WO2015116175A1

WO2015116175A1 - Continuous autoclave with curing chamber

Info

Publication number: WO2015116175A1
Application number: PCT/US2014/014191
Authority: WO
Inventors: Metodi L Ikonomov; David Chan Wah LUNG; Adib T. Chebli
Original assignee: Compagnie Generale Des Etablissements Michelin; Michelin Recherche Et Technique S.A.
Priority date: 2014-01-31
Filing date: 2014-01-31
Publication date: 2015-08-06

Abstract

Methods for curing tires, and corresponding systems and tires formed thereby include providing a system for curing retreaded tires, the system including a series of chambers. Such methods also include providing an unbonded retreaded tire, placing the unbonded retreaded tire into an input chamber, sealing the input chamber, conveying the unbonded retreaded tire from the input chamber, sealing a curing chamber among the series of chambers, pressurizing the curing chamber to a target curing pressure, heating the curing chamber to a target curing temperature, curing the unbonded retreaded tire in the curing chamber to form a cured tire, unsealing the curing chamber to a removal chamber among the series of chambers, conveying the cured tire from the curing chamber to the removal chamber, depressurizing the removal chamber, unsealing the removal chamber; and removing the cured tire therefrom.

Description

CONTINUOUS AUTOCLAVE WITH CURING CHAMBER

BACKGROUND OF THE INVENTION

Field of the Invention

[0001] This invention relates generally to methods and apparatus for manufacturing retreaded tires, and treads for retreading tires. More specifically, this invention relates to methods and apparatus for curing a retreaded tire in a continuous autoclave of singular structure having a series of sealable chambers that can be individually pressurized, heated, and isolated from an external environment.

Description of the Related Art

[0002] A retreaded tire consists of a new pre-cured tread attached to a pre-existing tire carcass. The tire carcass is prepared to receive the new pre-cured tread by removing the prior tread, such as through buffing or abrading operations. The new pre-cured tread is then applied to the tire carcass with a bonding layer comprising bonding material to secure the new tread to the carcass. Subsequently, in some techniques, a flexible curing membrane (or envelope) is arranged at least partially around the tire to create a sealed fluid chamber between the curing membrane and the tire. The combination of a retreaded tire with an installed curing membrane is referred to herein as a tire-membrane assembly.

[0003] In operation, multiple tire-membrane assemblies are placed in batches within a tire curing chamber, such as an autoclave. Each tire-membrane assembly is then placed in fluid communication with a vacuum source. The vacuum source substantially removes gas between the tire and the curing membrane. Subsequently, while under vacuum pressure, the curing chamber is also heated and positively pressurized, such that a pressure force is applied to the flexible curing membrane. Because these operations have traditionally been performed in batches of multiple tires, single tires of the batch cannot be reached, and the autoclave cannot be opened, without disrupting operation on the entire batch. Further, pressure and heat in the autoclave are lost each time the autoclave is opened between batches.

[0004] Thus, single-chamber autoclaves utilizing batch-type processes can lead to inefficiency and wasted energy in terms of released pressure or lost heat when the inside of an autoclave is accessed. Therefore, there is a need to improve the retreading process by permitting curing of smaller groups and access to individual tires among the groups without exposing an entire portion of the autoclave (e.g., curing chamber) to an open-air environment. It is also desirable to retain energy between batches of tires rather than completely re- pressurize and reheat curing (and/or degassing) chambers.

SUMMARY OF THE INVENTION

[0005] Particular embodiments of the invention concerns methods for curing tires, and corresponding systems and tires formed thereby. One embodiment of such methods includes providing a system for curing retreaded tires, the system including a series of chambers. Such methods also include providing an unbonded retreaded tire, placing the unbonded retreaded tire into an input chamber, sealing the input chamber from an external environment using an input door, conveying the unbonded retreaded tire from the input chamber, sealing a curing chamber among the series of chambers, pressurizing the curing chamber to a target curing pressure based at least in part on a curing operation for the unbonded retreaded tire, heating the curing chamber to a target curing temperature based at least in part on a curing operation for the unbonded retreaded tire, curing the unbonded retreaded tire in the curing chamber to complete the curing operation on the unbonded retreaded tire producing a cured tire, unsealing the curing chamber to a removal chamber among the series of chambers, conveying the cured tire from the curing chamber to the removal chamber, depressurizing the removal chamber based at least in part on an environmental pressure or an environmental temperature of the external environment, unsealing the removal chamber from the external environment using a removal door; and removing the cured tire from the removal chamber.

[0006] In another embodiment, the invention comprises a system for curing an unbonded retreaded tire, which comprises a pre-cured tread arranged annularly around an outer circumference of an annular tire carcass with a bonding layer comprising uncured bonding material arranged between the pre-cured tread and the annular tire carcass, the unbonded retreaded tire having a thickness extending between inner and outer sides of the unbonded retreaded tire, where the annular tire carcass comprises a pair of sidewalk spaced apart in an axial direction of the tire, each of the pair of sidewalk extending radially inward from an undertread portion to a bead portion. The system comprises a series of chambers, the series of chambers being interconnected and sealed from an external environment when an input door and a removal door are closed; a conveyor component that conveys the unbonded retreaded tire between two or more of the series of chambers; a sealable input chamber of the series of chambers having the input door; a sealable curing chamber of the series of chambers that performs a curing operation on the unbonded retreaded tire; a pressure source that pressurizes at least the curing chamber to one or more target curing pressures based at least in part on the unbonded retreaded tire in accordance with the curing operation; a heating element that heats at least the curing chamber to one or more target curing temperatures based at least in part on the unbonded retreaded tire in accordance with the curing operation; a sealable removal chamber of the series of chambers having the removal door; and a plurality of inter-chamber interfaces to effect sealing of at least the input chamber, the curing chamber, and the removal chamber from another chamber among the series of chambers.

BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Fig. 1 is a view of a linear continuous tire curing system in accordance with an embodiment invention.

[0008] Fig. 2A is a view of an annular continuous tire curing system in accordance with an embodiment of the invention.

[0009] Fig. 2B is an additional view of the annular continuous tire curing system in accordance with an embodiment of the invention.

[0010] Fig. 3 is an exploded view of a tire-membrane assembly in accordance with an embodiment of the invention.

