Tire manufacturing method and apparatus

Abstract

A tyre manufacturing method and apparatus (1) wherein: a bare carcass (5) without any tread is provided; a winding system (7) winding a raw rubber liner (8) and a pre-cured tread strip (9) around the carcass (5); and a curing system (10) curing the raw rubber liner (8) inserted in the tire (2) between the carcass (5) and the tread strip (9). The pad (8) is at least partially electrically conductive, and the pad (8) is heated during the curing process by circulating an electrical current through the pad (8). Prior to the curing process, a first power supply body (22) is placed on a first side of the liner and a second power supply body (23) is placed on a second side of the liner opposite the first side. During the curing process, a potential difference is applied between the power bodies to circulate the current through the pad (8).

Description

[0001] Specification Technical Field

[0002] The present invention relates to a method and an apparatus for manufacturing tires.

[0003] The present invention finds advantageous application in the field of retreading "truck" tires, and the following discussion will make explicit reference thereto without loss of generality. Prior Art

[0004] Traditionally, after the first use, "truck" tires are retreaded, i.e., new treads are provided to them to replace the old worn-out treads that have been previously removed. Retreading of "truck" tires provides for mechanically removing the old worn-out treads from the used tires to expose the carcass, and subsequently applying a new tread to the carcass. Applying the new tread to the carcass provides for winding a tread strip around the carcass; the carcass is then subjected to a curing process to determine the optimal adhesion of the tread to the carcass. In the hot retreading process, the tread strip is raw and has no pattern, which is achieved in a curing press equipped with a mold having the desired pattern during the curing step. In the hot retreading process, curing is carried out at a high temperature (about 150 °C to 160 °C) and a high pressure (about 1.4 MPa - 1.6 MPa, i.e., 14 bar - 16 bar), which high temperature and high pressure are required to make the rubber fluid enough to flow into the mold to form the pattern during curing; however, the thermal and mechanical stresses to which the carcass is subjected due to such high temperature and high pressure may cause damage to the carcass.

[0005] In the cold retreading process, the tread strip (referred to as "PCT - pre-cured tread - strip") is pre-cured and already has a pattern, and an intermediate strip or liner having a bonding function is interposed between the carcass and the pre-cured tread strip. In the cold retreading process, curing only means curing the liner in order to determine the optimal adhesion of the tread strip to the carcass by means of the bonding action of the liner (i.e., the pattern is not printed during curing); thus, in the cold retreading process, curing is carried out at a lower temperature (about 100 °C - 125 °C) and a lower pressure (about 0.4 MPa - 0.6 MPa, i.e., 4 bar - 6 bar), and thus the carcass is subjected to lower thermal and mechanical stresses.

[0006] Generally speaking, the hot retreading process provides an average curing period of about 1 hour for each "truck" tire, while the cold retreading process provides an average curing period of about 4 hours for each "truck" tire.

[0007] During the cold retreading process and in order to ensure (by interposing a gasket made of raw rubber strips) sufficient adhesion of the tread strip to the carcass, a radial thrust that presses the tread strip against the carcass must be applied during curing. In known manufacturing equipment, this radial thrust is obtained by inserting the tire into an autoclave in which an overpressure relative to atmospheric pressure (about 0.6 MPa, i.e., 6 bar) is achieved; and by inserting the tire into a flexible envelope in which a vacuum is initially created and then the flexible envelope is inflated with air to a pressure of about 0.45 MPa (i.e., 4.5 bar); the difference in pressure maintained during the curing cycle results in the generation of a pneumatic thrust that presses the tread strip against the carcass.

[0008] The use of an autoclave and an envelope makes it possible to apply a uniform thrust to the entire tread strip at both the peaks and valleys of the pattern and thus makes it possible to ensure optimal tread adhesion to the carcass.

[0009] Patent applications WO2020188502A1 and WO2020188503A1 disclose a method for cold retreading of tires, in which the gasket is manufactured using a composite containing a conductive material, and the curing process includes: connecting the gasket to a heat source or a power source; in this way, during the curing process, only the gasket (rather than the entire tire) is heated to the curing temperature, and thus energy can be saved and the thermal stress on the entire tire can be reduced.

