Process and plant for producing tyres for vehicle wheels

Abstract

A plant and a process for producing tires wherein the process includes the steps of: a) building a green tire on a toroidal support in a building line of a tire production plant; b) transferring the green tire and the relevant toroidal support from the building line of the production plant to a first holding unit; c) transferring the green tire and the relevant toroidal support from the first holding unit to a vulcanization line of the production plant; d) molding and vulcanization the green tire in the vulcanization line of the production plant; e) separating the molded and vulcanized tire from the relevant toroidal support; f) transferring the toroidal support, separated from the relevant tire, from the vulcanization line to the first holding unit; and g) transferring the toroidal support, separated from the relevant tire, from the first holding unit to the building line of the production plant, wherein steps b) and g) are carried out through a first transfer device and steps c) and f) are carried out through a second transfer device different from the first transfer device.

Claims

1. A plant for producing one or more tyres for vehicle wheels comprising: a building line, for a green tyre on a toroidal support, comprising: a plurality of work stations for building the green tyre; and a cooler for said toroidal support; a vulcanization line for the tyre comprising: a vulcanization unit for the tyre; and a mounter/dismounter for said toroidal support; a first holding unit operatively arranged between said building line and said vulcanization line; a first transfer device to transfer said toroidal support from said first holding unit to said building line and vice-versa and said first transfer device comprising a robotized arm; a second transfer device to transfer said toroidal support from said first holding unit to said vulcanization line and vice-versa and said second transfer device comprising a robotized arm; and a track on which said first transfer device and said second transfer device are movable, wherein the first holding unit is arranged on the track and said first transfer device translates on the track between said first holding unit and said building line and vice-versa, and said second transfer device translates on the track between said first holding unit and said vulcanization line and vice-versa, wherein said first transfer device is adapted for: transferring the green tyre on the toroidal support from the building line to the first holding unit; transferring the toroidal support, separated from the green tyre, from the first holding unit to the cooler of the building line; transferring the toroidal support, separated from the green tyre, from the cooler of the building line to a work station of the building line; and wherein said second transfer device is adapted for: transferring the green tyre on the toroidal support from the first holding unit to a vulcanization unit of the vulcanization line; transferring, after vulcanization, the moulded and vulcanized tyre on the toroidal support from the vulcanization unit to the mounter/dismounter of the vulcanization line; and transferring the toroidal support, separated from the moulded and vulcanized tyre, from the mounter/dismounter of the vulcanization line to the first holding unit.

2. The plant for producing tyres for vehicle wheels according to claim 1, further comprising a second holding unit adapted for holding the green tyre and the relevant toroidal support coming out from the building line and for holding the toroidal support, separated from the relevant tyre, coming out from the vulcanization line.

3. The plant for producing tyres for vehicle wheels according to claim 2, wherein said first transfer device is adapted for: transferring the green tyre and the relevant toroidal support from said second holding unit to the first holding unit; transferring the toroidal support, separated from the relevant tyre, from the first holding unit to the cooling unit of the building line of the production plant; and transferring the toroidal support, separated from the respective tyre, from the cooling unit of the building line to the second holding unit.

4. The plant for producing tyres for vehicle wheels according to claim 1, wherein the vulcanization line comprises two vulcanization units.

5. The plant for producing tyres for vehicle wheels according to claim 4, wherein the vulcanization line comprises two mounters/dismounters.

6. The plant for producing tyres for vehicle wheels according to claim 5, wherein the building line comprises four coolers.

7. The plant for producing tyres for vehicle wheels according to claim 1, wherein said track extends between the cooler and a work station of the building line.

8. The plant for producing tyres for vehicle wheels according to claim 1, wherein said track extends between at least two units selected from a vulcanization unit, a mounter/dismounter, a cooler and a second holding unit.

9. The plant for producing tyres for vehicle wheels according to claim 8, wherein the track extends between the cooler and the second holding unit.

10. The plant for producing tyres for vehicle wheels according to claim 8, wherein said track extends between the vulcanization unit and the mounter/dismounter.

11. The plant for producing tyres for vehicle wheels according to claim 1, wherein said track extends between a work station of the building line and a unit selected from a vulcanization unit, a mounter/dismounter, a cooler, and a second holding unit.