[0011] Fig. 4 is an assembled view of an unbonded retreaded tire in a tire-membrane assembly in accordance with an embodiment of the invention.

[0012] Fig. 5 is a perspective view of an unbonded retreaded tire in a tire-membrane assembly in accordance with an embodiment of the invention.

[0013] Fig. 6 illustrates a view of a controller for use controlling or automating one or more aspects of the invention.

DETAILED DESCRIPTION OF PARTICULAR EMBODIMENTS

[0014] Particular embodiments of the invention provide retreaded tires and methods for forming a retreaded tire.

[0015] Disclosed in this application are embodiments of a method for curing tires. An embodiment of the method begins by providing a system for curing retreaded tires, the system including a series of chambers. As used herein, a "chamber" is any enclosed volume isolatable from an external environment by closing doors or interfaces of the chamber. Chambers can include various openings, connectors, sources and sinks to control conditions within the chamber. For example, chambers can have apertures configured to permit airflow in or out to modify air pressure within the chamber. This permits the inside of a chamber being placed under vacuum or elevated pressure.

[0016] Various embodiments of the method further include providing an unbonded retreaded tire, which comprises a pre-cured tread arranged annularly around an outer circumference of an annular tire carcass with a bonding layer comprising uncured bonding material arranged between the pre-cured tread and the annular tire carcass, the unbonded retreaded tire having a thickness extending between inner and outer sides of the unbonded retreaded tire, where the annular tire carcass comprises a pair of sidewalk spaced apart in an axial direction of the tire, each of the pair of sidewalk extending radially inward from an undertread portion to a bead portion. In particular embodiments, a retreaded tire can be provided pre-assembled, such as when a carcass, bonding material, and tread are already coupled prior to beginning the aspects herein. Alternatively, assembling the carcass, bonding layer, tread, and other embodiments can comprise an aspect herein.

[0017] In some embodiments the method additionally includes placing the unbonded retreaded tire into an input chamber. The method further includes sealing the input chamber from an external environment using an input door in particular embodiments. Thereafter, conveying the unbonded retreaded tire from the input chamber can be completed in some embodiments. Conveying tires in-process can be done using a conveying system or component. Attachment members can retain at least a portion of a tire in-process, or a structure attached thereto (e.g., a wheel or rim or any other mount) to couple a tire in-process with the means of conveying the tires through a continuous autoclave having multiple sealable chambers.

[0018] The method also includes sealing a curing chamber among the series of chambers in some embodiments. Sealing of this chamber or others can include closing the chamber from an external environment and other chambers such that no airflow in or out is permitted, except for an aperture configured to facilitate pressurization or vacuum pressure of the chamber, or as used with a heating element. Thus, after sealing is completed, the chamber is fluidly sealed from other chambers and the external environment. In embodiments, sealing can also include the positioning of thermal insulation (e.g., as a part of a door or partition).

[0019] In particular embodiments, the method additionally includes pressurizing the curing chamber to a target curing pressure based at least in part on a curing operation for the unbonded retreaded tire. One or more compressors, or other devices or techniques for modifying pressure in a sealed chamber, can be utilized. Heating the curing chamber to a target curing temperature based at least in part on a curing operation for the unbonded retreaded tire is performed in specific embodiments, and can be conducted before, after, or concurrently with pressurization. One or more heating elements can be utilized to effect such conditions in the chambers.

[0020] Curing the unbonded retreaded tire in the curing chamber to complete the curing operation on the unbonded retreaded tire producing a cured tire is performed thereafter in some embodiments. Curing the tire comprises at least maintaining the tire in the sealed chamber at one or more temperatures and one or more pressures for one or more periods of time (e.g. , performing a curing recipe).

[0021] Curing processes in embodiments of the method described can be performed with or without a curing membrane. A curing membrane herein can be flexible, sized to one or more tires (e.g., diameter, width), and otherwise appropriate (e.g. , material, thickness, flexibility) for intended purposes on one or more tire sizes. In at least one embodiment, a flexible curing membrane can also be a flexible degassing membrane. In at least one alternative embodiment, the flexible curing membrane is a different membrane than that provided for degassing.

[0022] Generally, curing chambers (and optionally, degassing chambers described below) provide a controlled environment where a tire is degassed or bonded, respectively, in accordance with a recipe or formula identifying any combination of one or more pressures and temperatures for certain durations. It is appreciated that degassing and bonding operations can be performed within one or more degassing and/or curing chambers. It is also appreciated that the same or different chambers can be used for degassing and bonding.

[0023] After a curing process is completed on one or more tires in the curing chamber, the method additionally includes unsealing the curing chamber to a removal chamber among the series of chambers. Once the curing chamber is unsealed, the tire can advance, and conveying the cured tire from the curing chamber to the removal chamber is completed.

[0024] Once the tire arrives in the removal chamber, and, in embodiments, the removal chamber is sealed from the curing chamber, the method additionally comprises depressurizing the removal chamber based at least in part on an environmental pressure or an environmental temperature of the external environment in particular embodiments. Depressurizing the removal chamber can be an inherent function of a removal door, or express function of one or more other components. For example, a control or release valve can route pressure (and/or heat) through an outlet or vent to direct pressure and heat in a safe or desirable direction. In specific embodiments, such aspects can be used in providing a fluid communication connection between two or more chambers among the series of chambers and equalizing pressure between the two or more of the series of chambers before unsealing any of the two or more chambers. In alternative embodiments, no such components are utilized, and unsealing of a removal door permits safe decompression of the removal chamber.

[0025] Unsealing the removal chamber from the external environment using a removal door and removing the cured tire from the removal chamber are performed in some embodiments to complete the method described above.

[0026] In particular embodiments, a degassing operation can be performed separately from the curing operation. In such embodiments, the method can also include sealing a degassing chamber among the series of chambers. After sealing the degassing chamber, the method can complete pressuring the degassing chamber to a target degassing pressure based at least in part on a degassing operation for the unbonded retreaded tire, which accomplishes degassing the unbonded retreaded tire in the degassing chamber to complete the degassing operation on the unbonded retreaded tire. Subsequent aspects to provide a degassed unbonded tire for curing include unsealing the degassing chamber to the curing chamber and conveying the unbonded retreaded tire from the degassing chamber to the curing chamber.