[0010] Patent application WO2013029974A1 discloses a method and an apparatus for retreading pneumatic vehicle tires, in which a vulcanized tread is bonded to a prepared tire carcass through a vulcanized bonding rubber layer; a conductive layer made of a rubber composition is located between the tread and the tire carcass and contains at least one conductive filler in order to be heated by means of an electric current.

[0011] Patent application WO2013029974A1 discloses a method for regenerating a tire by arranging a vulcanized tread rubber member, a raw and conductive gasket rubber member, and a tire carcass one on top of the other and feeding an electric current to the conductive gasket rubber member to heat it. Detailed Description

[0012] The object of the present invention is to provide a tire manufacturing method and a tire manufacturing apparatus that have an easy and economical implementation and at the same time allow very uniform heating of the gasket to be applied and very uniform thrust to be applied to the entire tread strip.

[0013] According to the present invention, there is provided a tire manufacturing method and a tire manufacturing apparatus as described in the appended claims. Description of the Drawings

[0014] The present invention will now be described with reference to the accompanying drawings, which show non - limiting exemplary embodiments, in which:

[0015] ● Figure 1 is a schematic view of a cold tire manufacturing apparatus according to the present invention and provided with a curing system;

[0016] ● Figure 2 is a perspective view of the curing system;

[0017] ● Figure 3 is a perspective view of a part of the curing system removed for clarity;

[0018] ● Figure 4 is a schematic view of the curing chamber of the curing system;

[0019] ● Figure 5 and Figure 6 is a perspective view of a part of the curing chamber with components removed for clarity;

[0020] ● Figure 7 、 Figure 8 and Figure 9 are different exploded views of a part with components of Figure 5 and Figure 6 removed for clarity;

[0021] ● Figure 10 is Figure 9 a magnified view of the details of; and

[0022] ● Figure 11 and Figure 12 are a perspective view and a schematic view of the electrical contacts of the curing system.

[0023] Preferred Embodiment of the Present Invention

[0024] In Figure 1 the manufacturing apparatus for producing the tire 2 is indicated by the numeral 1; specifically, the manufacturing apparatus is configured to retread used tires 2 (but may also be configured to produce new tires).

[0025] The manufacturing apparatus 1 includes a removal system 3, in which the old worn tread (not shown) is mechanically removed from the tire 2, thereby exposing the equatorial surface 4 of the carcass 5 of the tire 2. In other words, the removal system 3 produces a bare carcass 5 presenting the equatorial surface 4 without any tread.

[0026] Furthermore, the manufacturing apparatus 1 includes a scraping system 6, in which the equatorial surface 4 of the carcass 5 is subjected to scraping to remove any local damage; the scraping operation results in the formation of pits having random and variable sizes and positions on the equatorial surface 4 of the carcass 5, and these pits are subsequently filled with raw rubber.

[0027] Manufacturing device 1 includes a winding system 7 to which the carcass 5 is transferred at the end of filling; within the winding system 7, intermediate rubber strips or liners 8 of raw rubber and pre-cured tread strips (PCT) 9 are wound around the carcass 5 (one after another). It is important to observe that the pre-cured tread strip 9 has been cured in a special mold before being wound around the carcass 5 and it is provided with a tread pattern.

[0028] Manufacturing device 1 includes a curing system 10 in which the retreaded tire 2 (i.e., provided with the pre-cured tread strip 9) undergoes a curing process for curing the liner 8 interposed between the carcass 5 and the pre-cured tread strip 9, thus resulting in an optimal adhesion of the pre-cured tread strip 9 to the carcass 5 by means of the bonding action of the liner 8. It is important to note that during the curing process, only the curing of the tread strip 8 is carried out, and no pattern of any kind is printed on the pre-cured tread strip 9 which already has a tread pattern.

[0029] The liner 8 is at least partially conductive, and during the curing process in the curing system 10, the liner 8 is heated by an electric current passing through the liner 8.

