Equipment for vulcanizing and molding tires, and methods for preheating circumferential sectors in equipment for vulcanizing and molding tires.

Abstract

An apparatus for vulcanizing and molding tires includes an annular container (16) that engages or is configured to engage a plurality of circumferential sectors (10). The annular container (16) is movable between a raised position and a lowered position, in which the circumferential sectors (10) are circumferentially spaced apart from each other, and in the lowered position, the annular container (16) surrounds the circumferential sectors (10), and the circumferential sectors (10) move circumferentially closer to each other. A conduit (26) for circulating a heating medium is provided within the annular container (16). The conduit (26) surrounds the circumferential sectors (10) and has a wavy pattern extending wavyly toward a bottom (18) and toward a top (17).

Description

Technical Field

[0001] This invention relates to a process and apparatus for producing tires for vehicle wheels.

[0002] The production cycle of tires for vehicle wheels provides a build process in which various structural components of the tire itself can be manufactured and / or assembled on one or more drums to produce a green tire. The green tire is then transferred to a molding and vulcanizing line, where molding and vulcanizing processes are actuated. The molding and vulcanizing processes are adapted to define the tire's structure according to the desired geometry and tread design.

[0003] This invention relates to an apparatus for vulcanizing and molding tires, and a method for preheating a circumferential sector in the apparatus. The invention particularly relates to the conduit design of the apparatus for vulcanizing and molding tires, the conduit carrying a heating medium used to heat a mold containing a raw tire to be molded and vulcanized. Background Technology

[0004] Components used for vulcanizing and molding tires are known in the art.

[0005] Document US20090162460A1 provides a mold assembly comprising multiple segments arranged to form an annular ring when assembled together. Multiple sliders surround these segments for receiving and supporting them. The sliders are slidable in a radial direction. The container housing also includes an annular actuating ring. The inner radial surface of the actuating ring is angled to engage with the outer angled surface of the slider. The tread mold segments have an outer radial surface having channels for receiving tubular components or X-shaped couplings for the passage of heating steam.

[0006] Document CN204196061U describes a steam chamber guide ring for a tire segmentation mold. The steam chamber guide ring includes a guide ring body, a steam inlet, and a steam outlet. One or more steam circulation grooves are formed in the inner conical surface of the guide ring body. The steam circulation groove at the top end communicates with the steam inlet, and the steam circulation groove at the bottom end communicates with the steam outlet. A steam circulation hole is provided between two adjacent steam circulation grooves.

[0007] Document JP2015155151A discloses a container for a tire vulcanizing machine. The container includes a cavity with a steam pipe disposed within it for supplying steam to the cavity. The steam pipe includes: multiple steam inlet ports to be connected to an external pipe for introducing steam; and a steam outlet port from which the introduced steam is discharged into the cavity. The container includes a steam discharge port from which the steam introduced into the cavity is discharged into the external pipe at a position symmetrical to the steam outlet port. Multiple baffles are also installed within the cavity, causing the steam introduced into the cavity to meander through the cavity.

[0008] Additional mold assembly for molding tires is disclosed in documents CN104690856, CN204820080U and JP5036419B2, which includes a container having an annular channel for steam.

[0009] definition

[0010] Unless otherwise stated, “tire” means raw tire or molded and vulcanized tire.

[0011] The terms "radial" and "axial," as well as the expressions "radial in / outer" and "axial in / outer," are used with reference to the radial direction (i.e., with reference to the direction perpendicular to the geometric axis of rotation of the equipment or the tire within the equipment, where the two axes substantially coincide) of the equipment and the tire, and the axial direction (i.e., with reference to the direction parallel to the geometric axis of rotation of the equipment or the tire within the equipment) of the equipment and the tire. The radial plane of the tire encompasses its axis of rotation.

[0012] The terms “circumferential” and “circumferentially” are used in reference to the circumferential extension of the equipment and the tires within it.

[0013] The terms “low,” “below,” “lower,” “bottom,” and “high,” “above,” “upper,” and “top” are used to indicate the relative position of the reference element to the ground during normal use. Summary of the Invention

[0014] The applicant has observed that the aforementioned prior art mold assembly involves the following key aspects: the instantaneous heating rate of the mold assembly, the heat distribution across the entire mold assembly, the cycle time, the setup time, the heating loss, and the steam consumption.

[0015] The applicant has observed that the segments of the mold are heated by thermal conduction of steam circulating through the annular ring to the segments. When the mold is closed and the annular ring surrounds the segments, the heat of the steam flowing through the tubes formed in the annular ring moves through the walls of the annular ring by conduction and then reaches the segments that are in contact with the radially inner surface of the annular ring.

[0016] The applicant has observed that after each vulcanization and molding cycle, when the mold is opened by raising the annular ring and radially opening the segment to remove the vulcanized and molded tire and load the raw tire to be vulcanized and molded, the segment cools down and must be reheated by the annular ring once the annular ring is recoupled to the segment.

[0017] The applicant has observed that the shape and position of the tube in the prior art, which is an annular ring, cannot heat the segments in an effective and rapid manner.

[0018] In particular, the applicant has observed that the annular tubes of the prior art allow a reduced amount of heat to be transferred to the segments and this results in significant heat loss.

[0019] The applicant has also observed that the tubes of the prior art, which are annular rings, do not allow for a uniform distribution of heat to the segments and produce cold spots that can impair the efficiency and performance of the equipment and may also impair the quality of the manufactured tires.