[0027] A flexible degassing membrane herein is sufficiently sized for its intended purpose in forming one or more vacuum chambers along at least the outer side of the tire. For example, a membrane may extend substantially around the entire tire, the membrane comprising one or more sections. By further example, the unbonded retreaded tire may be mounted on a mount, such as a wheel, for example, and one or more degassing membranes arranged to extend from the mount and about assembled retread tire and the tread arranged thereon. In such example, a flexible degassing membrane extends along the top side of the tire tread and down each of the pair of tire carcass sidewalls to engage the mount, forming a sealed fluid chamber between the membrane and the tire along the tread and sidewalls. In certain embodiments, the degassing membrane may be a membrane used or designed for curing in embodiments where a degassing assembly is not disassembled prior to curing.

[0028] Various membrane assemblies can be assembled at different positions within or outside a continuous autoclave in various embodiments. For example, in some embodiments, a degassing and/or curing membrane can be assembled before the tire is placed within an autoclave. In alternative embodiments, assembly occurs in an input chamber, or after the tire enters a degassing chamber and is sealed from the input chamber. In embodiments where a curing membrane used is different from a degassing membrane (if any), the curing membrane may be separately assembled after a degassing operation, in a degassing chamber, in a curing chamber, or at other appropriate locations.

[0029] In some embodiments of methods utilizing continuous, multi-chamber autoclaves, one or more chambers can be multi-function. For example, there is at least one embodiment where the degassing chamber is the input chamber. Additionally, there can be some embodiments where the curing chamber is the removal chamber. In such embodiments, methods can include pressurizing the input chamber based at least in part on the target degassing pressure.

[0030] Chambers such as an input chamber, curing chamber, and removal chamber, and optionally a degassing chamber or others, can be separated by partitions that are openable or unsealable to permit conveyance of a tire in-process between chambers. Further, the input chamber and removal chamber can be isolated from an external environment using an input door and a removal door. Systems and methods herein can, in some embodiments, limit the number of partitions opened at one time to prevent any chamber being open to two adjacent chambers, or an adjacent chamber and an external environment, simultaneously. In this fashion, the loss of pressure or heat can be minimized while still permitting tires in-process to be accessed individually or in batches smaller than the yield of the entire autoclave.

[0031] Further, efficiency can be increased by employing particular embodiments where the conveying is executed at high speed to limit a loss of at least one of pressure or heat between the series of chambers. Particularly where the partition between a larger chamber (e.g., a curing chamber) and smaller chamber (e.g., removal chamber) is opened, a fast transition between the chambers can preserve heat or pressure in a chamber where it must be restored to elevated quantities for subsequent operations.

[0032] Embodiments of the innovation disclosed herein further include apparatuses for performing the method described above, and bonded retreaded tires produced using the method described above.

[0033] As used herein, "vacuum" and "under vacuum" mean providing a fluid pressure equal to substantially zero psia (pounds per square inch absolute), and "substantial vacuum" or "substantially under vacuum" means 5 to 0 (zero) psia. "Partial vacuum" connotes a pressure less than 14.7 psia, less than 10 psia, less than 8 psia, less than 5 psia, or less than 3 psia. Additional aspects of such methods may further include connecting a fluid passage to the curing membrane of the tire-membrane assembly to place the sealed fluid chamber in fluid communication with a pressurization source (configured to provide positive pressure and/or vacuum pressure as needed). A pressurization source may comprise a compressor or any other device known to one of ordinary skill in the art. While aspects herein are described as one or more separate vacuum and pressure sources, it is understood that such pressure or vacuum can be provided by a single pressurization source in some embodiments.

[0034] Particular embodiments of systems associated with the methods discussed above will now be described in further detail below in association with the figures filed herewith exemplifying the performance of the methods in association with particular embodiments of the tread.

[0035] Turning now to Fig. 1, a linear continuous tire curing system 100 is shown. Linear continuous tire curing system 100 includes linear continuous autoclave 110 having a series of chambers separated by inter-chamber partitions 119 and closed by doors on opposite ends. Specifically, unbonded retreaded tire 121A is placed into input chamber 111 of linear continuous autoclave 110 through input door 115. Unbonded retreaded tire 121A can be coupled with attachment member 118, which retains unbonded retreaded tire 121A during curing and/or other operations (e.g. , degassing) performed in linear continuous autoclave 110. Attachment member 118 is in turn movably coupled with conveyor component 117, which conveys unbonded retreaded tire 121A (and/or other tires) through the chambers of linear continuous autoclave 110. [0036] Once unbonded retreaded tire 121A is placed onto attachment member 118 in input chamber 111, input door 115 can be closed to seal input chamber 111 from an external environment. Unbonded retreaded tire 121A can advance in input chamber 111 until a subsequent process (e.g. , degassing, curing) is complete in an adjacent chamber. Alternatively, an inter-chamber partition 119 can be opened immediately to convey unbonded retreaded tire 121A to a subsequent chamber. In additional alternative or complementary embodiments, input chamber 111 can be pressurized, heated, or have other parameters modified based on an adjacent chamber before inter-chamber partition 119 is opened. In still further embodiments, input chamber 111 can be pressurized or heated to facilitate one of a degassing or curing operation to be performed in input chamber 111.

[0037] In the illustrated embodiment, after leaving input chamber 111, unbonded retreaded tire 121B is sealed in degassing chamber 112. In the illustrated embodiment, degassing membrane 131 surrounds at least a portion of unbonded retreaded tire 121B, and facilitates degassing of the tire as described below.

[0038] Sealed degassing chamber 112 can be pressurized via degassing pressure aperture 133, coupled to a pressure source, to facilitate degassing operations. Further, various pressure or vacuum sources (not shown) can act on degassing membrane 131 and/or associated degassing components (e.g., inflatable bladder inside the carcass of unbonded retreaded tire 121B) via degassing pressure aperture 133 or other interfaces. In specific embodiments, degassing can optionally be performed at a specific temperature which can be effected at least in part using degassing heating element 132.

[0039] In embodiments, prior to beginning a degassing operation in degassing chamber 112, degassing membrane 131 may be applied to unbonded retreaded tire 121B. Such arrangement of degassing membrane 131 and associated components can be performed automatically. Alternatively, in some embodiments, unbonded retreaded tire 121B is previously assembled with a degassing membrane 131. Further, degassing membrane 131 may be automatically removed prior to performing curing operations on unbonded retreaded tire 121B.