[0030] According to a possible embodiment, the liner 8 is manufactured as disclosed in patent application WO2020188503A1 and is thus made of a composite containing at least one conductive material selected from graphite, graphene, and carbon black having a surface area greater than or equal to 300 m 2 / gr in an amount of 1 phr to 30 phr.

[0031] As Figure 4 shown, the curing system 10 includes a sealed curing chamber 11 into which the tire 2 is inserted during the curing process, and the curing chamber is pressurized above ambient pressure (the overpressure is approximately 0.6 MPa, i.e., 6 bar) so as to apply a thrust force in a known manner on the pre-cured strip 9, which thrust force (by interposing the liner 8) causes the pre-cured strip 9 to be pushed against the carcass 5; specifically, as is known, when the tire 2 is in the curing chamber 11, the tire 2 is also inflated at the same overpressure as the curing chamber 11.

[0032] The curing chamber 11 is defined by two opposite base walls 12 having a circular shape and a side wall 13 having a cylindrical shape and connecting the two base walls 12 to each other. The side wall 13 is axially (i.e., along the Figure 2 and Figure 3 shown) moved towards and away from the two base walls 12 by a displacement device 15 (shown in Figure 2 ), to close (as Figure 4 shown) and open (as Figure 2 and Figure 3a curing chamber 11 as shown). In other words, the shifting device 15 causes the side wall 13 to move axially between an open position (shown in Figure 2 and Figure 3 ) and a closed position (shown in Figure 4 ). In the open position, the side wall 13 moves away from the base wall 12 and thus the curing chamber 11 opens radially to unload the cured tire 2 and load a new tire 2 to be cured. In the closed position, the side wall 13 is joined to the base wall 12 to close (seal) the curing chamber 11 to carry out the curing process.

[0033] According to a preferred embodiment, only the side wall 13 can move axially to open and close the curing chamber 11, while the two base walls 12 cannot move axially to open and close the curing chamber 11.

[0034] According to a preferred embodiment shown in the drawings, when the curing chamber 11 is closed (as Figure 4 shown), the two base walls 12 are completely disposed within the side wall 13. In other words, the outer diameter of the two base walls 12 is substantially equal to (in fact, slightly less than) the inner diameter of the side wall 13.

[0035] Each base wall 12 includes an annular sealing gasket 16 which is disposed on the edge of the base wall 12 such that it is interposed between the base wall 12 and the side wall 13 when the curing chamber 11 is closed (as Figure 4 shown) to ensure the enclosed pressurized curing chamber 11. The purpose of the annular sealing gasket 16 is to ensure the sealing of the curing chamber 11 when the curing chamber 11 is pressurized. According to a preferred embodiment shown in the drawings, each base wall 12 includes an annular groove which is disposed on the edge of the base wall 12 and houses the annular sealing gasket 16.

[0036] According to a preferred embodiment, each annular sealing gasket 16 is inflatable, i.e., its size can be increased by being inflated and decreased by being deflated. The curing system 10 includes a pneumatic device 17 (schematically shown in Figure 4 ) which is configured to inflate the annular sealing gasket 16 after the curing chamber 11 has been closed (to increase the pneumatic seal before pressurizing the curing chamber 11) and deflate the annular sealing gasket 16 before the curing processing chamber 11 is opened (to reduce the friction against the side wall 13 and thus allow the displacement of the side wall 13).

[0037] As Figure 3As better shown, the shifting device 15 includes: two parallel tracks 18, which are arranged axially (i.e., parallel to the central symmetry axis 14) above the side wall 13; and four sliders 19, each of the four sliders sliding along a corresponding track 18. In addition, the shifting device 15 includes two rods 20, each of the two rods having a U-shaped configuration, the two rods being connected to the side wall 13 at two different points and connected to two corresponding sliders 19; in other words, in each rod, the two vertical "legs" of the U-shaped configuration terminate at the side wall 13, while the horizontal central portion of the U-shaped configuration is connected to the two sliders at two opposite ends. According to different embodiments not shown, the number and conformation of the tracks 18, sliders 19, and rods 20 may be different.