[0020] The applicant has observed that the aforementioned defects also negatively impact setup time (the time for heating the mold after loading and shutting down and before starting the vulcanization and molding cycle) and vulcanization and molding cycle time.

[0021] The applicant has recognized the need to improve the heating efficiency of segments and the entire mold during vulcanization and molding processes in order to improve tire quality, shorten vulcanization and molding cycle time, and reduce power consumption.

[0022] The applicant has recognized the need to address the aforementioned drawbacks by designing steam pipes within an annular ring in order to maximize heat transfer from steam to the radially outer portion of the circumferential sector.

[0023] The applicant has finally discovered that the above and other objectives can be achieved by bringing the tube and heating medium as close as possible to the circumferential sector and by widening the inner surface of the tube as quickly as possible to cover most of the radially outer portion of the circumferential sector.

[0024] According to a first aspect, the present invention relates to an apparatus for vulcanizing and molding tires.

[0025] Preferably, the apparatus for vulcanizing and molding tires includes a plurality of circumferential sectors arranged around a central axis, the plurality of circumferential sectors being movable between a first position and a second position, in the first position being circumferentially spaced apart from each other and away from the central axis, and in the second position being circumferentially closer to each other and closer to the central axis.

[0026] Preferably, the apparatus for vulcanizing and molding tires includes an annular container having a top, a bottom, a radially inner surface, and a radially outer surface; the annular container engages with or is configured to engage with a circumferential sector, the annular container being movable between a raised position and a lowered position, in which the circumferential sector is in a first position, and in the lowered position, the annular container surrounds the circumferential sector and the circumferential sector is in a second position; wherein, in the lowered position, the radially inner surface of the annular container contacts the radially outer portion of the circumferential sector.

[0027] Preferably, when the annular container is in the lowered position and the circumferential sector is in the second position, the device defines a vulcanizing and molding cavity for accommodating the tire.

[0028] Preferably, a conduit for circulating the heating medium is provided in the annular container, and when the annular container is in the lowered position, the conduit surrounds the circumferential sector.

[0029] Preferably, the conduit extends toward the bottom and toward the top in a wave pattern.

[0030] According to a second aspect, the present invention relates to a method for preheating a circumferential sector in an apparatus for vulcanizing and molding tires.

[0031] Preferably, the method includes: providing an annular container, the annular container being positioned or configured to surround a plurality of circumferential sectors arranged around a central axis, the plurality of circumferential sectors defining vulcanization and molding cavities.

[0032] Preferably, the method includes: flowing a heating medium through a waveform pattern formed in an annular container, the waveform pattern extending from the top to the bottom and from the bottom to the top of the annular container.

[0033] Preferably, the radially inner surface of the annular container contacts or is configured to be in contact with the radially outer portion of the circumferential sector.

[0034] Preferably, the device is the device described in the first aspect.

[0035] The applicant believes that the present invention allows the achievement of the above objectives.

[0036] The applicant believes that, compared with the content disclosed in the cited references, the present invention achieves a more uniform temperature distribution (i.e., fewer cold spots) across the entire annular container.

[0037] The applicant also believes that the components including the annular container and circumferential sector of the present invention reach a temperature stable state more quickly than the components disclosed in the cited references.

[0038] The applicant also believes that the present invention allows for a reduction in heat loss and steam consumption and thus allows for a reduction in energy consumption relative to what is disclosed in the cited references.

[0039] The applicant also believes that the present invention allows for shorter vulcanization and molding cycle times and shorter setup times.

[0040] The present invention may have one or more of the preferred features described below.

[0041] Preferably, the heating medium is steam, and more preferably water steam.

[0042] Preferably, in the diametrical cross-section of the annular container, at least some portions of the conduit are closer to the radially inner surface of the annular container than to the radially outer surface of the annular container.

[0043] Preferably, the heating medium is directed to flow closer to the radial inner surface of the annular container than to the radial outer surface of the annular container.

[0044] Preferably, the annular container includes a discharge channel connected to a conduit.

[0045] Preferably, a condensation section is specified where steam is discharged from the waveform section or from the conduit.

[0046] Preferably, the discharge is carried out while the steam is flowing through the waveform section or conduit.

[0047] The applicant has demonstrated that the exhaust channel allows for the removal of condensate from the steam and makes the steam drier, thus improving heat transfer capacity. In fact, steam dryness directly affects the total amount of transferable energy contained within the steam, which in turn affects heating efficiency and quality. Supplying steam that is as close to dry as possible enables higher heating efficiency.

[0048] Preferably, the discharge channel is annular and surrounds the central axis.

[0049] Preferably, the discharge channel is located below the catheter.

[0050] Preferably, the annular container includes at least one discharge port for connecting the conduit to the discharge channel.

[0051] Preferably, the conduit includes a plurality of top portions and a plurality of bottom portions that follow each other in an alternating manner.

[0052] Preferably, the discharge channel is connected to at least one of the bottom portions.

[0053] Preferably, the discharge channel is connected to all bottom portions.

[0054] Preferably, the discharge hole includes a radial portion and an axial portion.

[0055] Preferably, the discharge channel is connected to the outlet opening to discharge condensate.

[0056] The applicant has demonstrated that connecting the drain channel to one or all of the bottom sections facilitates the removal of condensate that tends to drip and settle downwards.

[0057] Preferably, the annular container includes a ring connected to the bottom of the annular container, the ring having a groove defining a discharge channel.

[0058] Preferably, the ring follows the circumferential profile of the annular container.

[0059] Preferably, each of the portions of the catheter has a flat shape.