[0040] After degassing is complete in degassing chamber 112 (or, immediately after leaving input chamber 111 in embodiments not including degassing chamber 112), an inter- chamber partition 119 of curing chamber 113 is opened to permit conveyance into curing chamber 113. One or more curing retreaded tires 121C can proceed through curing chamber 113 to undergo a curing operation.

[0041] Curing operations can be conducted at a curing pressure and curing temperature. Curing chamber 113 includes curing heating element 141 and curing pressure aperture 142 which can cause curing chamber 113 to rise to appropriate temperatures and pressures to cure curing retreaded tires 121C. In embodiments, curing can be performed with a curing membrane (not illustrated) covering at least a portion of curing retreaded tires 121C. In such embodiments, various pressure or vacuum sources (not illustrated) can be operably coupled with at least one of the curing membrane and curing retreaded tires 121C to increase or decrease pressure in the curing membrane or related components (e.g., inflatable bladder inside the carcass of curing retreaded tires 121C, not pictured). In various embodiments utilizing a degassing chamber 112 as shown, the curing membrane can be the same membrane previously used during the degassing operation, or a new membrane may be provided and arranged about curing retreaded tires 121C. In alternative embodiments, no membrane is used in conjunction with curing retreaded tires 121C in curing chamber 113.

[0042] After a curing operation is completed on one or more of curing retreaded tires 121C, partition 119 between the curing chamber and removal chamber can be opened to convey bonded retreaded tire 121D into removal chamber 114. In embodiments, removal chamber 114 can be pressurized and/or heated prior to opening partition 119 between curing chamber 113 and removal chamber 114. In embodiments utilizing a curing membrane (not pictured), the curing membrane may be removed in curing chamber 113, removal chamber 114, or after leaving linear continuous autoclave 110.

[0043] Once bonded retreaded tire 12 ID is conveyed to removal chamber 114 and partition 119 between removal chamber 114 and curing chamber 113 is re-sealed, removal chamber 114 can be depressurized to equalize the pressure (or reduce a pressure difference) between the external environment and removal chamber 114. Thereafter, bonded retreaded tire 121D can be removed from linear continuous autoclave 110 by opening removal door 116. In embodiments, removal chamber 114 can be cooled or depressurized, using a release or control valve or other component, prior to opening removal door 116.

[0044] Linear continuous tire curing system 100 can further include control system 150. Control system 150 can control one or more parameters of linear continuous autoclave 110. For example, control system 150 can manage: opening and closing of input door 115 and removal door 116; sealing and unsealing of inter-chamber partitions 119; rate of movement of conveyor component 117; pressure and temperature in at least curing chamber 113, and, in embodiments including such, degassing chamber 112; assembly or disassembly of degassing membrane 131 and/or a curing membrane, and/or associated components; pressure or vacuum provided to degassing membrane 131 and/or a curing membrane, and associated components; attachment or detachment of attachment member 118; and various other functions. Control system 150 can include pre-programmed parameters for operating linear continuous autoclave 110 in accordance with various recipes to complete curing on tires of particular specifications (e.g. , dimensions, materials, uses). Further, control system 150 can provide monitoring and notifications related to the operation of linear continuous autoclave 110, and log statistics or event data associated with the same.

[0045] Turning now to Figs. 2A and 2B, two views of an annular continuous tire curing system 200 is shown at different points in time. Annular continuous tire curing system 200 includes annular continuous autoclave 210 having access chamber 211 providing combined tire input and removal functionality. Annular continuous autoclave 210 functions similarly to linear continuous autoclave 110, having a plurality of chambers that are fluidly isolatable from one another and an outside environment. Due to its rotating configuration, annular continuous autoclave 210 can repeatedly convey tires through any of its chambers without exposure to an exterior environment to place a specific tire in access chamber 211 for access without having to first go through a first-in-first-out cycle completion. Thus, for example, defective tires can be removed immediately, freeing the space for another tire, and avoiding expenditure of energy on an undesirable tire. In another example, specific tires may be cured for different times without interrupting other production. In embodiments, the tires of annular continuous autoclave 210 can be rotated in one or both of clockwise and counterclockwise (in reference to the overhead view provided).

[0046] Turning to the arrangement of annular continuous autoclave 210, access chamber 211 is separated from degassing chamber 212 and curing chamber 213 by two inter- chamber partitions 219. The inside of annular continuous autoclave 210 is accessed via access door 215 of access chamber 211. Unbonded retreaded tire 221 is loaded into annular continuous autoclave 210 through access chamber 211. [0047] Degassing chamber 212 receives unbonded retreaded tire 222 in Fig. 2A. After sealing partition 219 from access chamber 211, and ensuring degassing chamber 212 is isolated from curing chamber 213, a degassing operation can be completed on unbonded retreaded tire 222 in degassing chamber 212. In alternative embodiments, annular continuous autoclave 210 need not include degassing chamber 212.

[0048] After completing the degassing operation in degassing chamber 212 (or, after sealing access chamber 211 in embodiments not including degassing chamber 212), inter- chamber partition 219 sealing curing chamber 213 can be unsealed. Unbonded retreaded tire 222 can then be conveyed into curing chamber 213. Thereafter, curing chamber 213 is sealed, and a curing operation is performed. Curing retreaded tires 223A, 223B, 223C, 223D, and 223E, shown in curing chamber 213, can either remain static or be conveyed through curing chamber 213 during the curing process.

[0049] After one or more of curing retreaded tires are cured to become bonded tires, the bonded tires can be conveyed singly or as a batch to access chamber 211. In some embodiments access chamber 211 can be decompressed and/or cooled prior to opening access door 214. Bonded tires or others can be removed via access door 215. Additional unbonded retreaded tires 221 can be loaded into access chamber thereafter, or between removing tires, without disrupting the activity of other chambers.

[0050] While Figs. 2 A and 2B do not illustrate degassing or curing membranes applied to one or more unbonded retreaded tires 221 and/or 222 (e.g., like degassing membrane 131), it is understood that such aspects can be employed with annular continuous tire curing system 200 without departing from the scope or spirit of the innovations disclosed.

