METHOD AND DEVICE FOR CLEANING A VULCANIZATION MOLD

Abstract

Method for cleaning a vulcanization mould for tyres in a curing press, using a device (1) comprising a collaborative mobile robot (10), incorporating a computer program, said robot comprising an autonomous mobile platform (2) mounted on drive wheels and comprising batteries supplying electricity, a dry ice dispenser (6), sensors for identifying the location of the mould to be cleaned and motors ensuring its displacement between a storage location of the device and the mould to be cleaned and the displacement of an articulated mobile arm (3) of said robot, said robot bearing a nozzle (4) for spraying dry ice from said dispenser, wherein the device comprises means for communication with a control unit.

According to the invention, the control unit sends a mission instruction to said device, which navigates between a storage location and the location of the mould and automatically cleans the vulcanization mould.

Claims

1.-17. (canceled)

18. A method for cleaning a vulcanization mold for tires in a curing press, the method comprising using a device comprising a collaborative mobile robot, incorporating a computer program, the robot comprising an autonomous mobile platform mounted on drive wheels and comprising batteries supplying electricity, a dry ice dispenser, sensors for identifying a location of a mold to be cleaned and motors ensuring the displacement thereof between a storage location of the device and the mould to be cleaned and the displacement of an articulated mobile arm of the robot, the arm bearing a nozzle for spraying dry ice from the dispenser, wherein the device comprises means for communication with a control unit for performing the following operations: after having received a mission instruction to clean a vulcanization mold and after having checked a level of electrical charge of the batteries and a level of dry ice in a tank of the dispenser, leaving the storage location; automatically navigating to the location of the mold to be cleaned; automatically scanning an environment in which the curing press comprising the mold to be cleaned and possible obstacles are located; automatically identifying the curing press comprising the mold to be cleaned and standing in proximity thereto; automatically cleaning the vulcanization mold by directing the arm bearing the spray nozzle, according to a set of instructions, to an interior of the mold so as to clean it with dry ice; and communicating with the control unit to inform of the progress of the cleaning operation.

19. The method according to claim 18, wherein the device communicates with at least one operator.

20. The method according to claim 18, wherein the device communicates with a controller controlling a curing shop in which the curing press comprising the mold to be cleaned is located.

21. The method according to claim 18, wherein the device circumvents the possible obstacles.

22. The method according to claim 18, wherein, after having received information that the cleaning of the vulcanization mold is finished, the control unit sends a new vulcanization mold cleaning mission instruction to the device.

23. The method according to claim 18, wherein, after having identified the curing press comprising the mold to be cleaned, the device connects to an electrical charging outlet and to a compressed air outlet that are contiguous to a plinth of the curing press.

24. The method according to claim 18, wherein the device returns to the storage location as soon as a level of dry ice in the tank falls below a predetermined limit.

25. The method according to claim 18, wherein the device automatically recharges the tank with dry ice.

26. The method according to claim 18 further comprising a step of blowing or sucking cleaning residues.

27. A cleaning device configured to clean a tire vulcanization mold in a curing press, the cleaning device comprising: a collaborative mobile robot incorporating a computer program, the robot comprising an autonomous mobile platform mounted on drive wheels and comprising batteries supplying electricity; a dry ice dispenser linked to a spray nozzle borne by an articulated mobile arm of the robot; motors ensuring displacement between a storage location of the device and a vulcanization mold to be cleaned and displacement of the articulated arm; means for communication with a control unit which transmits to the cleaning device a vulcanization mold cleaning mission instruction; sensors for identifying a location of the mold to be cleaned and a control system using a navigation system, the control system being linked to the sensors to adjust a position of the device and detect the location of the mold to be cleaned and possibly objects in a path of the cleaning device when it moves between the storage location of the device and the location of the mold to be cleaned; a digital data storage memory; and a control module, components of which are actuated according to the vulcanization mold cleaning mission instruction received from the control unit.

28. The cleaning device according to claim 27, wherein the control module comprises a processor which, when it receives a cleaning mission instruction from the control unit, is programmed to: check a level of electrical charge of the batteries and a level of dry ice in the tank; allow the cleaning device to leave the storage location; automatically navigate to the location of the mold to be cleaned; automatically scan an environment in which the curing press comprising the mold to be cleaned and possible obstacles are located; automatically identify the curing press comprising the mold to be cleaned and stand in proximity thereto; automatically clean the vulcanization mold by directing the arm bearing the spray nozzle, according to a set of instructions, to an interior of the mold so as to clean it with dry ice; and communicate with the control unit to inform of the progress of the cleaning operation.