[0060] Preferably, each of the portions of the catheter has two dimensions that are much larger than the third dimension.

[0061] Preferably, the third dimension is perpendicular to the radial inner surface of the annular container.

[0062] Preferably, each of the portions is defined by a first inner surface parallel to the radial inner surface of the annular container, a second inner surface facing the first inner surface, and an edge inner surface connecting the first and second inner surfaces.

[0063] Preferably, the first inner surface and the second inner surface are parallel to each other.

[0064] Preferably, the first inner surface and the second inner surface are identical to each other.

[0065] Preferably, the first inner surface is farther from the radial inner surface of the annular container than the second inner surface.

[0066] Preferably, the ratio "A1 / g" of the area "A1" of the first inner surface to the gap "g" between the first inner surface and the second inner surface is equal to or greater than 1000 mm.

[0067] Preferably, the ratio "A1 / g" of the area "A1" of the first inner surface to the gap "g" between the first inner surface and the second inner surface is equal to or less than 2000 mm.

[0068] Preferably, the ratio "A1 / C" of the area "A1" of the first inner surface to the width "C" of the vulcanization and molding cavity is equal to or greater than 80 mm.

[0069] Preferably, the ratio "A1 / C" of the area "A1" of the first inner surface to the width "C" of the vulcanization and molding cavity is equal to or less than 100 mm.

[0070] Preferably, the ratio “A1 / d1” of the area “A1” of the first inner surface to the first distance “d1” from the first inner surface to the radial inner surface of the annular container is equal to or greater than 1000 mm.

[0071] Preferably, the ratio “A1 / d1” of the area “A1” of the first inner surface to the first distance “d1” from the first inner surface to the radial inner surface of the annular container is equal to or less than 2000 mm.

[0072] Preferably, the first distance "d1" is measured perpendicular to the first inner surface.

[0073] Preferably, the ratio “A1 / d2” of the area “A1” of the first inner surface to the minimum radial distance “d2” from the second inner surface to the radial outer surface of the annular container is equal to or greater than 100 mm.

[0074] Preferably, the ratio “A1 / d2” of the area “A1” of the first inner surface to the minimum radial distance “d2” from the second inner surface to the radial outer surface of the annular container is equal to or less than 200 mm.

[0075] Preferably, the ratio “D / d2” of the maximum inner diameter “D” of the vulcanizing and molding cavity to the minimum radial distance “d2” from the second inner surface to the radial outer surface of the annular container is equal to or greater than 10 mm.

[0076] Preferably, the ratio “D / d2” of the maximum inner diameter “D” of the vulcanizing and molding cavity to the minimum radial distance “d2” from the second inner surface to the radial outer surface of the annular container is equal to or less than 20 mm.

[0077] Preferably, the ratio "d2 / d1" of the minimum radial distance "d2" from the second inner surface to the radial outer surface of the annular container to the first distance "d1" from the first inner surface to the radial inner surface of the annular container is equal to or greater than 5.

[0078] Preferably, the ratio “d2 / d1” of the minimum radial distance “d2” from the second inner surface to the radial outer surface of the annular container to the first distance “d1” from the first inner surface to the radial inner surface of the annular container is equal to or less than 20.

[0079] Preferably, the ratio "h / C" of the height "h" of the first inner surface to the width "C" of the vulcanization and molding cavity is equal to or greater than 0.7.

[0080] Preferably, the ratio "h / C" of the height "h" of the first inner surface to the width "C" of the vulcanization and molding cavity is equal to or less than 0.9.

[0081] Preferably, the height "h" is measured in the diametrical section of the annular container and parallel to the first inner surface.

[0082] Preferably, the ratio "w / C" of the width "w" of the first inner surface to the width "C" of the vulcanization and molding cavity is equal to or greater than 0.4.

[0083] Preferably, the ratio "w / C" of the width "w" of the first inner surface to the width "C" of the vulcanization and molding cavity is equal to or less than 0.6.

[0084] Preferably, the width "w" is measured along the circumferential direction of the annular container.

[0085] Preferably, when viewed in the radial direction, each of the portions is a U-shaped segment of a catheter.

[0086] Preferably, the lower bend of the U-shaped section is one of the bottom portions of the catheter.

[0087] Preferably, each of the two upper ends of the U-shaped segment is connected to the adjacent U-shaped segment via one of the top portions.

[0088] Preferably, each top portion includes a connection hole, one end of which is connected to the upper end of one of the U-shaped segments and the other end of which is connected to the upper end of the other of the U-shaped segments.

[0089] Preferably, each of the portions of the conduit is defined by a groove formed in the radially inner surface of the annular container.

[0090] Preferably, each of the portions of the conduit is defined by a plate with a closed groove.

[0091] Preferably, the first distance "d1" is the thickness of the plate.

[0092] Preferably, the radially inner working surface of the plate defines a portion of the inner surface of the annular container.

[0093] Preferably, the radially inner working surface of the plate is flush with the rest of the inner surface of the annular container.

[0094] Preferably, each plate has a rectangular or trapezoidal profile.

[0095] Preferably, in the lowered position, the plate engages with the radially outer portion of the circumferential sector.

[0096] Preferably, the plate is made of a material with a thermal conductivity between 100 W / (m*K) and 180 W / (m*K).

[0097] Preferably, the plate is made of a material with a hardness between 40HB and 210HB.

[0098] Preferably, the plate is made of a material selected from the group consisting of brass or an alloy comprising copper, nickel and silicon or an alloy comprising copper, tin, zinc and lead.