[0051] Annular continuous tire curing system 200 can further include control system 250. Control system 250 can control one or more parameters of annular continuous autoclave 210. For example, control system 250 can manage: opening and closing of access door 215; sealing and unsealing of inter-chamber partitions 219; rate of movement of unbonded retreaded tires 221 and 222, and/or curing retreaded tires 223A, 223B, 223C, 223D, and 223D; pressure and temperature in at least curing chamber 213, and, in embodiments including such, degassing chamber 212; assembly or disassembly of degassing membrane 231 and/or a curing membrane, and associated components; pressure or vacuum provided to degassing membrane and/or a curing membrane, and associated components; and various other functions. Control system 250 can include pre-programmed parameters for operating annular continuous autoclave 210 in accordance with various "recipes" to complete curing on tires of particular specifications and dimensions. Further, control system 250 can provide monitoring and notifications related to the operation of annular continuous autoclave 210, and log statistics or event data associated with the same.

[0052] FIG. 2B in particular shows unbonded retreaded tires 221 and 222, and curing retreaded tires 223A, 223B, 223C, 223D, and 223E rotated into different positions within annular continuous autoclave 210. In this way, curing retreaded tire 223D is in access chamber 211, and it is unnecessary to remove other tires from annular continuous autoclave 210 (or the pressurized environment therein) to access a specific tire such as curing tire 223D.

[0053] In specific embodiments of autoclave systems 100 and 200, two or more chambers can be placed in fluid communication utilizing a line, pipe, aperture, or other fluidly connective portion (not pictured) permitting airflow between the chambers while partitions 119, input door 115, and removal door 116 are sealed. The fluidly connective portion can include valves at one or more chambers, or centrally there between, which can be openable or closeable to equalize or transfer heat and energy between chambers. In this fashion, a chamber to be opened or decompressed can transfer a portion of its pressure and heat to another chamber rather than surrender its energy to an external environment.

[0054] For example, removal chamber 114 can be sealed containing bonded retreaded tire 121D for removal. Input chamber 111 in turn is sealed with unbonded retreaded tire 121A preparing to advance to degassing chamber 112. Input chamber 111 is at a pressure and temperature substantially similar to that of the external environment, and removal chamber 114, having recently been open to the atmosphere of curing chamber 113, is at a pressure and temperature substantially similar to that of curing chamber 113. To avoid wasting the pressure and heat contained in removal chamber 114 when removal door 116 is to be opened, a fluidly connective portion (not pictured) between removal chamber 114 and input chamber 111 can be opened, allowing the two chambers to equalize and raising the pressure and temperature of input chamber of 111. In this fashion, less energy must be spent bringing input chamber 111 or subsequent chambers to pressure or temperature for degassing and/or curing operations, or to raise chamber pressure or temperature to the specified quantity after unsealing. The fluidly connective portion can be closed prior to opening removal door 116 to prevent escape of pressure or heat from input chamber 111, which is now at a higher pressure and temperature than the external environment to which removal chamber 114 will be opened.

[0055] While various chambers depicted in Figs. 1 and 2 are shown as containing a particular number of tires, it is understood that chambers can contain or operate on batches one or multiple tires in accordance with the disclosures herein.

[0056] Various embodiments of linear continuous autoclave 110, annular continuous autoclave 210, or other autoclaves described herein can include other aspects in furtherance of the processes and techniques described above. For example, linear continuous autoclave 110 and/or annular continuous autoclave 210 can be of monolithic construction or be surrounded by a monolithic or multipart shell to provide for singular, continuous construction and/or full sealing from an external environment. Other components or techniques, such as the integration of additional doors allowing direct access to individual chambers among the series of chambers, partitioning chambers shown as a single chamber into multiple chambers (e.g. , two or more curing chambers), and so forth, are embraced under the disclosures herein.

[0057] Further still, in at least one embodiment of linear continuous autoclave 110 and/or annular continuous autoclave 210 a moving chamber can be employed. For example, a tire can be placed in a moving chamber whereby the chamber moves with the tire to multiple stations within linear continuous autoclave 110 and/or annular continuous autoclave 210 and utilizes interfaces or equipment at each station to perform all aspects related to tire curing without unsealing the tire from the movable chamber.

[0058] With respect to Figs. 3-5, embodiments of assemblies including at least tire- membrane assembly 300 is shown. With reference to Fig. 3, various components of tire- membrane assembly 300 are shown prior to assembly, while Figs. 4 and 5 show tire- membrane assembly 300 in an assembled arrangement in accordance with an exemplary embodiment. Fig. 4 particularly shows tire-membrane assembly 300 in operation chamber 400.

[0059] In particular, tire-membrane assembly 300 includes (assembled) unbonded retreaded tire 320 mounted on wheel 310 (more generally representing a mount for the tire). Unbonded retreaded tire 320 is surrounded by membrane 330, and, in combination, unbonded retreaded tire 320 and membrane 330 form first vacuum chamber 351 and second vacuum chamber 352.

[0060] Unbonded retreaded tire 320 includes at least tire carcass 321, bonding layer 322, and tread 323. Bonding layer 322 can include one or more uncured bonding materials disposed between tire carcass 321 and tread 323. Tread 323 can be a pre-cured tread arranged annularly around an outer circumference of an annular tire carcass. In embodiments, unbonded retreaded tire 320 can be provided preassembled (e.g., tire carcass 221, bonding layer 222, and tread 223 coupled when provided). Alternatively, additional aspects associated with forming, degassing, or curing unbonded retreaded tire 220 comprise assembling the individual components provided separately.

[0061] Wheel 310 can be specially configured for degassing and/or curing operations. For example, wheel 310 can include a pressure interface 311 adapted to permit filling of inflatable bladder 337. In specific embodiments, more than one inflatable bladder can be used, separately or in conjunction with inflatable bladder 337. Additionally, rim flanges can be adapted for use with unbonded retreaded tire 320 and membrane 330. For example, one or both rim flanges can be configured to provide specialized support for a tire bead, or facilitate airtight securing of membrane 330. In alternative embodiments, wheel 310 can be a wheel typically used in operation with the tire type of unbonded retreaded tire 320, and standard aspects (e.g., wheel air valve) can be adapted for use in degassing and/or curing operations.