[0038] According to a preferred embodiment, the tire 2 is supported within the curing chamber 11 by two clamps 21 (one of which is shown in Figure 6 ), the two clamps being arranged within the curing chamber 11 and being able to move relative to each other to move towards and away from each other to respectively clamp and release the tire 2. Specifically, the clamps 21 press against the annular bead regions of the tire 2. According to a preferred embodiment, the clamps 21 are fixed to the inner side of the base wall 12 (i.e., each clamp is supported by a corresponding base wall 12); in this embodiment, one base wall 12 (i.e., one clamp 21) is directly fixed to the frame of the curing chamber 11 and never makes any axial movement relative to the frame, while the other base wall 12 (i.e., the other clamp 21) is able to move axially to move the corresponding clamp 21 towards and away from the other clamp 21. The clamps 21 together with the base walls 12 or only the clamps 21 may have a rotational movement to correctly position the tire 2 on the bead; in other words, the clamps 21 may have a rotational movement to correctly position the tire 2 by allowing the rotation of the tire 2 (in this way, the tire 2 can find the correct angular position).

[0039] It is important to note that one base wall 12 is able to move axially (e.g., using a pneumatic cylinder or a hydraulic cylinder) not to open and close the curing chamber 11, but only to move the corresponding clamp 21 towards and away from the other clamp 21.

[0040] As Figure 7 、 Figure 8 and Figure 9 shown, the curing system 10 includes two power bodies 22 and 23, the two power bodies being arranged on two sides of the tire 2 within the curing chamber 11; in other words, each power body 22 or 23 is arranged within the curing chamber 11 and on the side of a corresponding base wall 12. Before the curing process, the power body 22 is placed on the first side of the gasket 8, and the power body 23 is placed on the second side of the gasket 8 opposite the first side. The curing system 10 includes ( Figure 4The electrical device 24 (schematically shown in [the figure]) is configured to apply a potential difference between two power bodies 22 and 23 during the curing process to cause current to circulate through the gasket 8 (which is interposed between the two power bodies 22 and 23 and thus forms a "conductive bridge" between the two power bodies 22 and 23). As described above, the gasket 8 is at least partially conductive and thus allows current to circulate through itself when subjected to the potential difference applied by the two power bodies 22 and 23 (thereby generating heat according to the Joule effect).

[0041] According to a preferred embodiment, the power bodies 22 and 23 are also interchangeable for different sizes of tires 2; that is, the power bodies 22 and 23 can be disassembled and replaced when the size of the tire 2 is changed.

[0042] Specifically, the two power bodies 22 and 23 are pushed towards each other with a predetermined thrust to clamp the gasket 8 between the two power bodies 22 and 23, thereby mainly forming a seal-off from the pressurized area (between the sidewall of the carcass 5 and the precured tread strip 9), and also reducing the electrical contact resistance between the power bodies 22 and 23 and the gasket 8. In other words, the pressurized area must be kept separated from the precured tread strip 9, and for this purpose, the power bodies 22 and 23 are pushed towards each other with a predetermined thrust to form a seal that isolates the pressurized area. In addition, to reduce the electrical contact resistance between the power bodies 22 and 23 and the gasket 8, the two power bodies 22 and 23 must be well adhered to the gasket 8, and thus the two power bodies must be pushed towards each other to clamp the gasket 8 between the two power bodies.

[0043] According to a preferred embodiment, each power body 22 or 23 has an annular rubber layer (referred to as a "flexible sidewall matrix"), which functions as an electrical insulator and also functions as a gasket to ensure the necessary pneumatic seal (like an envelope). In other words, the annular rubber layer of each power body 22 or 23 is designed as a gasket to ensure the necessary pneumatic seal and also provides good electrical insulation (as made of rubber).

[0044] According to a preferred embodiment shown in the drawings, the first power body 22 has a flat annular surface 25, which is everywhere made of a conductive material and forms contact with the first side of the gasket 8 (i.e., is configured to contact the gasket 8). In other words, the entire flat annular surface 25 has the same potential everywhere and constitutes a single "large" electrode. Preferably, the power body 22 is connected to the negative electrode of the electrical device 24 that applies the potential difference, i.e., the ground electrode (as Figure 4 shown).