29. The cleaning device according to claim 27 further comprising means for communication with at least one operator.

30. The cleaning device according to claim 27, further comprising means for communication with a controller controlling a curing shop in which the curing press comprising the mold to be cleaned is located.

31. The cleaning device according to claim 27, further comprising navigation means allowing the cleaning device to avoid obstacles.

32. The cleaning device according to claim 27, further comprising means for identifying location with respect to the curing press comprising the mold to be cleaned and means for connecting to an electrical charging outlet and a compressed air outlet that are contiguous to a plinth of the curing press.

33. The cleaning device according to claim 27, further comprising sensors for measuring a level of dry ice in the tank, the sensors being linked to the control system, which sends an instruction to the control module to return the device to the storage location as soon as the level of dry ice in the tank falls below a predetermined limit.

34. The cleaning device according to claim 27, further comprising means for blowing or sucking cleaning residues.

Description

[0050] The invention will be better understood from the rest of the description, which is based on the following figures:

[0051] FIG. 1 is a perspective view of a cleaning device of the invention;

[0052] FIG. 2 is a side view of the device of FIG. 1;

[0053] FIG. 3 schematically illustrates the connection panel of the cleaning device during the cleaning operation;

[0054] FIG. 4 is a functional block diagram of the cleaning device;

[0055] FIG. 5 is an operating diagram of the cleaning device according to a first embodiment of the invention;

[0056] FIG. 6 is an operating diagram of the cleaning device according to a second embodiment of the invention.

[0057] In the different figures, elements that are identical or similar bear the same reference. Their description is not therefore systematically repeated.

[0058] FIG. 1 illustrates a cleaning device 1 capable of cleaning vulcanization moulds for tyres according to the invention. The device 1 comprises a collaborative mobile robot 10 comprising an autonomous mobile platform 2 on which is mounted an articulated arm 3 which bears a spray nozzle 4 linked to a dry ice dispenser and which moves around with the platform. The autonomous mobile platform 2 comprises a chassis 20 of generally rectangular form. The chassis is supported by two pairs of front and rear wheels 22, mounted to rotate freely, and it is displaced by two differential wheels 21, each being driven in rotation by an electric motor. The autonomous mobile platform 20 also incorporates electrical supply batteries (not represented in the drawings). The autonomous mobile platform 2 also comprises sensors for scanning and identifying the environment, a microprocessor control device and means for communicating wirelessly, for example by WiFi with a remote control unit. Such an autonomous mobile platform is for example of the MiR 200 type offered by Mobile Industrial Robots ApS. It can carry up to 200 kg of load, it comprises multiple (ultrasound and laser) sensors and a 3D camera that are incorporated and linked to the microprocessor control unit of the platform. The autonomous mobile platform 20 can thus scan its environment, it identifies obstacles or people, that it manages to avoid, while calculating the most efficient path to get to its destination. The control device of the platform is linked to the embedded control system of the cleaning device, for example by a link of ethernet type.

[0059] The articulated arm 3 is a collaborative robot arm which is mounted on the autonomous mobile platform 2, from which it receives power supply and commands in operation. It goes without saying that the platform incorporates proximity sensors which detect the approach of an operator or of an object. The robot is of the collaborative type and comprises force sensors which act on the collaborative robot accordingly in a manner that is generally known, notably from the document U.S. Pat. No. 9,669,548. The force sensors of the collaborative robot act when the autonomous platform is stopped. The articulated arm 3 is of the collaborative robot type with six axes of rotation and comprises several arm sections that are articulated relative to one another. The last section 31 of the articulated arm 3 comprises an effector 32 which holds the body 41 of a spray nozzle 4 so that the nozzle is displaced with the arm.

[0060] The body 41 of the spray nozzle 4 is extended by a wand 43. The wand 43 is covered by a sleeve 42 made of a material which has good thermal insulation properties, such as insulating wool, expanded polystyrene, etc. The spray nozzle is connected using a flexible pipe (not illustrated in the drawings) to a dry ice dispenser, as will be explained hereinbelow.

[0061] As can be seen better in FIGS. 1 and 2, a frame 5 is fixedly mounted on the top face of the autonomous mobile platform 2. The frame 5 is of metal and forms a supporting structure for certain components of the vulcanization mould cleaning device. The frame 5 comprises a first part 51 supporting the articulated arm 3 and a second part 52 forming a support for other components of the device. The articulated arm 3 is mounted at the front end of the part 51 of the frame 5 by being raised and remotely sited relative to the front end of the mobile platform 2 so as to be able to more easily access the interior of the mould to be cleaned.

