive tool 32 has passed, this measuring sensor 86 makes it possible to measure the actual thickness ER of GI removed from the tire P by the abrasive tool 32. For example, the measuring sensor 86 is a laser beam distance measuring sensor F, a pro-filometer, a camera, an inductive sensor, or an incremental encoder distance measuring sensor. For example, the measuring sensor 86 is mounted on the end of the articulated arm 34, and in particular fixed to the lateral arm 44 of the articulated arm.

[0074] The removal method according to the invention provides for the use of a removal device 10 comprising a depth-of-cut adjustment device 78 for the abrasive tool 32 allowing adjustment of the thickness of inner rubber removed by the abrasive tool during a pass of this abrasive tool against the inner surface of the tire, and allowing the abrasive tool 32 to follow the deformations of the inner surface of the tire as it moves relative to the inner surface of the tire to perform a pass of inner rubber removal. Furthermore, if the removal device 10 also includes a control device 84 for measuring the thickness of inner rubber removed by the abrasive tool during a pass of this abrasive tool against the inner surface of the tire, the removal process provides for adjusting, manually or automatically, the depth of cut of the abrasive tool 32 according to the measurement taken by the control device 84.

[0075] OTHER FEATURES AND ADVANTAGES

[0076] Advantageously, the removal device 10 according to the invention can comprise several abrasive tools mounted on the same articulated arm 34, or several articulated arms 34 at the ends of which one or more abrasive tools 32 are mounted. For example, a removal device 10 according to the invention comprises two articulated arms 34 mounted symmetrically with respect to each other on the frame 24, each of these articulated arms being equipped with an abrasive tool 32 and being able to be equipped with the adjustment device 78 for the depth of cut of the abrasive tool and the control device 84 for the thickness of inner rubber removed by the abrasive tool.

[0077] By adjusting various machining parameters of the process according to the invention such as for example the rotation speed of the tire and the particle size of the abrasive tool 32, the collected internal rubber powder is not sticky, does not clog the abrasive tool 32 and can be vacuumed without clogging the suction ducts and without it re-agglomerating in mass in the collection container.

[0078] By adapting the abrasive capabilities, including the roughness and / or the manufacturing material, of the abrasive tool 32 to the characteristics of the inner rubber to be removed, the removal process and device according to the invention make it possible to collect a powder of inner rubber having a particle size between 100 and 400 micrometers and therefore directly reusable in the preparation of a new inner rubber compound. Advantageously, they also make it possible to avoid a subsequent step aimed at reducing the particle size of the collected inner rubber.

[0079] By removing the inner rubber in the form of a powder having a particle size between 100 and 400 micrometers, the abrasive tool 32 can create a cloud of inner rubber powder particles.

[0080] The horizontal position of the tire allows this cloud of internal rubber dust particles to be concentrated in the center of the tire and above the suction inlet 74 located under the tire. Advantageously, the internal rubber dust particles fall by gravity towards the suction inlet 74. located under the tire.

Claims

Demands

1. A method for removing the inner rubber from a tire, the method being implemented in a removal device (10) comprising a tire gripping device (22) and an abrasive tool (32) mounted at the end of an articulated arm (34) and automated, the method being characterized in that the two sidewalls of the tire are displaced outwards by a non-zero distance from the position they occupy without stress during a pass of removing the inner rubber carried out with the abrasive tool.

2. A method for removing the inner rubber from a tire according to claim 1, wherein the abrasive tool (32) has a circular cross-section, and wherein this abrasive tool is driven in rotation about a rotation axis (AM) perpendicular to the transverse direction of the tire (DTP) during an inner rubber removal pass performed with the abrasive tool.

3. A method for removing the inner rubber from a tire according to claim 2, wherein the abrasive tool (32) is driven in rotation by a motor at a speed between 2000 and 15000 rpm.

4. A method for removing the inner rubber from a tire according to claim 2 or 3, wherein the removal method provides for detecting a loss of adhesion between the device used to drive the rotating tire and the rotating tire.

5. Method for removing the inner rubber from a tire according to any one of the preceding claims, wherein the abrasive tool (32) has an outside diameter between 70 and 125 mm.

6. A method for removing the inner rubber from a tire according to any one of the preceding claims, wherein the width of the pass of the abrasive tool (32) is between 10 and 30 mm, preferably between 15 and 25 mm.

7. Method for removing the inner rubber from a tire according to any one of the preceding claims, wherein the abrasive tool (32) moves against the inner surface of the tire and in the transverse direction of the tire (DTP) during one pass of removing the inner rubber made with the abrasive tool.

8. Method for removing the inner rubber from a tire according to claim 7, wherein the abrasive tool (32) makes a helical pass against the inner surface of the tire.

9. Method for removing the inner rubber from a tire according to the re- demand 8, in which two consecutive turns (S1,S2,...) of a pass of the abrasive tool (32) against the inner surface of the tire overlap by 5 to 15 mm.

10. A method for removing the inner rubber from a tire according to any one of the preceding claims, wherein the tire is rotated about its central axis (AC) during an inner rubber removal pass performed with the abrasive tool.

11. Method for removing the inner rubber from a tire according to claim 10, wherein the tire (P) is rotated at a speed between 2 and 20 rpm around its central axis (AC) during an inner rubber removal pass performed with the abrasive tool.

12. A method for removing the inner rubber from a tire according to any one of the preceding claims, wherein, the tire being held in a horizontal position during a pass of removing the inner rubber made with the abrasive tool, the abrasive tool (32) makes a pass of removing the inner rubber by moving from top to bottom against the inner surface of the tire.

13. Device for removing the inner rubber of a tire, the removal device comprising a gripping device (22) for the tire and an abrasive tool (32) mounted at the end of an articulated arm (34) and automated, the removal device being characterized in that, the gripping device allowing the tire to be held in a horizontal position, with its sidewalls substantially parallel to a horizontal plane, during the removal of the inner rubber with the abrasive tool (32), the gripping device allows the two upper and lower sidewalls of the tire to be moved up and down respectively by a non-zero distance from the position they occupy without stress during the removal of the inner rubber with the abrasive tool.

14. Device for removing (10) the inner rubber of a tire according to claim 13, wherein the removal device (10) includes a device for rotating (58) the tire (P) around its central axis (AC).

15. A device for removing (10) the inner rubber of a tire according to claim 14, wherein the rotation device (58) takes the form of a continuous strip (60) driven in rotation between two rollers (62), or of a motorized toothed roller, or of a or several upper (36) and / or lower (38) pneumatic gripping elements (P) taking the form of motorized fingers rotating around their longitudinal central axis.

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