[0045] According Figure 8 and Figure 9In a preferred embodiment shown, the power supply body 23 includes a plurality of pin-shaped contact members 26. Each of the plurality of pin-shaped contact members axially (vertically) protrudes from the power supply body 23 and forms contact with the second side of the gasket 8 (i.e., the pin-shaped contact members 26 are configured to contact the gasket 8). According to a preferred embodiment, the pin-shaped contact members 26 are arranged uniformly along the circumference. Preferably, each pin-shaped contact member 26 is connected to the positive electrode of an electrical device 24 to which a potential difference is applied.

[0046] As Figure 9 and Figure 10 shown, each pin-shaped contact member 26 is connected to the electrical device 24 by means of a dedicated wire 27 (i.e., each wire 27 is connected to one and only one pin-shaped contact member 26, and vice versa). Preferably, the wire 27 is plugged into a connector 28 that can be connected to the electrical device 24. In this way, the electrical device 24 can apply a potential different from that of all other pin-shaped contact members 26 to each pin-shaped contact member 26 (i.e., each pin-shaped contact member 26 can be individually controlled by the electrical device 24). It is important to note that, for the sake of clarity, only a very limited number of wires 27 are shown in Figure 9 and Figure 10 , but, in fact, the curing system 10 includes a dedicated wire 27 for each pin-shaped contact member 26.

[0047] As Figure 11 and Figure 12 shown, each pin-shaped contact member 26 includes a (more or less sharp) tip 29 that forms contact with the second side of the gasket 8 and is spring-loaded. In other words, in each pin-shaped contact member 26, the tip 29 is mounted to be able to slide axially within the housing 30 and is pushed towards the outside of the housing by a spring 31. In this way, the thrust applied by each pin-shaped contact member 26 against the gasket 8 is substantially constant (which depends only on the elastic force generated by the spring 31, which is constant to a first approximation) and thus this thrust is always the same for all pin-shaped contact members 26.

[0048] According to Figure 9 and Figure 10 a preferred embodiment shown, the pin-shaped contact members 26 are supported by a support ring 32 made of an electrically insulating material; in this way, each pin-shaped contact member 26 is electrically insulated from other pin-shaped contact members 26.

[0049] According to a preferred embodiment, the electrical device 24 is configured to: control the intensity of the current flowing through each pin-shaped contact 26 independently of the intensity of the current flowing through the other pin-shaped contacts 26; control the intensity of the current flowing through each pin-shaped contact 26 by controlling the voltage applied to each pin-shaped contact 26, and thus also control the voltage applied to each pin-shaped contact 26, independently of the voltage applied to the other pin-shaped contacts 26. Preferably, the electrical device 24 is configured to calculate (determine) the resistance experienced by each pin-shaped contact 26 (i.e., the resistance existing between the pin-shaped contact 26 representing the positive electrode and the power body 22 representing the negative electrode), and calculate (determine) the local temperature of the pad 8 corresponding to that pin-shaped contact 26 based on the resistance experienced by each pin-shaped contact 26 (specifically, determine the resistivity based on the resistance, and then determine the temperature based on the resistivity, since the law correlating resistivity and temperature is known). In addition, the electrical device 24 is configured to: use the local temperature of the pad 8 corresponding to each pin-shaped contact 26 as a feedback variable to feedback control the intensity of the current flowing through that pin-shaped contact 26.

[0050] According to a preferred embodiment, during the curing process, electrical parameters of each pin-shaped contact 26, specifically current and voltage, are monitored and recorded. In this way, after the curing process, it can be verified that the curing process has been carried out in the correct manner.

[0051] The above-mentioned tire manufacturing device 1 is configured to retread used tires, and thus, the bare carcass 5 is obtained by removing the old worn tread from the used tire; according to different embodiments, the tire manufacturing device 1 is configured to produce new tires, and thus the bare carcass 5 is made by winding flat rubber strips.

[0052] The above-mentioned tire manufacturing device 1 has many advantages.