12. The plant for producing tyres for vehicle wheels according to claim 1, further comprising a driver to move the first transfer device and the second transfer device along said track.

13. The plant for producing tyres for vehicle wheels according to claim 1, wherein said vulcanization unit comprises a vulcanization wheel on which six vulcanization moulds are mounted.

14. The plant for producing tyres for vehicle wheels according to claim 1, wherein said first holding unit comprises two seats for housing said toroidal support.

15. The plant for producing tyres for vehicle wheels according to claim 14, wherein said first holding unit comprises four seats capable of housing said toroidal support.

16. The plant for producing tyres for vehicle wheels according to claim 1, wherein said first holding unit is movable.

17. The plant for producing tyres for vehicle wheels according to claim 1, wherein said first holding unit is movable along the track.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) Further characteristics and advantages of the invention shall become clear from the following description of some preferred examples of processes and plants for producing tyres according to the invention, madefor indicating and not limiting purposeswith reference to the attached drawings, in which:

(2) FIG. 1 shows a schematic lay-out of a plant for producing tyres for vehicle wheels in which the process according to the present invention is carried out;

(3) FIG. 2 shows a schematic plan view of a plant for producing tyres for vehicle wheels according to a first embodiment of the invention during a step of the subject process;

(4) FIG. 3 shows a schematic plan view of a plant for producing tyres for vehicle wheels according to a second embodiment of the invention during a step of the subject process; and

(5) FIGS. 4 and 5 show two partial plan views of a plant for producing tyres for vehicle wheels.

DETAILED DESCRIPTION OF THE INVENTION

(6) With reference to FIGS. 1-3 a plant for producing tyres for vehicle wheels according to the present invention through which the production process according to the present invention is carried out is generally indicated with 1.

(7) The plant 1 comprises a building line 2, in which each tyre is built by assembling structural components according to a predetermined sequence, and a vulcanization line 3, in which each green tyre is moulded and vulcanized, within a respective vulcanization mould, thus transforming itself into the finished product.

(8) The building line 2 comprises a plurality of working stations 10 preferably arranged along a closed loop path indicatively represented by the arrows 11 in FIG. 1.

(9) Preferably, said working stations 10 operate simultaneously with each other, each on at least one tyre, to assemble at least one of its structural components thereon.

(10) It should be noted that in the present description and in the subsequent claims by structural component of the tyre it is meant any component selected for example from: liner, sub-liner, carcass ply/plies, sub-belt insert, belt strips either crossing over one another or at zero degrees, attachment sheets for the tread band, tread band, rim, bead filler, textile or metallic reinforcement inserts, anti-abrasion insert, or any portion thereof.

(11) In particular, during the assembly step the various structural components used in making each tyre are advantageously engaged on a toroidal support the shape of which substantially reproduces the internal configuration of the tyre to be obtained. Such a toroidal support is preferably of the type that is collapsible or dismountable into a plurality of sectors, as for example described in document WO 01/62481 to the Applicant, so as to be able to be easily removed from the tyre when processing is completed.

(12) Transfer devices 12 operate in the building line 2 to transfer each of the tyres being processed associated with a respective toroidal support sequentially from one of the working stations 10 to the next working station, so as to determine the sequentially assembly of all the components of the tyre.

(13) Preferably, such transfer devices 12 comprise one or more robotized arms associated with at least one of the working stations 10 and operating on the individual toroidal supports to carry out the transfer in sequence of each tyre being processed.

(14) The building line 2 comprises, preferably, at least one cooling unit 6 of a toroidal support adapted for carrying a toroidal support coming out from the vulcanization line 3 at the suitable temperature to begin a new building process of a green tyre.

(15) A first holding unit 7 of a toroidal support associated with or separated from a respective tyre being processed is operatively arranged between the building line 2 and the vulcanization line 3 of the production plant 1 so as to create a buffer between the two lines.

(16) The production plant 1, according to the present invention, is also provided with a first transfer device R1, to transfer said toroidal support associated with or separated from a respective tyre being processed, between the first holding unit 7 and the building line 2, and with a second transfer device R2, to transfer said toroidal support between the first holding unit 7 and the vulcanization line 3.

(17) Preferably at least one from said first transfer device R1 and said second transfer device R2 comprises a robotized arm.