[0062] The second part 52 of the frame 5 supports a dry ice dispenser 6 and an embedded control system 7. The dry ice dispenser 6 comprises a tank 61 which contains pellets of dry ice at a temperature of approximately 78 C. The dry ice pellets have a cylindrical form with a diameter of approximately 2 to 3 mm for a height of a few mm. In a variant, microcrystals of dry ice can be used. The pellets or microcrystals of dry ice pass from the tank 61 into a dispensing chamber 62 from which they are sprayed at approximately 300 m/s onto the surface to be cleaned using compressed air. The compressed air at a pressure lying between 1 and 15 bar arrives in the chamber 62 from the compressed air network of the curing shop or from a compressor borne by the autonomous mobile platform 2. In a variant, the chamber 62 is linked to a fan borne by the autonomous platform. The entry into the chamber 62 is provided with a solenoid valve (not illustrated in the drawings) which is controlled by the control system 7 of the device. The tank 61, the chamber 62 and the pipes for transferring dry ice to the spray nozzle 4 are covered with thermal insulating materials.

[0063] The control system 7 of the cleaning device is linked to the control device of the autonomous platform 2, which uses an embedded navigation system. The device comprises, in its memory, a map of the workshop (which can be plotted by the device or downloaded from a digital medium) and is capable of steering and navigating (it calculates its path based on the point of departure, the point of arrival and the obstacles encountered) by using algorithms of SLAM (Simultaneous Localisation And Mapping) type.

[0064] As illustrated in FIG. 4, the control system 7 is linked to the control and navigation device of the autonomous platform 2, which receives the information from the sensors of the device to identify the location of the mould to be cleaned. The control and navigation device is linked to said sensors to adjust the position of the device and detect the location of the mould to be cleaned and possibly the objects to be avoided on its path when it moves between a storage location of the device and the location of the mould to be cleaned. The device also comprises means for communicating wirelessly, for example by WiFi, with a remote control unit 100 which acts as supervisor for operation of the device, a unit which transmits to it a vulcanization mould cleaning mission instruction. The embedded control system 7 is of microprocessor computer type, therefore comprising one or more CPU processor units and RAM and ROM memories. The device also comprises a command module which allows its components to be actuated according to the instruction received from the control unit 100 via the control system 7.

[0065] The cleaning device also comprises a module for communication of GSM type with at least one operator. Each operator is provided with a receiver device of connected watch, tablet or smartphone type. Thus, the operator who is in the curing shop thus receives a message from the device, which is in the process of performing its vulcanization mould cleaning mission and is alerted to the operation in progress in order to be able to take appropriate measures (move away to avoid the noise, leave the workshop, etc.).

[0066] When it is not engaged in a vulcanization mould cleaning mission, the cleaning device stands in a storage location in which it is connected to an electrical recharging terminal (not illustrated in the drawings). The storage location is provided with means for supplying dry ice from a storage tank or from a dry ice production machine.

[0067] When it is engaged in a cleaning mission, the device 1 navigates to the location of the curing press comprising the vulcanization mould to be cleaned and it stands alongside the latter. The plinth of the curing press is provided with an electricity and compressed air supply terminal 8. The supply terminal 8 can be seen better in FIG. 3. It comprises a marker 81 which is a shape recognition marker, the form of the marker having been previously stored in the memory of the cleaning device. The terminal 8 also comprises a compressed air supply outlet 82 and an electricity supply outlet 83. The compressed air connection is made via a rapid pneumatic coupling with instantaneous connection of the type marketed by the company PARKER HANNIFIN. The electricity connection is made using a rapid coupling of the SELFPLUG magnetic coupling type from the company GULPLUG. In operation, the device 1 comes to stand in front of the marker 81, which ensures the accurate positioning of the corresponding outlet for coupling its compressed air connection pipe to the compressed air outlet 82 and its respective electrical connector to the electricity supply outlet 83.

[0068] In a variant, the cleaning device comprises an embedded compressor and carries sufficient electrical energy in its batteries not to need to be connected to the terminal 8.