[0062] For purposes of integrating tire-membrane assembly 300 with linear continuous autoclave 110 and/or annular continuous autoclave 210, wheel 310 or other portions of tire-membrane assembly 300 can be coupled with attachment member 118 Unbonded retreaded tire 320 is surrounded by membrane 330, and in combination unbonded retreaded tire 320 and membrane 330 form first vacuum chamber 351 and second vacuum chamber 352.

[0063] To facilitate simple mounting and disassembly, wheel 310 can be of two-part constraction including first wheel half 310A and second wheel half 310B. First wheel half 310A and second wheel half 310B can connect by any appropriate means and can be configured to accommodate an inflatable bladder between wheel 310 and an inner cavity of tire carcass 321. Further, wheel 310 can be arranged for connecting with an attachment member (e.g., attachment member 118) or for other handling means. [0064] With continued reference to Figs. 3-5, membrane 330 is sized for use with a plurality of different sized tires (i.e. , unbonded retreaded tire 320) and configured to be arranged about unbonded retreaded tire 320 such that first vacuum chamber 351 and second vacuum chamber 352 are sealed and capable of maintaining at least partial vacuum pressure.

[0065] As noted herein, membrane 330 can comprise a plurality of portions. In the illustrated embodiments, membrane 330 includes at least first membrane portion 331 and second membrane portion 332. In alternative embodiments, first membrane portion 331 and/or second membrane portion 332 can be secured to wheel 310 using a rim attachment component, which sealably couples one or both of first membrane portion 331 and second membrane portion 332 to a rim or edge of wheel 210. Rim attachment components can ensure a fluid seal between degassing membrane 230 and impermeable portions of the rim where a multi-part degassing membrane includes discontinuities at such locations.

[0066] While each of first membrane portion 331 and second membrane portion 332 may be configured to extend at least partially across an entire lateral side of a tire, first membrane portion 331 is configured to extend across an entire lateral side of the tire and wheel while the second membrane portion 332 is configured to extend partially across a second lateral side of the tire and wheel. In particular, the second membrane portion 332 is configured to extend from an outer circumference of the tire to at least a circumferential portion of the lateral side of the wheel to allow a wheel support 360 (as illustrated in Fig. 4) to access to the wheel to which it is operably attached. It is appreciated that either of first membrane portion 331 and second membrane portion 332 may in turn be formed of multiple separate portions (e.g. , second membrane portion 332 in two portions as-depicted).

[0067] First membrane portion 331 and second membrane portion 332 meet at sealing junction 338. Sealing junction 338 may comprise a joint, an overlap, or a pleat, for example. It is understood that terminal edges of the degassing membrane include terminal edges of different portions of the membrane. Sealing junction 338 may not be properly established until the one or more vacuum chambers are placed under vacuum or partial vacuum.

[0068] As discussed above, the curing membrane is configured to be sufficiently sealed to maintain at least partial vacuum pressure within the vacuum chamber. In the embodiment shown, sealing structures 340A and 340B are employed alone or in combination with to form sealing junction 338 between first membrane portion 331 and second membrane portion 332, whereby the sealing structures force the first and second lateral portions into contact. The embodiment shown also includes sealing structures 341A and 341B, which are also employed to force the first membrane portion 331 and second membrane portion 332 respectively against wheel 310. In lieu of sealing structures articulating between sealed and unsealed arrangements, one or both of the first and second lateral portions may be permanently or temporarily attached in a sealed arrangement to the wheel by a sealing structure.

[0069] Alternatively, it is also understood that a sealing junction may be created in particular embodiments by mechanically applying structure to forcibly form a sealing junction, such as by clipping or pinching the terminal ends together or in contact with another member, to close a vacuum chamber formed of at least the first and second portions. For example, first membrane portion 331 and second membrane portion 332 may be sealably connected to one another using a membrane portion connector (not pictured) which sealably clasps or connects first membrane portion 331 and second membrane portion 332. While first membrane portion 331 and second membrane portion 332 are shown as substantially symmetrical and connecting approximately half-way about the exterior bead-to-bead path, toward the middle of tread 323, it is understood that other configurations (e.g., asymmetrical arrangements) can be employed without departing from the scope or spirit of the innovation.

[0070] Wicking agent 314 can be provided between unbonded retreaded tire 320 and wheel 310. Wicking agent 314 creates one or more points of fluid communication between first vacuum chamber 351 and second vacuum chamber 352. In this way, vacuum interface 333 operates to remove air from both first vacuum chamber 351 and second vacuum chamber 352 while only being directly connected to one (e.g., via vacuum interface 333, depicted in the illustrated embodiment as connected to first vacuum chamber 351.

[0071] Membrane 330 is arranged about unbonded retreaded tire 320 such that first vacuum chamber 351 and second vacuum chamber 352 are sealed and capable of maintaining at least partial vacuum pressure. Membrane 330 includes first membrane portion 331 and second membrane portion 332.

[0072] First membrane portion 331 and second membrane portion 332 meet at junction 338. Such a junction may comprise a joint, an overlap, or a pleat, for example. It is understood that terminal edges of the degassing membrane include terminal edges of different portions of the membrane. A sealing junction may not be achieved until the one or more vacuum chambers are placed under vacuum or partial vacuum. It is also understood that a sealing junction may be achieved in particular embodiments by mechanically applying structure to forcibly form a sealing junction, such as by clipping or pinching the terminal ends together or in contact with another member, to close a vacuum chamber formed of at least the first and second portions. While first membrane portion 331 and second membrane portion 332 are shown as substantially symmetrical and connecting approximately half-way about the exterior bead-to-bead path, toward the middle of tread 323, it is understood that other configurations (e.g., asymmetrical arrangements) can be employed without departing from the scope or spirit of the innovation.

[0073] In some embodiments, tire-membrane assembly 300 can further include inflatable bladder 337. Inflatable bladder 337 can be disposed within unbonded retreaded tire 320, and specifically be on an inner cavity of tire carcass 321. Inflatable bladder 337 can be inflated and pressurized using pressure provided through pressure interface 311. Inflatable bladder 337 can fill at least a portion of the space within the tire, reducing the volume of second vacuum chamber 352. In embodiments, inflatable bladder 337 can prevent deformation of unbonded retreaded tire 320 potentially caused by at least partial vacuum pressure in second vacuum chamber 352, or otherwise assist with forming or supporting unbonded retreaded tire 320.