(18) Preferably, at least one from said first transfer device R1 and said second transfer device R2 is movable on at least one rail 9.

(19) The vulcanization line 3 comprises at least one vulcanization unit 4 of the green tyre, and at least one mounting/dismounting unit 5 in which the vulcanized and moulded tyre is separated from the respective toroidal support.

(20) in the first embodiment of the production plant 1, shown in FIG. 2, the vulcanization line 3 comprises a vulcanization unit 4 and an mounting/dismounting unit 5.

(21) In the second embodiment of the production plant 1, shown in FIG. 3, the vulcanization line 3 comprises two vulcanization unit 4 and an mounting/dismounting unit 5.

(22) Each vulcanization unit 4 comprises a number of vulcanization moulds adapted for the production capacities of the production plant 1. In particular, in the embodiments shown in FIGS. 2-5, each vulcanization unit 4 comprises six vulcanization moulds.

(23) Preferably, the vulcanization moulds are mounted on a turntable to be driven in rotation so as to make the same vulcanization moulds carry out a closed-loop path, sequentially carrying them, one after the other, to a tyre loading/unloading station, each associated with its own toroidal support.

(24) In this way, a green tyre, after having been loaded into a vulcanization mould, is subjected to a moulding and vulcanization process and, once the suitable time to complete the moulding and vulcanization operations has been achieved, is unloaded from the mould at the same loading/unloading station through rotation of the turntable.

(25) The vulcanization moulds are preferably sealed airtight and are arranged to house a tyre being processed previously built on a toroidal support, the outer surface of which substantially reproduces the internal configuration of the tyre to be obtained. Said vulcanization moulds are provided with working fluid passage devices as illustrated for example in WO 2004/045837, in the name of the same Applicant.

(26) The mounting/dismounting unit 5 is adapted for housing a vulcanized tyre and the respective toroidal support to perform the separation operation of the vulcanized tyre. In the present context, by the term separation operation it is meant to indicate at least all of the dismounting operations of the toroidal support, and the removal of the tyre from the aforementioned dismounted toroidal support.

(27) In accordance with an embodiment of the present invention, the first transfer device R1 is adapted for: transferring the green tyre and the respective toroidal support from the building line 2 of the production plant 1 to the first holding unit 7; transferring the toroidal support, separated from the respective tyre, from the first holding unit 7 to the cooling unit 6 of the building line 2; and transferring the toroidal support, previously separated from the respective tyre, from the cooling unit 6 of the building line 2 to a working station 10 of the building line 2.

(28) In accordance with the two embodiments shown in FIGS. 2 and 3, the production plant 1 also comprises a second holding unit 8 adapted for holding the green tyre and the relevant toroidal support coming out from the building line 2 and for holding the toroidal support, separated from the relevant tyre, coming out from the vulcanization line 3.

(29) In this case, the tyre going into the vulcanization line 3 does not come directly from a station 10 of the building line, but transits through said second holding unit 8 and therefore, in this case, the first transfer device R1 is adapted for: transferring the green tyre and the relevant toroidal support from said second holding unit 8 to the first holding unit 7; transferring the toroidal support, separated from the relevant tyre, from the first holding unit 7 to the cooling unit 6 of the building line 2; and transferring the toroidal support, separated from the respective tyre, from the cooling unit 6 of the building line 2 to the second holding unit 8.

(30) Independently from whether said second holding unit 8 is present, the second transfer device R2 is preferably adapted for: transferring the green tyre and the relevant toroidal support from the first holding unit 7 to a vulcanization unit 4 of the vulcanization line 3 of the production plant 1; transferring the moulded and vulcanized tyre and the relevant toroidal support from the vulcanization unit 4 to the mounting/dismounting unit 5 of the vulcanization line 3 of the production plant 1; and transferring the toroidal support, separated from the relevant tyre, from the mounting/dismounting unit 5 of the vulcanization line 3 to the first holding unit 7.

(31) As illustrated above, said first and second transfer devices R1 and R2 can advantageously be movable on at least one rail 9. In the embodiment illustrated in FIGS. 2 and 3, at least one pair of rails 9 constitutes as track on which the aforementioned transfer devices R1 and R2 are capable of moving (in the case illustrated, by translating).