[0053] First of all, the above-mentioned tire manufacturing device 1 allows a very uniform heating of the pad 8; in other words, heat is directly generated inside the pad 8 by the Joule effect (i.e., due to the current circulating through the pad 8 acting as a resistor), and is equal along the entire pad 8.

[0054] Due to the fact that heat is directly generated and only generated where it is needed (i.e., in the pad which is the only component that has to be cured and thus has to be heated), the above-mentioned tire manufacturing device 1 allows minimizing energy consumption.

[0055] The above-mentioned tire manufacturing equipment 1 exhibits a high productivity (measured as the number of tires 2 retreaded per unit time) to the extent that the curing process is extremely short: approximately 25 minutes - 35 minutes is sufficient to completely cure the liner 8 (using a very small amount of energy in total); this result is obtained because heat is directly generated within the liner 8, whereas in a conventional curing autoclave, the heat within the autoclave must first heat the pre-cured tread strip 9 (arranged more externally), and then the heat is transferred from the pre-cured tread strip 9 to the liner 8.

[0056] In addition, the above-mentioned tire manufacturing equipment 1 allows for a very uniform thrust to be applied to the entire pre-cured tread strip 9 by using a pneumatic system to apply the thrust.

[0057] The above-mentioned tire manufacturing equipment 1 allows the curing chamber 11 to be opened and closed in a quick and simple manner, and when the curing chamber 11 is open, the unloading of the cured tire 2 and the loading of a new tire 2 to be cured are very easy because the access to the curing chamber 11 is wide by removing the side wall 13. Finally, the above-mentioned tire manufacturing equipment 1 is compact and relatively inexpensive.

[0058] List of Reference Numerals of the Drawings

[0059] 1 Retreading equipment

[0060] 2 Tire

[0061] 3 Removal system

[0062] 4 Equatorial surface

[0063] 5 Carcass

[0064] 6 Scraping system

[0065] 7 Winding system

[0066] 8 Liner

[0067] 9 Pre-cured tread strip

[0068] 10 Curing system

[0069] 11 Curing chamber

[0070] 12 Base wall

[0071] 13 Side wall

[0072] 14 Central axis

[0073] 15 Shifting equipment

[0074] 16 Annular sealing gasket

[0075] 17 Pneumatic equipment

[0076] 18 tracks

[0077] 19 sliders

[0078] 20 rods

[0079] 21 clamps

[0080] 22 power bodies

[0081] 23 power bodies

[0082] 24 electrical devices

[0083] 25 surfaces

[0084] 26 pin-shaped contacts

[0085] 27 electric wires

[0086] 28 connectors

[0087] 29 tips

[0088] 30 housings

[0089] 31 springs

[0090] 32 support rings

Claims

1. A tire manufacturing method for manufacturing a tire (2), and the tire manufacturing method comprises the following steps: providing a bare carcass (5) presenting an equatorial surface (4) without any tread; in a winding system (7), winding at least a partially conductive uncured rubber liner (8) and a pre-cured tread strip (9) around the equatorial surface (4) of the carcass (5); curing the uncured rubber liner (8) inserted into the tire (2) between the carcass (5) and the tread strip (9) in a curing system (10); heating the liner (8) by circulating an electric current through the liner (8) during the curing process; placing a first power supply body (22) on a first side of the liner (8) and placing a second power supply body (23) on a second side of the liner (8) opposite to the first side before the curing process; and applying a potential difference between the first power supply body (22) and the second power supply body (23) during the curing process to cause the electric current to circulate through the liner (8); the manufacturing method is characterized in that the second power supply body (23) comprises a plurality of pin-shaped contact members (26), and each of the plurality of pin-shaped contact members axially projects from the second power supply body (23).

2. The tire manufacturing method according to claim 1, wherein the first power supply body (22) has an annular surface (25) which is everywhere made of a conductive material and forms contact with the first side of the liner (8).

3. The tire manufacturing method according to claim 2, wherein the first power supply body (22) is connected to the negative electrode, i.e., the ground electrode, of an electrical device (24) for applying the potential difference.