[0099] Preferably, when the annular container is in the lowered position, each circumferential sector is coupled to a plurality of said portions.

[0100] Preferably, the catheter has an inlet and an outlet.

[0101] Preferably, the inlet and outlet are formed on the radial outer surface of the annular container.

[0102] Preferably, the entrance and exit are close to each other.

[0103] Preferably, the radial inner surface of the annular container has a truncated conical shape.

[0104] Preferably, the plate is disposed on the radial inner surface of the annular container.

[0105] Preferably, the radially outer portion of the circumferential sector is disposed on the surface of a virtual truncated cone.

[0106] Preferably, the average velocity of the heating medium in the waveform section or in the conduit is between 15 m / s and 25 m / s, and optionally 20 m / s.

[0107] Preferably, the flow rate of the heating medium through the waveform section or through the conduit is between 4m³. 3 / s and 8m 3 Between / s.

[0108] Preferably, the annular container is made of structural steel.

[0109] Preferably, the ring is made of structural steel.

[0110] Preferably, the circumferential sector is supported by an annular container.

[0111] Preferably, the annular container includes a plurality of guides positioned on a radially inner surface, and circumferential sectors are coupled to the guides for sliding along the guides.

[0112] Preferably, each guide is placed between two adjacent plates.

[0113] Preferably, as the annular container moves between the raised and lowered positions, the circumferential sector slides along the guide between the first and second positions.

[0114] Preferably, each of the circumferential sectors includes a support block and a working section.

[0115] Preferably, the working section is positioned radially inward relative to the support block.

[0116] Preferably, the support block includes a radially outer portion.

[0117] Preferably, the support block slides along the guide between a first position and a second position.

[0118] Preferably, the working section is mounted on the support block.

[0119] Preferably, the working section includes a working surface configured to engage with a tire placed in the vulcanization and molding cavity.

[0120] Preferably, the surface is configured to engage with the radially outer portion of the tire.

[0121] Preferably, each working segment is removably connected to a corresponding support block, such that the working segment can be replaced by another working segment.

[0122] Preferably, when the working section is mounted on the corresponding support block, the working section and the support block are integrated with each other and move together between the first position and the second position.

[0123] Preferably, the device further includes an axially opposed first sidewall plate and a second sidewall plate, each of the first sidewall plate and the second sidewall plate having a working surface for operating the tire bead and sidewall of a pair of tires.

[0124] Further features and advantages will become clearer from the detailed description of preferred, but not exclusive, embodiments of the apparatus for vulcanizing and molding tires according to the invention, and of the method for preheating the circumferential sector in the apparatus for vulcanizing and molding tires. Attached Figure Description

[0125] The following description will refer to the accompanying drawings, which are provided as non-limiting examples only, wherein:

[0126] - Figure 1 A vulcanizing mold belonging to an apparatus for vulcanizing and molding tires according to the present invention is shown in diametrical cross-sectional view;

[0127] - Figure 2 yes Figure 1 A 3D view of the device's components, where some parts are transparent to better display other parts;

[0128] - Figure 3 yes Figure 2 The enlarged portion of the components, in which some parts have been removed;

[0129] - Figure 4 It shows Figure 1 A 3D view of a part of the device;

[0130] - Figure 5 It shows Figure 2 The steam flow path inside the component;

[0131] - Figure 6 This is a diameter cross-sectional view of a portion of the equipment shown in the aforementioned figure;

[0132] - Figure 7 It is the cross-sectional view of the equipment shown in the aforementioned figure;

[0133] - Figure 8 These are different cross-sectional views of the equipment shown in the aforementioned diagram;

[0134] - Figure 9 This is another different cross-sectional view of the device shown in the aforementioned figure;

[0135] - Figure 10 It is a graph showing the temperature-time development related to the device of the present invention and the prior art devices. Detailed Implementation

[0136] exist Figure 1 The diagram shows the diameter cross-section of the vulcanizing mold 1, which belongs to the equipment used for vulcanizing and molding tires 2.

[0137] Figure 1 Tire 2 is shown only schematically, and the tire mainly comprises a carcass structure having one or more carcass plies. An impermeable layer of elastomeric material, or so-called "liner," is applied inside the one or more carcass plies. Two anchoring ring structures engage with corresponding end flaps of the one or more carcass plies, each of said anchoring ring structures including a so-called bead core, which carries elastomeric filler in a radially outward position. The anchoring ring structures are integrated near an area typically identified by a "bead" 3, where engagement between the tire and the corresponding mounting rim typically occurs. A belt structure, including a belt layer, is circumferentially applied around the one or more carcass plies, and a tread belt 4 is circumferentially stacked on the belt structure. Two sidewalls 5 are applied in laterally opposed positions of the one or more carcass plies, each of said sidewalls extending from the corresponding bead 3 to the corresponding lateral edge of the tread belt 4.

[0138] The vulcanizing mold 1 includes a lower part 6 and an upper part 7 that can be interconnected.

[0139] The lower portion 6 includes a first sidewall plate 8, and the upper portion 7 includes a second sidewall plate 9. The first sidewall plate 8 and the second sidewall plate 9 are axially opposite each other. Each of the first sidewall plate 8 and the second sidewall plate 9 includes a working surface arranged to operate on the bead 3 and sidewall 5 of the paired tire 2. The lower portion 6 and the upper portion 7 are axially movable between a first position, in which the lower portion and the upper portion are spaced apart from each other, and in the second position, the lower portion and the upper portion are connected to each other.

