JP2014133383A - Unvulcanized base tire and base tire, and tire and method of producing tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a suitable unvulcanized base tire and base tire that have high quality and make uniform a vulcanization degree in the production of the new tire and are less likely to cause uneven wear in using the tire in re-treading of the worn away new tire so as to be reusable as the tire again when the new tire is worn away, and to provide a method of producing a tire for producing a new tire using the base tire.SOLUTION: A cross-section thickness D3 in a side area A3, a cross-section thickness D2 in a buttress area A2 and a cross-section thickness D1 in a tread area A1 of an unvulcanized base tire are set to be a substantially equal thickness and vulcanization is performed.

Description

  TECHNICAL FIELD The present invention relates to an unvulcanized table tire and a table tire, and a tire and a tire manufacturing method, and more particularly, an unvulcanized table tire to which a tread is stuck in a subsequent process, a table tire formed by vulcanizing the tire, and the table. The present invention relates to a tire manufacturing method using a tire.

Conventionally, a new product tire has a tire component such as an unvulcanized rubber member laminated together, vulcanized an unvulcanized base tire formed by assembling, a base tire is formed, and a tread is integrated on the surface side thereof. What is formed as a new tire is well known.
However, since the thickness of the new tire manufactured by the above method varies depending on the tread region, buttress region, side region, bead region, and the like (see Patent Document 1, etc.), Since the vulcanization is based on the thickness of the thickest buttress area, the vulcanization of the buttress area is completed even though the other parts that are thinner than the buttress area have already been vulcanized. Vulcanization will be continued until this occurs, and the degree of vulcanization tends to be uneven in new tires and base tires after vulcanization. New tires manufactured with non-uniformity in the degree of vulcanization in this way may have reduced uniformity in the tire, increasing rolling resistance during actual use or causing uneven wear. There is. In order to prevent unevenness of the vulcanization degree in this tire, in Patent Document 2, a large amount of heat is given to a thick part, and a heat amount smaller than that of a thick part is given to a thin part. Although a tire manufacturing method that makes the degree of vulcanization uniform is disclosed, it is necessary to adjust the amount of heat given to each tire type in order to vulcanize the tire with a uniform degree of vulcanization. , The time required for vulcanization becomes longer.
Further, in recent years, tires manufactured by the above-described method have a worn tread removed from a used tire when a use limit is reached, as shown in Patent Document 3, and a new tread is pasted. The retread can be used again as a tire, but when the tread is cut to obtain a base tire, if this base tire has a decrease in uniformity, the tread is attached to the base tire. When the tire was re-treaded and completed as a tire, there was a risk that the effect of the above-mentioned uniformity decrease appeared again as uneven wear when the vehicle was running.

Japanese Patent Laid-Open No. 10-193472 JP 2006-035615 A JP 2000-79641 A

  Therefore, the problem to be solved by the present invention is that the degree of vulcanization at the time of manufacturing a new tire is made uniform, and when this new tire is worn, it is unevenly worn for tire use in the retread that can be reused as a tire again. An object of the present invention is to provide a high quality suitable unvulcanized table tire and table tire excellent in uniformity, and a tire and tire manufacturing method.