4. The tire manufacturing method according to claim 1, 2 or 3, wherein the pin-shaped contact members (26) are arranged along a circumference.

5. The tire manufacturing method according to any one of claims 1 to 4, wherein each pin-shaped contact member (26) is connected to the positive electrode of an electrical device (24) for applying the potential difference.

6. The tire manufacturing method according to any one of claims 1 to 5, wherein each pin-shaped contact member (26) comprises a tip (29) which forms contact with the second side of the liner (8) and is spring (31)-loaded.

7. The tire manufacturing method according to claim 6, wherein in each pin-shaped contact member (26), the tip (29) is mounted to be axially slidable and is pushed outward by a spring (31).

8. The tire manufacturing method according to any one of claims 1 to 7, wherein the pin-shaped contact members (26) are supported by a support ring made of an electrically insulating material.

9. The tire manufacturing method according to any one of claims 1 to 8, and the tire manufacturing method comprises the following steps: controlling the intensity of the electric current flowing through each pin-shaped contact member (26), the control being independent of the intensity of the electric current flowing through other pin-shaped contact members (26).

10. The tire manufacturing method according to any one of claims 1 to 9, and the tire manufacturing method further comprises the following steps: Calculate the resistance experienced by each pin-shaped contact (26); and Calculate the local temperature of the gasket (8) corresponding to the pin-shaped contact (26) based on the resistance experienced by each pin-shaped contact (26).

11. The tire manufacturing method according to claim 10, and the tire manufacturing method further comprises the following step: using the local temperature of the gasket corresponding to each pin-shaped contact (26) as a feedback variable to feedback control the intensity of the current flowing through the pin-shaped contact (26).

12. The tire manufacturing method according to any one of claims 1 to 11, and the tire manufacturing method further comprises the following step: monitoring and recording electrical parameters of each pin-shaped contact (26), specifically current and voltage, during the curing process.

13. The tire manufacturing method according to any one of claims 1 to 12, wherein: The curing chamber (11) is defined by two opposite base walls (12) having a circular shape and side walls (13) having a cylindrical shape and connecting the two base walls (12) to each other; and The side walls (13) are axially moved towards and away from the two base walls (12) respectively by means of a shifting device (15) to close and open the curing chamber (11).

14. The tire manufacturing method according to claim 13, wherein each power supply body (22, 23) is arranged inside the curing chamber (11) and on the side of the corresponding base wall (12).

15. The tire manufacturing method according to any one of claims 1 to 14, wherein two power supply bodies (22, 23) are pushed towards each other with a predetermined thrust to clamp the gasket (8) between the two power supply bodies (22, 23), and thus ensure an airtight seal between the carcass (5) and the pre-cured tread strip (9).

16. The tire manufacturing method according to any one of claims 1 to 15, wherein each power supply body (22, 23) has an annular rubber layer, which functions as an electrical insulator and also functions as a gasket to ensure the necessary pneumatic seal.

17. A manufacturing device (1) for producing a tire (2), and the manufacturing device comprises: A working system configured to provide a bare carcass (5) presenting an equatorial surface (4) without any tread; A winding system (7) configured to wind at least a partially conductive uncured rubber gasket (8) and a pre-cured tread strip (9) around the equatorial surface (4) of the carcass (5); and A curing system (10) configured to cure the uncured rubber gasket (8) inserted into the tire (2) between the carcass (5) and the tread strip (9); wherein the curing system (10) includes heating equipment configured to heat the gasket (8) by circulating a current through the gasket (8) during the curing process; Wherein the heating device includes: a first power supply body (22), the first power supply body being configured to be placed on a first side of the gasket (8) before the curing process; a second power supply body (23), the second power supply body being configured to be placed on a second side of the gasket (8) opposite to the first side before the curing process; and an electrical device (24), the electrical device being configured to apply a potential difference between the first power supply body (22) and the second power supply body (23) during the curing process to cause an electric current to circulate through the gasket (8); The manufacturing device (1) is characterized in that the second power supply body (23) includes a plurality of pin-shaped contact members (26), and each of the plurality of pin-shaped contact members axially projects from the second power supply body (23).

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