[0140] The vulcanizing mold 1 includes a circumferential portion defined by a plurality of circumferential sectors 10, all of which are arranged around a central axis “YY” of the vulcanizing mold 1. The circumferential sectors 10 are movable between a first position and a second position. In the first position, the circumferential sectors are circumferentially spaced apart from each other and away from the central axis “YY”. In the second position, the circumferential sectors are moved circumferentially closer to each other and closer to the central axis “YY”. In the second position, the circumferential sectors 10, together with a first sidewall plate 8 and a second sidewall plate 9, define a vulcanizing and molding cavity 11 for receiving a tire 2. Figure 6 The shape of the vulcanizing and molding cavity 11 corresponds to the external shape of the tire 2 after molding and vulcanization.

[0141] In the non-limiting example shown in the attached figures, each circumferential sector 10 includes a support block 12 and a working segment 13. Figure 1 and 6 The working section 13 is radially positioned relative to the central axis "YY" inside the corresponding support block 12 and is mounted on the corresponding support block 12 by a connecting device not shown. This allows the working section 13 to be detached and replaced with another working section 13. In this way, the working section 13 can be replaced to vulcanize and mold tires with different sizes and / or different shapes and / or different tread patterns.

[0142] When the working section 13 is installed on the corresponding support block 12, the working section 13 and the support block 12 become one with each other and move together between the first position and the second position.

[0143] In other embodiments not shown, each circumferential sector 10 may be made of only one piece.

[0144] Each working segment 13 includes a working surface 14 ( Figure 1 and 6 The working surface faces radially inward toward the central axis "YY" and is configured to engage with the radially outer portion of the tire 2 when the tire 2 is placed in the vulcanizing and molding cavity 11. In the second position, the mutually approaching working surfaces of the circumferential sectors 10 define circumferential surfaces arranged for operation against the tread strip 4 of the green tire 2 to be vulcanized.

[0145] In the non-limiting embodiment shown in the figure, the circumferential sector 10 is supported by the upper portion 7. Specifically, the circumferential sector 10 is mounted on the guide 15 belonging to the upper portion 7 and configured to move between a first position and a second position.

[0146] In fact, the upper portion 7 includes an annular container 16 having a top 17, a bottom 18, a radially inner surface 19, and a radially outer surface 20. The annular container 16 is coaxial with the central axis “YY” and carries the circumferential sector 10. A guide 15 is positioned on the radially inner surface 19 and formed as a T-rib, which slidably engages in a corresponding T-groove 21 formed in the radially outer portion 22 of the circumferential sector 10. Figure 7 ).

[0147] The radially outer portion 22 of the circumferential sector 10 is disposed on a virtual truncated conical surface, and the radially inner surface 19 of the annular container 16 has a truncated conical shape. Both the virtual truncated conical surface and the radially inner surface 19 taper upwards, and the T-ribs and T-grooves 21 are inclined and converge toward the central axis “YY”.

[0148] The annular container 16 is movable between a raised position and a lowered position. When the annular container 16 moves between the raised and lowered positions, the guide 15 slides within the groove 21.

[0149] In the raised position, the circumferential sector 10 is in the first position, the annular container 16 is above the circumferential sector 10, and the circumferential sector 10 is suspended from the annular container 16.

[0150] In the lowered position, the annular container 16 surrounds the circumferential sector 10, which is in the second position, and the radially inner surface 19 of the annular container 16 contacts the radially outer portion 22 of the circumferential sector 10. Figure 1 and 6 In the lowered position, the circumferential sector is in the second position, and the device defines the vulcanization and molding cavity 11.

[0151] A device, which is known in itself and is not shown, is configured to move the aforementioned components of the device between the aforementioned positions.

[0152] A flexible and elastic membrane 23 (e.g., made of a butyl rubber-based composite) is mounted on the mold 1. The elastic membrane 23 has a pair of radially inner peripheral edges 24, which are provided with anchoring attachments that anchor to a portion of the device, such as... Figure 1As shown, an expandable chamber 25 is defined internally. A generator and / or tank of hot pressurized fluid (not shown as it is of a known type) is operatively connected to the expandable chamber 25 to inflate the elastic membrane 23. A vacuum pump (not shown as it is of a known type) is operatively connected to or may be connected to the expandable chamber 25 to lower the pressure inside the expandable chamber 25 than the pressure outside the expandable chamber 25 and to cause the membrane 23 to collapse / contract.

[0153] The equipment also includes a device operatively associated with the vulcanizing and molding cavity 11 and configured to also apply heat to the tire 2 contained in the vulcanizing and molding cavity 11 by means of a hot, pressurized fluid.

[0154] To preheat the circumferential sector 10 prior to the vulcanization and molding steps, and also to heat the circumferential sector 10 during the vulcanization and molding steps, a conduit 26 for circulating the heating medium is provided in the annular container 16. When the annular container 16 is in the lowered position, the conduit 26 surrounds the circumferential sector 10 and has a wave pattern extending from the top 17 to the bottom 18 of the annular container 16 and from the bottom 18 to the top 17.

[0155] In the diameter section of the annular container 16 ( Figure 1 , 5 (6 and 7), some portions 27 of the conduit 26 are closer to the radial inner surface 19 of the annular container 16 than to the radial outer surface 20 of the annular container 16.