(32) Advantageously, said rails 9 preferably extend between at least two units from the vulcanization unit 4, the mounting/dismounting unit 5, the cooling unit 6 and the second holding unit 8 and/or between a working station 10 of the building line 2 and at least one unit from the vulcanization unit 4, the mounting/dismounting unit 5, the cooling unit 6 and the second holding unit 8.

(33) In the case in which the production plant 1 is provided with a second holding unit 8, said rails 9 also extend between the cooling unit 6 and said second holding unit 8.

(34) Advantageously, the first holding unit 7 comprises at least two seats for housing the toroidal supports respectively associated with and/or separated from a green or moulded and vulcanized tyre.

(35) According to the embodiments shown in FIGS. 2-5, said first holding unit 7 comprises four seats for housing the toroidal supports.

(36) In such embodiments, the first holding unit 7 is arranged on the rail on which the first transfer device R1 and the second transfer device R2 run.

(37) According to a variant of the present invention, the first holding unit 7 is movable so as to assist the transfer of the first transfer device R1 and of the second transfer device R2 simplifying their manoeuvres and shortening the distances that they have to accomplish.

(38) In this ease, the first holding unit 7 is advantageously movable along said rails 9.

(39) In accordance with an embodiment, the production plant 1 comprises driving devices to move the first transfer device R1 and the second transfer device R2 along said rails 9. Said driving devices can be associated with the rails 9 or else with the first transfer device R1 and with the second transfer device R2.

(40) Where the productions requirements are such, it is possible to provide the vulcanization line 3 with two mounting/dismounting units 5 and/or the building line 2 with four cooling units 6.

(41) With reference to the production plant 1 illustrated in FIGS. 1-5, a preferred embodiment of a production process according to the invention will now be described.

(42) In accordance with a first step a), a green tyre is built on a respective toroidal support by assembling each structural component of the tyre according to a predetermined sequence at the aforementioned working stations 10 of the building line 2 of the production plant 1.

(43) This building step of each tyre is carried out for example according to methods illustrated in document WO 01/32409, to the same Applicant.

(44) When the building step is complete, the process for producing tyres according to the present invention provides carrying out a step b) of transferring the green tyre and the relevant toroidal support from the building line 2 of the production plant 1 to the first holding unit 7. Such a step b) is carried out through the first transfer device R1.

(45) The next step c) provides transferring the green tyre and the relevant toroidal support from the first holding unit 7 to the vulcanization line 3 through the second transfer device R2, different to the first transfer device R1.

(46) Thereafter the green tyre is moulded and vulcanized in the vulcanization line 3 of the production plant 1 so as to define the structure of the tyre according to the desired geometry and tread pattern.

(47) Once vulcanized and moulded, the tyre is separated from the relevant toroidal support in a step e) that comprises the dismounting of the toroidal support and the removal of the moulded and vulcanized tyre from said toroidal support. Preferably said step e) also comprises the subsequent remounting of the toroidal support, which is thus ready for another production cycle.

(48) At this point the toroidal support, separated from the relevant tyre, is subjected to step f) of transferral from the vulcanization line 3 to the first holding unit 7 through the second transfer device R2.

(49) Thereafter, the first transfer device R1 carries out step g) of transferring the toroidal support, from the first holding unit 7 to the building line 2 of the production plant 1.

(50) Preferably, step c) of transferring the green tyre and the relevant toroidal support from the first holding unit 7 to the vulcanization line 3 of the production plant 1 comprises step c1) of transferring the green tyre and the relevant toroidal support from the first holding unit 7 to a vulcanization unit 4 of the vulcanization line 3 through the second transfer device R2.

(51) Advantageously, the process according to the present invention, comprises the further step f1) of transferring the tyre, after it has been moulded and vulcanized, and the relevant toroidal support from the vulcanization unit 4 to the mounting dismounting unit 5 of the vulcanization line 3 through said second transfer device R2.

(52) In this case, said step f) of transferring the toroidal support, separated from the relevant tyre in the mounting/dismounting station 5, from the vulcanization line 3 to the first holding unit 7 comprises step f2) of transferring the toroidal support, after it has been separated from the relevant tyre, from the mounting/dismounting unit 5 of the vulcanization line 3 to the first holding unit 7 through said second transfer device R2.