[0074] Tire-membrane assembly 300 can utilize vacuum source 354 and pressure source 356. Vacuum source 354 is connected to membrane 330 via vacuum hose 353, which couples with vacuum interface 333 to allow the removal of air from at least one of first vacuum chamber 351 and second vacuum chamber 352. Similarly, pressure source 356 is connected to inflatable bladder 337 using pressure hose 355, which couples with pressure interface 311. While these aspects are shown as single components, it is understood that two or more vacuum and/or pressure sources, and multiple vacuum and/or pressure interfaces can be utilized (e.g., two vacuum sources and two vacuum interfaces to separately apply at least partial vacuum pressure to first vacuum chamber 351 and second vacuum chamber 352 with or without wicking agents). Further vacuum source 354 and pressure source 356 can be utilized in other operations (e.g., pressure source 356 can pressurize a degassing or curing chamber) without departing from the scope or spirit of the innovation disclosed herein. [0075] In one or more specific embodiments, tire-membrane assembly 300 can include a single first vacuum chamber 351 but no other vacuum chambers. For example, inflatable bladder 337 can be inflated to fill all or substantially all of the inner cavity defined within carcass 321 (the open space defined within carcass 321 between unbonded retreaded tire 320 and wheel 310 when inflatable bladder 337 is uninflated). Some such embodiments may still employ one or both of first wicking agent 314 and second wicking agent 315 to eliminate or prevent the existence of second vacuum chamber 352 by permitting airflow through first vacuum chamber 351 such that inflatable bladder 337 fits tightly to carcass 321 and/or wheel 310. In alternative embodiments, vacuum chamber 351 is fluidly sealed from the inner cavity of carcass 321.

[0076] Fig. 4 particularly illustrates an operation chamber 400 showing tire- membrane assembly 300 mounted therein. As noted above, tire-membrane assembly 300 can be mounted on wheel support 360 for support in operation chamber 400. Operation chamber 400 can include chamber door 362 which can be opened, and in a closed position provides an airtight, pressure-resistant seal which isolates the inside of operation chamber 400 from an external environment. Operation chamber 400 can additionally include pressure source 364 which is coupled to one or more pressure and/or vacuum sources utilized to increase or decrease pressure in operation chamber 400.

[0077] Fig. 5 in particular shows a perspective view of the assembled degassing assembly 300. The view provided of degassing assembly 300 illustrates the contours of wheel 310 and unbonded retreaded tire 320 as covered by degassing membrane 330. At least sealing structures 340A and 340B are shown about degassing membrane 330.

[0078] As suggested throughout this disclosure, the present invention can include various controls, including automation, to effect processes or manage components of aspects herein. Fig. 6 illustrates a view of a controller 600 for use controlling or automating one or more aspects of the invention. Controller 600 includes user interface 602 which provides visualization and/or control surfaces to monitor or modify functioning of aspects herewith. For example, one or more of controlling a linear or annular continuous autoclave, opening or closing chambers or partitions, applying or removing a degassing membrane, increasing or reducing pressure in one or more chambers or bladders, changing a temperature in a sealed environment, monitoring time, conveying tires or other objects between locations, and initiating or ceasing various degassing or curing operations can be controlled via user interface 602 or other portions of controller 600.

[0079] Controller 600 generally receives signal responses from sensors related to degassing or curing chambers to monitor and help control the operation of systems or execution of methods herein. Controller 20 includes a logic processor 608, which may be a microprocessor, a memory storage device 606, such as RAM (random access memory), ROM (read-only memory), PROM (programmable read-only memory), and at least one input/output (I/O) cable 610 for communicating with systems described herein. Further, controller may include an I/O slot 612 for housing an I/O card having I/O cable connector 614.

[0080] An operator may utilize a user-interface 602 to monitor sensor measurements or the performance of systems and methods disclosed herein, and to program (or otherwise control or instruct), the operation of controller 600 and, for example, linear continuous autoclave 100 or annular continuous autoclave 200 (and/or associated components), which includes performing any portion of any method associated with degassing and/or curing as detailed herein. User-interface 602 and controller 600 may communicate by way of I/O cable 604. It is also contemplated that wireless communications may exist between controller 600, user-interface 602, and, for example, linear continuous autoclave 100 or annular continuous autoclave 200 (or other systems described herein).

[0081] Generally, controller 600 may be programmed by any known graphical or text language. Programmed instructions, data, input, and output may be stored in a memory storage device 606, which is accessible to processor 608. Memory device 606 may comprise any commercially known storage device, such as such as hard disk drives, optical storage devices, flash memory, and the like. Processor 608 executes programmed instructions and may perform the distance calculations and measurements, as wells as other operations, discussed herein. Memory storage device 606 also stores inputs, outputs, and other information, such as, for example, specifications or recipes for degassing or curing, for use by processor 608 in performing its operations. In addition to performing distance conversions and measurements, controller 600 may also be programmed to generate various instructions related to degassing or curing based upon received input. Using such aspects, degassing and/or curing operations may be automatically controlled based on stored recipes or routines or may be manually controlled by an operator or supervisor. Various combinations of automated and manual aspects related to systems and methods herein can be completed without departing from the scope or spirit of this disclosure.

[0082] The present invention may be utilized in association with retreaded tires, which may be utilized on particular types of vehicles or in specific applications. Nevertheless, the present invention may be utilized in association with any type of tire to form new or retreaded tire and as such, any type of tire may provide an embodiment of the present invention. Exemplary tire types for use with the subject invention further include light truck tires, heavy truck tires, off the road tires, bus tires, aircraft tires, bicycle tires, motorcycle tires, and passenger vehicle tires.

[0083] The terms "comprising," "including," and "having," as used in the claims and specification herein, shall be considered as indicating an open group that may include other elements not specified. The terms "a," "an," and the singular forms of words shall be taken to include the plural form of the same words, such that the terms mean that one or more of something is provided. The terms "at least one" and "one or more" are used interchangeably. The term "single" shall be used to indicate that one and only one of something is intended. Similarly, other specific integer values, such as "two," are used when a specific number of things is intended. The terms "preferably," "preferred," "prefer," "optionally," "may," and similar terms are used to indicate that an item, condition or step being referred to is an optional (i.e. , not required) feature of the invention. Ranges that are described as being "between a and b" are inclusive of the values for "a" and "b" unless otherwise specified.