[0156] In the non-limiting embodiment shown in the accompanying drawings, each of these portions 27 is flat and defined by a corresponding U-shaped segment. Two dimensions of the U-shaped segment are much larger than a third dimension, and the third dimension is perpendicular to the radial inner surface 19 of the annular container 16. Figure 3 As shown, each of the U-shaped segments is a groove or recess formed in the radially inner surface 19 of the annular container 16. The groove can be milled into the annular container 16. The groove is formed by a rectangular or trapezoidal plate 28 (in... Figure 3 (The middle part has been removed) closed. The radially inner working surface of plate 28 defines a portion of the inner surface 19 of the annular container 16 and is flush with the rest of the inner surface 19 of the annular container 16. As Figure 7 As shown, each guide 15 is placed between two adjacent plates 28.

[0157] The annular container 16 is made of structural steel (e.g., non-alloy structural steel), and the plate 28 is made of a material with a thermal conductivity between 100 W / (m*K) and 180 W / (m*K) and a hardness between 40 HB and 210 HB. For example, the plate 28 is made of brass or an alloy containing copper, nickel, and silicon (such as CuNi2Si) or an alloy containing copper, tin, zinc, and lead (such as CuSn7Zn4Pb7). The plate 28 allows heat to be transferred from the heating medium to the circumferential sector 10.

[0158] Each U-shaped section includes a lower bend and two upper ends, which are connected by two straight sections. Figure 3 Each of the two upper ends of the U-shaped section is connected to the adjacent U-shaped section via a connecting hole 29, one end of which is connected to the upper end of one of the U-shaped sections and the other end to the upper end of the other U-shaped section. Figure 7 In this case, the connecting hole 29 is formed through the thickness of the annular container 16. For example... Figure 5 As shown, the waveform of the conduit 26 includes a series of U-shaped segments and connecting holes 29, which begin at the inlet 30 and terminate at the outlet 31, following each other in an alternating manner. In other words, the conduit 26 includes multiple top portions and multiple bottom portions that follow each other in an alternating manner. The top portions are defined by the connecting holes 29, the bottom portions are defined by the downward bends of the U-shaped segments, and the top and bottom portions are connected by straight sections of the U-shaped segments. The inlet 30 and outlet 31 are formed on the radially outer surface 20 of the annular container 16 and are close to each other. Figure 2 , 5 and 7).

[0159] like Figure 3 ,and Figure 6 As shown in the diametrical cross-section, each U-shaped segment is defined by a first inner surface 32 parallel to the radial inner surface 19 of the annular container 16, a second inner surface 33 facing the first inner surface 32, and an edge inner surface 34 connecting the first inner surface 32 and the second inner surface 33. In the illustrated embodiment, each of the first inner surface 32 and the second inner surface 33 is U-shaped. The first inner surface 32 and the second inner surface 33 are parallel to each other and identical. The first inner surface 32 is farther from the radial inner surface 19 of the annular container 16 than the second inner surface 33. In the illustrated embodiment, the second inner surface 33 is part of a corresponding plate 28.

[0160] The first inner surface 32 and the second inner surface 33 are spaced apart by a gap "g" (measured perpendicularly to the first inner surface 32 and the second inner surface 33). A first distance "d1" (measured perpendicularly to the first inner surface 32 and the second inner surface 33) from the second inner surface 33 to the radially inner surface 19 of the annular container 16 is the thickness of the plate 28. The area "A1" of the first inner surface 32 is equal to the area of ​​the second inner surface 33. The first inner surface 32 has a height "h", which is parallel to the first inner surface 32 and is measured in the diametrical section of the annular container 16. Figure 3 and 6 The first inner surface 32 has a width "w", which is parallel to the first inner surface 32 or along the circumferential direction of the annular container 16 and orthogonal to the height "h" measured as the width. Figure 3 and Figure 6 The first inner surface 32 is spaced from the radial outer surface 20 of the annular container 16 by a minimum radial distance “d2”. The conduit 26 has an average cross-sectional area, measured perpendicular to the average flow direction of the heating medium inside the conduit 26. The vulcanizing and molding cavity 11 has a maximum inner diameter “D” and a width “C”. Figure 1 ).

[0161] The dimensions of part 27 and related components can be determined as follows: The ratio "A1 / g" of the area "A1" of the first inner surface 32 to the gap "g" is between 1000 mm and 2000 mm. The ratio "A1 / C" of the area "A1" of the first inner surface 32 to the width "C" of the vulcanizing and molding cavity 11 is between 80 mm and 100 mm. The ratio "A1 / d1" of the area "A1" of the first inner surface 32 to the first distance "d1" is between 1000 mm and 2000 mm. The ratio "A1 / d2" of the area "A1" of the first inner surface 32 to the minimum radial distance "d2" is between 100 mm and 200 mm. The ratio "D / d2" of the maximum inner diameter "D" of the vulcanizing and molding cavity 11 to the minimum radial distance "d2" is between 10 mm and 20 mm. The ratio "d2 / d1" of the minimum radial distance "d2" to the first distance "d1" is between 5 and 20. The ratio "h / C" of the height "h" of the first inner surface 32 to the width "C" of the vulcanizing and molding cavity 11 is between 0.7 and 0.9. The ratio "w / C" of the width "w" of the first inner surface 32 to the width "C" of the vulcanizing and molding cavity 11 is between 0.4 and 0.6.

[0162] Due to the aforementioned dimensions, the average velocity of the heating medium within the conduit 26 can be limited to 15 m / s to 25 m / s, optionally 20 m / s, and the flow rate of the heating medium through the conduit can be limited to 4 m³ / s. 3 / s and 8m 3 / s.