(53) Preferably, step g) of transferring the toroidal support separated from the relevant tyre from the first holding unit 7 to the building line 2 comprises step g1) of transferring the toroidal support from the first holding unit 7 to the cooling unit 6 through the first transfer device R1.

(54) Said step g) also comprises a step g2) of transferring the toroidal support from said cooling unit 6 to a working station 10 of the building line 2 through the first transfer device R1.

(55) According to an alternative embodiment of the process for producing tyres, step f1) of transferring the vulcanized and moulded tyre and the relevant toroidal support from the vulcanization unit 4 to the mounting/dismounting unit 5 comprises the substeps of:

(56) f1) transferring the vulcanized and moulded tyre and the relevant toroidal support from the vulcanization unit 4 to the first holding unit 7; and

(57) f1) transferring the vulcanized and moulded tyre and the relevant toroidal support from the first holding unit 7 to the mounting/dismounting unit 5.

(58) In other words, according to such an alternative embodiment, the toroidal support transits by the first holding unit 7 even after the vulcanization process, before the toroidal support has been dismounted and, after the removal of the vulcanized tyre, mounted again.

(59) Preferably, step b) of transferring the green tyre and the relevant toroidal support from the building line 2 to the first holding unit 7 comprises the substeps of:

(60) b1) transferring the green tyre and the relevant toroidal support from the building line 2 to a second holding unit 8; and

(61) b2) transferring the green tyre and the relevant toroidal support from said second holding unit 8 to the first holding unit 7.

(62) In a similar manner, step g) of transferring the toroidal support, separated from the relevant tyre, from the first holding unit 7 to the building line 2 comprises the substeps of:

(63) g) transferring the toroidal support from the cooling unit 6 to the second holding unit 8; and

(64) g) transferring the toroidal support from said second holding unit 8 to the building line 2.

(65) Preferably step g) comprises the step of transferring the toroidal support from said second holding unit 8 to a working station 10 of the building line 2.

(66) According to an embodiment, the process for producing tyres for vehicle wheels comprises, before step d) of moulding and vulcanizing the tyre in the vulcanization unit 4, a pre-beating step of a mould of the corresponding vulcanization unit 4.

(67) FIG. 4 schematically shows the transferrals carried out by the first transfer device R1, in an embodiment of the present invention. Such transferrals are indicated by the arrows F1, F5 and F6.

(68) Similarly, FIG. 5 schematically shows the transferrals carried out by the second transfer device R2, in the same embodiment. These transferrals are indicated by the arrows F2, F3 and F4.

(69) The steps of the production process according to the present invention have up to now been described in sequence from the building of the green tyre up to the vulcanized tyre leaving the production plant. However, the steps of the process occur simultaneously and the units such as the vulcanization unit 4, the mounting/dismounting unit 5, the cooling unit 6 and the second holding unit 8, operate simultaneously, each on at least one tyre to carry out the step of the production process on it for which it is intended.

(70) In order to better understand the invention, with reference to FIGS. 4 and 5, it is possible to schematize the production process according to a possible embodiment of the present invention, in normal operating conditions, i.e. when the vulcanization unit 4 is full, as follows.

(71) The second transfer device R2 in sequence carries out the steps of:

(72) F3) transferring the moulded tyre and vulcanized and the relevant toroidal support from the vulcanization unit 4 to the mounting/dismounting unit 5;

(73) F2) transferring the green tyre and the relevant toroidal support from the first holding unit 7 to a vulcanization unit 4;

(74) F4) transferring the toroidal support, separated from the relevant tyre, from the mounting/dismounting unit 5 to the first holding unit 7.

(75) At the same time, the first transfer device R1 in sequence carries out the steps of:

(76) F1) transferring the green tyre and the relevant toroidal support from a station 10 of the building line 2 to the first holding unit 7;

(77) F6) transferring the toroidal support, separated from the relevant tyre, from the cooling unit 6 to a working station 10 of the building line 2;

(78) F5) transferring the toroidal support, separated from the relevant tyre, from the first holding unit 7 to the cooling unit 6.

(79) Preferably, F1) and F2) are carried out simultaneously, just as F6) is carried out simultaneously to F4) and F5) is carried out simultaneously to F4.