[0084] While this invention has been described with reference to particular embodiments thereof, it shall be understood that such description is by way of illustration only and should not be construed as limiting the scope of the claimed invention. Accordingly, the scope and content of the invention are to be defined only by the terms of the following claims. Furthermore, it is understood that the features of any specific embodiment discussed herein may be combined with one or more features of any one or more embodiments otherwise discussed or contemplated herein unless otherwise stated. As used herein, the term process or method refers to one or more steps that may be performed in any order without departing from the scope of the invention. Also, some steps may be optional and may be omitted.

Claims

CLAIMS What is claimed is:

1. A method for curing tires, comprising:

providing a system for curing retreaded tires, the system including a series of chambers;

providing an unbonded retreaded tire, which comprises a pre-cured tread arranged annularly around an outer circumference of an annular tire carcass with a bonding layer comprising uncured bonding material arranged between the pre-cured tread and the annular tire carcass, the unbonded retreaded tire having a thickness extending between inner and outer sides of the unbonded retreaded tire, where the annular tire carcass comprises a pair of sidewalk spaced apart in an axial direction of the tire, each of the pair of sidewalk extending radially inward from an undertread portion to a bead portion;

placing the unbonded retreaded tire into an input chamber;

sealing the input chamber from an external environment using an input door;

conveying the unbonded retreaded tire from the input chamber;

sealing a curing chamber among the series of chambers;

pressurizing the curing chamber to a target curing pressure based at least in part on a curing operation for the unbonded retreaded tire;

heating the curing chamber to a target curing temperature based at least in part on a curing operation for the unbonded retreaded tire;

curing the unbonded retreaded tire in the curing chamber to complete the curing operation on the unbonded retreaded tire producing a cured tire;

unsealing the curing chamber to a removal chamber among the series of chambers; conveying the cured tire from the curing chamber to the removal chamber;

depressurizing the removal chamber based at least in part on an environmental pressure or an environmental temperature of the external environment;

unsealing the removal chamber from the external environment using a removal door; and

removing the cured tire from the removal chamber.

2. The method of claim 1, further comprising:

sealing a degassing chamber among the series of chambers; pressuring the degassing chamber to a target degassing pressure based at least in part on a degassing operation for the unbonded retreaded tire;

degassing the unbonded retreaded tire in the degassing chamber to complete the degassing operation on the unbonded retreaded tire;

unsealing the degassing chamber to the curing chamber; and

conveying the unbonded retreaded tire from the degassing chamber to the curing chamber.

3. The method of claim 2, where the degassing chamber is the input chamber.

4. The method of claim 2, further comprising pressurizing the input chamber based at least in part on the target degassing pressure.

5. The method of claim 1, where the curing chamber is the removal chamber.

6. The method of claim 1, where conveying is executed at high speed to limit a loss of at least one of pressure or heat between the series of chambers.

7. The method of claim 1, further comprising pressurizing at least one of the input chamber and the removal chamber based at least in part on the target curing pressure.

8. The method of claim 1, further comprising heating at least one of the input chamber and the removal chamber based at least in part on the target curing temperature.

9. The method of claim 1, further comprising:

providing a fluid communication connection between two or more chambers among the series of chambers; and

equalizing pressure between the two or more of the series of chambers before unsealing any of the two or more chambers.

10. The method of claim 1, where conveying the unbonded retreaded tire includes transporting the unbonded retreaded tire along a linear path.

11. The method of claim 1, where conveying the unbonded retreaded tire includes transporting the unbonded retreaded tire along an annular path.

12. A system for curing an unbonded retreaded tire, which comprises a pre-cured tread arranged annularly around an outer circumference of an annular tire carcass with a bonding layer comprising uncured bonding material arranged between the pre-cured tread and the annular tire carcass, the unbonded retreaded tire having a thickness extending between inner and outer sides of the unbonded retreaded tire, where the annular tire carcass comprises a pair of sidewalls spaced apart in an axial direction of the tire, each of the pair of sidewalls extending radially inward from an undertread portion to a bead portion, comprising:

a series of chambers, the series of chambers being interconnected and sealed from an external environment when an input door and a removal door are closed;

a conveyor component that conveys the unbonded retreaded tire between two or more of the series of chambers;

a sealable input chamber of the series of chambers having the input door;

a sealable curing chamber of the series of chambers that performs a curing operation on the unbonded retreaded tire;

a pressure source that pressurizes at least the curing chamber to one or more target curing pressures based at least in part on the unbonded retreaded tire in accordance with the curing operation;

a heating element that heats at least the curing chamber to one or more target curing temperatures based at least in part on the unbonded retreaded tire in accordance with the curing operation;

a sealable removal chamber of the series of chambers having the removal door; and a plurality of inter-chamber interfaces to effect sealing of at least the input chamber, the curing chamber, and the removal chamber from another chamber among the series of chambers.

13. The system of claim 12, further comprising a sealable degassing chamber of the series of chambers that performs at least one degassing operation on the unbonded retreaded tire, where the sealable degassing chamber shares at least a first interface of the plurality of inter- chamber interfaces with the input chamber and at least a second interface of the plurality of inter-chamber interfaces with the curing chamber.

14. The system of claim 13, where the degassing chamber is volumetrically smaller than the curing chamber.

15. The system of claim 13, further comprising a degassing assembly component that assembles or disassembles a degassing assembly including at least the unbonded retreaded tire and a degassing membrane.

16. The system of claim 12, where at least one of the input chamber and the removal chamber is volumetrically smaller than the curing chamber.

17. The system of claim 12, further comprising a fluid communication connection between two or more of the series of chambers, the fluid communication connection includes a control to effect and prevent fluid communication between the two or more chambers.

18. The system of claim 12, where the series of chambers define a continuous linear path isolated from the external environment.

19. The system of claim 12, where the series of chambers define a continuous annular path isolated from the external environment.

20. The system of claim 12, further comprising a control system that controls at least one of a pressure within the series of chambers, a temperature within the series of chambers and a speed of the conveyor component.