[0163] The annular container 16 of the vulcanizing mold 1 also includes a ring 35 connected to the bottom 18 of the annular container 16 to define the bottom 18. The ring 35 may be made of structural steel (e.g., non-alloy structural steel) that follows the circumferential profile of the annular container 16 and has a groove formed in its upper portion. The groove of the ring 35 and the bottom 18 of the annular container 16 together define an annular discharge channel 36 that surrounds a central axis “YY” and is positioned below the conduit 26. Figure 1 , Figure 6 , Figure 8 and Figure 9 The cross-section of ring 35 and discharge channel 36 is shown.

[0164] Multiple discharge holes 37 connect the lower bend of the U-shaped section to the discharge channel 36. Figure 8 The discharge passage 36 shown includes a radial portion 38 connected to the lower bend and an axial portion 39 connecting the radial portion 38 to the discharge passage 36. The outlet opening 40 in the ring 35 allows condensate to be discharged from the discharge passage 36. Figure 8 and 9 ).

[0165] The annular container 16 may also be provided with a heat insulation layer 41 applied to its radial outer surface 20. Figure 1 and Figure 6 ).

[0166] In use, a raw tire 2 is placed in an open vulcanizing mold 1, with the circumferential sector 10 in a first position and the annular container 16 in a raised position. The vulcanizing mold 1 is then closed by lowering the annular container 16 and bringing the circumferential sector 10 to a second position. In the lowered position of the annular container 16, the plate 28 engages with the radially outer portion 22 of the circumferential sector 10, and each circumferential sector 10 is coupled to a pair of said U-shaped segments.

[0167] According to the preheating method of the invention, a heating medium (e.g., steam, preferably water vapor) source is connected to conduit 26, and steam circulates within conduit 26. As the steam passes through the U-shaped section, it flows closer to the circumferential sector 10. The heat of the steam is transferred from the U-shaped section to the circumferential sector 10 through plate 28, heating the circumferential sector 10. The condensate of the steam is discharged from conduit 26 through discharge hole 37 and annular discharge channel 36, and exits discharge channel 36 through outlet opening 40.

[0168] Figure 10The graphs show the temperature T (°C) of the support block 12 in the circumferential sector 10 of the device of the present invention (line A) and the device according to the prior art (line B) as a function of time t (min). Similar to the present invention, the prior art annular container is provided with a conduit formed in the wall and close to the radially outer surface of the annular container. Unlike the present invention, the conduit in the prior art is a single annular conduit, and it is closer to the radially outer surface of the annular container than to the radially inner surface.

[0169] The parameters in Table 1 below apply to the device of the present invention (line A) and the device according to the prior art (line B). The parameters in Table 2 refer to the device of the present invention (line A). The parameters in Table 3 refer to the device according to the prior art (line B).

[0170] Table 1

[0171]

[0172] Table 2

[0173]

[0174] Table 3

[0175]

[0176] Figure 10 The results show that the circumferential sector 10 of the prior art device (B) reaches the final constant temperature (180°C) in 30 minutes, while the circumferential sector 10 of the present invention device (A) reaches the final temperature (185°C) in only 13 minutes.

[0177] Table 4 below shows the calculated simulated steam consumption for the apparatus of the present invention and the apparatus according to the prior art to reach their respective stable temperatures. Steam consumption is reduced by approximately 57%.

[0178] Table 4

[0179]

Claims

1. An apparatus for vulcanizing and molding tires, the apparatus comprising: Multiple circumferential sectors (10) are arranged around a central axis (YY). The multiple circumferential sectors (10) are movable between a first position and a second position. In the first position, the multiple circumferential sectors (10) are circumferentially spaced apart from each other and away from the central axis (YY). In the second position, the multiple circumferential sectors (10) are moved circumferentially closer to each other and closer to the central axis (YY). An annular container (16) having a top (17), a bottom (18), a radially inner surface (19), and a radially outer surface (20); the annular container (16) engages with or is configured to engage with the circumferential sector (10), the annular container (16) being movable between a raised position and a lowered position, in which the circumferential sector (10) is in a first position, and in the lowered position, the annular container (16) surrounds the circumferential sector (10) and the circumferential sector (10) is in a second position; wherein, in the lowered position, the radially inner surface (19) of the annular container (16) contacts the radially outer portion (22) of the circumferential sector (10); When the annular container (16) is in the lowered position and the circumferential sector (10) is in the second position, the device defines a vulcanizing and molding cavity (11) for accommodating the tire (2). The annular container (16) is provided with a conduit (26) for circulating heating medium. When the annular container (16) is in the lowered position, the conduit (26) surrounds the circumferential sector (10). The conduit (26) extends toward the bottom (18) and toward the top (17) in a wave pattern.

2. The device according to claim 1, wherein, In the diametrical cross section of the annular container (16), at least some portions (27) of the conduit (26) are closer to the radial inner surface (19) of the annular container (16) than to the radial outer surface (20) of the annular container.

3. The device according to claim 1 or 2, wherein, The annular container (16) includes a discharge channel (36) connected to the conduit (26).

4. The device according to claim 3, wherein, The discharge channel (36) is annular and surrounds the central axis (YY).

5. The device according to claim 3, wherein, The discharge channel (36) is located below the catheter (26).

6. The device according to claim 3, wherein, The annular container (16) includes at least one discharge port (37) that connects the conduit (26) to the discharge channel (36).

7. The device according to claim 1 or 2, wherein, The conduit (26) includes multiple top portions and multiple bottom portions that follow each other in an alternating manner.