[0069] In operation, the cleaning device directs the spray nozzle 4 to the interior of the mould to be cleaned in accordance with the instructions received from its control system 7. The dry ice sprayed under pressure against the hot parts of the vulcanization mould to be cleaned provokes, on the one hand, a mechanical shock, through the high speed impact of the ice particles against the walls of the mould and, on the other hand, a thermal shock, through the temperature difference (approximately 170 C. for the hot mould and approximately 78 C. for the dry ice). As a result of the cumulative effects of the mechanical shock and of the thermal shock, the moulding residues detach from the wall of the mould. In addition, the dry ice goes directly from the solid state to the gaseous state, its volume is significantly increased (approximately 800 times), which drives with it a part of the cleaning residues. At the end of the cleaning, the solenoid valve, which allows the dry ice to access the chamber 62, is closed and the nozzle 4 sends compressed air to the mould, which makes it possible to discharge the cleaning residues. In a variant, the arrival of compressed air in the chamber 62 is blocked and the chamber is then connected with a fan which allows suction via the nozzle 4 (the dry ice still being prevented from accessing the chamber by the solenoid valve). The suction action of the fan of the device allows the cleaning residues to be sucked via the nozzle 4 into the chamber 62, which communicates for this purpose with an ancillary storage tank via a non-return valve (not illustrated in the drawings).

[0070] FIG. 5 is a block diagram which illustrates the main steps of the vulcanization mould cleaning operation according to a first embodiment. The cleaning device thus communicates with the control unit of the workshop and performs the operation automatically according to the steps indicated in FIG. 5. This is a fully automatic cleaning operation.

[0071] More particularly and as can be seen in this figure, the cleaning of the vulcanization mould is decided on after the checking of the cured tyre and for the purpose of preventive maintenance requested by the controller controlling the curing shop. The information is transmitted to the control or supervision unit, in this case the controller controlling the curing shop, which calls the cleaning device to perform a vulcanization mould cleaning mission. The device checks the level of dry ice in its tank and the level of charge of its batteries and, if necessary, it recharges, then it leaves the storage location. The device is displaced autonomously to the press N to be cleaned for which it has received the cleaning mission instruction. The device knows the location of the press and calculates its optimum path to get to it in autonomous navigation mode. Having arrived in front of the press, the device connects for compressed air and electricity to the supply terminal provided for that purpose at the foot of the press. Once connected, the device launches the cleaning operation according to a preestablished program and according to data received from the central unit. The mould is thus cleaned, the residues being removed in a blowing or sucking operation performed by the cleaning device. The collaborative mobile robot is then automatically disconnected by the device. The cleaning device returns to its storage location in autonomous navigation mode and awaits a new instruction.

[0072] FIG. 6 is a block diagram which represents the steps of the vulcanization mould cleaning operation according to a second embodiment. The starting point is the step of inspection of the cured tyre, but the order is given this time by an operator, who is the vulcanization mould expert, and who transmits his or her instructions via an interface of the control unit of the device. The cleaning device is displaced autonomously and performs the cleaning automatically, but it communicates with the operator, who intervenes at certain steps before transmitting an instruction to the device. This is a semi-automatic cleaning operation.

[0073] More particularly, and as can be seen in this figure, once the cured tyre has been checked, the vulcanization mould expert is called to check the mould which has performed the curing of the checked tyre and decides to perform a cleaning operation on the mould, either entirely, or only on a part or zone which has produced defects on the tyre. The expert then sends a cleaning mission instruction to the device. As in the mode previously described, the device checks the level of dry ice in its tank and the level of charge in its batteries and, if necessary, it recharges, then it leaves the storage location. The device is displaced autonomously to the press to be cleaned N for which it has received the cleaning mission instruction. The device knows the location of the press and calculates its optimum path to get there in autonomous navigation mode. Having arrived in front of the press, the device stops and the operator connects it for compressed air and electricity to the supply terminal provided for this purpose at the foot of the press. After connection, the expert sends the device an instruction to perform a cleaning program that he or she has chosen after having performed the inspection of the mould. The device performs the cleaning operation. Once the mould has thus been cleaned, the residues are removed by a blowing or sucking operation performed by the cleaning device. The device communicates with the expert to inform him or her of the end of the cleaning. The expert checks the quality of the cleaning performed and disconnects the collaborative mobile robot. The device then returns to its storage location in autonomous navigation mode and awaits a new instruction.

[0074] Other variants and embodiments of the invention can be envisaged without departing from the scope of its claims.

[0075] Thus, instead of an autonomous platform guided using its sensors and a map based on algorithms of SLAM type, it is possible to use an autonomous guided vehicle, known by the acronym AGV, which navigates by following, for example, a magnetic rail or using a radar. Quite apart from the navigation system, which is different, such a cleaning device comprising an autonomous guided vehicle comprises the same components as that previously described.

[0076] It is also possible to provide for the cleaning device to return to its storage location as soon as the control system detects a malfunction of one of its components.