8. The device according to claim 7, wherein, The annular container (16) includes a discharge channel (36) connected to the conduit (26); and wherein the discharge channel (36) is connected to at least one of the plurality of bottom portions.

9. The device according to claim 8, wherein, The discharge channel (36) is connected to all of the bottom portions.

10. The device according to claim 2, wherein, Each of the at least some portions (27) of the catheter (26) has a flat shape.

11. The device according to claim 2, wherein, Each of the at least some portions (27) is defined by a first inner surface (32) parallel to the radial inner surface (19) of the annular container (16), a second inner surface (33) facing and parallel to the first inner surface (32), and an edge inner surface (34) connecting the first inner surface (32) and the second inner surface (33); wherein the first inner surface (32) is farther from the radial inner surface (19) of the annular container (16) than the second inner surface (33).

12. The device according to claim 11, wherein, The ratio of the area (A1) of the first inner surface (32) to the gap (g) between the first inner surface (32) and the second inner surface (33) is between 1000 mm and 2000 mm.

13. The device according to claim 11 or 12, wherein, The ratio of the area (A1) of the first inner surface (32) to the width (C) of the vulcanization and molding cavity (11) is between 80 mm and 100 mm.

14. The device according to claim 11 or 12, wherein, The ratio of the area (A1) of the first inner surface (32) to the first distance (d1) from the first inner surface (32) to the radial inner surface (19) of the annular container (16) is between 1000 mm and 2000 mm; the first distance (d1) is measured perpendicular to the first inner surface (32).

15. The device according to claim 11 or 12, wherein, The ratio of the area (A1) of the first inner surface (32) to the minimum radial distance (d2) from the second inner surface (33) to the radial outer surface (20) of the annular container (16) is between 100 mm and 200 mm.

16. The device according to claim 11 or 12, wherein, The ratio of the maximum inner diameter (D) of the vulcanizing and molding cavity (11) to the minimum radial distance (d2) from the second inner surface (33) to the radial outer surface (20) of the annular container (16) is between 10 and 20.

17. The device according to claim 11 or 12, wherein, The ratio of the height (h) of the first inner surface (32) to the width (C) of the vulcanization and molding cavity (11) is between 0.7 and 0.9; the height (h) is measured in the diameter section of the annular container (16) and parallel to the first inner surface (32).

18. The device according to claim 11 or 12, wherein, The ratio of the width (w) of the first inner surface (32) to the width (C) of the vulcanization and molding cavity (11) is between 0.4 and 0.6; the width (w) is measured along the circumferential direction of the annular container (16).

19. The device according to claim 11 or 12, wherein, The catheter (26) includes a plurality of top portions and a plurality of bottom portions that follow each other in an alternating manner; and wherein, viewed in the radial direction, each of the at least some portions (27) is a U-shaped segment of the catheter (26); wherein the lower bend of the U-shaped segment is one of the plurality of bottom portions of the catheter (26), and wherein each of the two upper ends of the U-shaped segment is connected to an adjacent U-shaped segment through one of the plurality of top portions.

20. The device according to claim 2, wherein, Each of the at least some portions (27) of the conduit (26) is defined by a groove formed in the radial inner surface (19) of the annular container (16) and a plate (28) that closes the groove; wherein, in the lowered position, the plate (28) engages with the radial outer portion (22) of the circumferential sector (10).

21. The device according to claim 20, wherein, The plate (28) is made of a material with a thermal conductivity between 100 W / (m*K) and 180 W / (m*K) and a hardness between 40 HB and 210 HB.

22. The device according to claim 2, wherein, When the annular container (16) is in the lowered position, each circumferential sector (10) is coupled to a plurality of the portions (27).

23. The device according to claim 1 or 2, wherein, The conduit (26) has an inlet (30) and an outlet (31) formed on the radial outer surface (20) of the annular container (16) and close to each other.

24. The device according to claim 1 or 2, wherein, Each of the circumferential sectors (10) includes a support block (12) and a working section (13), the support block (12) including the radially outer portion (22), the working section (13) being mounted on the support block (12) and including a working surface (14) configured to engage the tire (2) placed in the vulcanization and molding cavity (11).

25. A method for preheating a circumferential sector in an apparatus for vulcanizing and molding tires, the method comprising: An annular container (16) is provided, which is positioned around a plurality of circumferential sectors (10) arranged around a central axis (YY) or configured to be positioned around a plurality of circumferential sectors arranged around a central axis, the plurality of circumferential sectors (10) defining vulcanization and molding cavities (11). The heating medium is made to flow through a waveform pattern formed in the annular container (16), the waveform pattern extending from the top (17) to the bottom (18) and from the bottom (18) to the top (17) of the annular container (16). The radial inner surface (19) of the annular container (16) contacts or is configured to be in contact with the radial outer portion (22) of the circumferential sector (10).

26. The method of claim 25, wherein the method comprises: The heating medium flows closer to the radial inner surface (19) of the annular container (16) rather than the radial outer surface (20) of the annular container (16).

27. The method according to claim 25 or 26, wherein, The average velocity of the heating medium in the waveform section is between 15 m / s and 25 m / s.

28. The method according to claim 25 or 26, wherein, The flow rate of the heating medium passing through the waveform section is between 4m³ / s. 3 / s and 8m 3 Between / s.

29. The method according to claim 25 or 26, wherein, The heating medium is steam, and the method further includes: discharging a condensate portion of the steam from the waveform section.

30. The method according to claim 29, wherein, The steam is discharged while it is flowing through the waveform section.

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