As an aspect of the unvulcanized table tire for solving the above-mentioned problem, the cross-sectional thickness D3 in the side region A3, the cross-sectional thickness D2 in the buttress region A2, and the cross-sectional thickness D1 in the tread region A1 are set to substantially equal thicknesses. As a result, the degree of vulcanization of the base tire can be made constant. As a result, the base tire has uniform hardness throughout the base tire and is excellent in uniformity, and when used as a base for manufacturing a new tire, uneven wear with excellent rolling resistance occurs. It becomes possible to provide a difficult new tire. In addition, when a new tire manufactured based on the above base tire reaches the limit of use and becomes a used tire, the worn tread is removed and a new new tread is pasted and used again as a tire. Even when retreading is possible, it is suitable as a base, and the retreaded tire is also excellent in uniformity. Furthermore, since the cross-sectional thicknesses in the side region A3, buttress region A2, and tread region A1 are substantially equal, the temperature and vulcanization time during vulcanization of the unvulcanized stand tire can be easily managed, and the production efficiency during vulcanization is improved. Can be improved.
Further, as another aspect of the unvulcanized table tire for solving the above-mentioned problem, the buttress area A2 and the tread area A1 from the position of the maximum width portions 20A and 20A positioned on the outer surface of the side area A3 in the width direction. By setting the cross-sectional thickness in the range ZA to be substantially equal, the degree of vulcanization in the range ZA can be made uniform, and a base tire that is less prone to uneven wear can be obtained in the range ZA as described above. In addition, the range ZA, which is the setting management area for the cross-sectional thickness, can be set to be smaller than the above-described areas A1 to A4 of the entire base tire. As a result, the vulcanization temperature can be set within the minimum necessary range, and even if it is set in this way, the portion that is most likely to be worn during running is within the range ZA, which causes a problem when used as a tire. Absent. In addition, the vulcanization temperature can be easily managed by partially setting the thickness in this way.
Further, as another aspect of the unvulcanized stand tire for solving the above-described problem, the rising portions 20D and 20D on the tread region A1 side of the protruding portion 25 protruding to the outer surface of the boundary portion between the side region A3 and the bead region A4. By setting the cross-sectional thickness in the range ZB of the side region A3, buttress region A2, and tread region A1 from the position of the vulcanized region, vulcanization in the range of the buttress region A2 and tread region A1 from the position of the rising portions 20D and 20D. The degree can be made uniform. Accordingly, in addition to the above effects, the positions of the rising portions 20D and 20D can be easily specified, so that the vulcanization range can be easily set.
Moreover, as an aspect of the base tire for solving the above-mentioned problems, the unvulcanized base tire according to any one of claims 1 to 3 can be heated at a uniform temperature over the tread region A1, the buttress region A2, and the side region A3. The vulcanization degree of the tread area A1, buttress area A2, and side area A3 can be made uniform. As a result, the hardness in the tread area A1, buttress area A2 and side area A3 of the base tire is uniform and excellent in uniformity, and rolling resistance when used as a base when manufacturing a new tire. It is possible to provide a tire that is superior in uneven wear and that is less susceptible to uneven wear.
As another aspect of the pedestal tire for solving the above-described problems, when the unvulcanized pedestal tire according to any one of claims 1 to 3 is vulcanized, the uneven portion 29 is within the range of the buttress area A2. Was formed. Accordingly, when the unvulcanized table tire is vulcanized and molded, the members constituting the tread region A1, buttress region A2, and side region A3 of the unvulcanized table tire flow in the radial direction and the width direction with unevenness. It can prevent and it can prevent that cross-sectional thickness of tread area | region A1, buttress area | region A2, and side area | region A3 of the base tire after vulcanization becomes non-uniform | heterogenous.
Further, as an aspect of the tire for solving the above-described problem, the tread 3 is attached to the outer surface of the tread region A1 and the buttress region A2 of the base tire according to claim 4 or 5, so that the buttress is removed from the tread region A1. A tire in which the degree of vulcanization through the region A2 to the side region A3 is made uniform can be configured.
Further, as an aspect of a tire manufacturing method for solving the above-described problem, the tread 3 is placed on the outer surface of the tread region A1 and the buttress region A2 of the base tire according to claim 4 or 5 via a cushion rubber 4. By vulcanizing and attaching the tread 3 to the base tire 1 with the cushion rubber 4, a tire having a uniform degree of vulcanization from the tread area A1 to the side area A3 through the buttress area A2 can be manufactured. .

It is a schematic structure sectional view of a base tire. It is sectional drawing of a vulcanizer. It is a lineblock diagram of a tire. It is sectional drawing which shows the other form of a base tire. It is sectional drawing which shows the other form of a base tire. It is sectional drawing which shows the other form of a base tire. It is sectional drawing which shows the other form of the buttress part in a base tire.

  FIG. 1 is a cross-sectional view showing an embodiment of an unvulcanized table tire and a vulcanizing method according to an embodiment of the present invention. Since the shape of the unvulcanized table tire is generally different from the shape of the product tire, in order to facilitate the explanation, in the same figure, the tire shape is illustrated with a tire shape close to the product shape. In FIG. 1, reference numeral 1 denotes a base tire in which a tread is attached to the attaching surface in a subsequent process, and a ring-shaped bead core 11 in which steel cords called bead cords forming a skeleton are bundled. The reinforcing cord is formed by laminating a plurality of carcass 12 oriented so as to form a toroidal shape in the radial direction of the tire (radial direction) and a sheet-like belt oriented such that the reinforcing cord is inclined with respect to the circumferential direction. The belt layer 13 is provided. Although the figure of the bead mooring form which winds up a bead core with a carcass is shown in the same figure, the form which pinches | interposes a carcass inside a bead core may be sufficient.

  The base tire 1 is an unvulcanized so-called raw base tire, and includes a bead filler 15, an inner liner 16, side rubber 17, and a base tread 18 mainly composed of a plurality of types of rubber members for fleshing a skeleton made of the cord member or the like. . Specifically, a bead filler 15 that reinforces the bead region A4, an inner liner 16 that covers the inner peripheral surface of the carcass 12, a side rubber 17 that covers the carcass 12 on the side surface of the base tire 1 from the outside, and left and right side rubbers 17 A table tread 18 is provided between the belt layer 13 and the belt tread 18. Hereinafter, the bead filler 15, the inner liner 16, the side rubber 17, and the base tread 18 may be collectively referred to as a rubber member.

In FIG. 1, A1 is a tread region corresponding to the road contact side, A2 is a buttress region that is a shoulder portion of a base tire, A3 is a side region, A4 is a bead region that is an assembly portion with a wheel rim, and Ba is a base tire inner diameter. The edge part and R are tread sticking area | regions.
D1 is a cross-sectional thickness (gauge) in the tread region A1, D2 is a cross-sectional thickness in the buttress region A2, D3 is a cross-sectional thickness in the side region A3, and D4 is a cross-sectional thickness in the bead region A4. D1 to D4 are thickness dimensions when a normal line perpendicular to the inner surface side of the base tire when air is not filled is taken. The important point in this example is that D1≈D2≈D3, and the sectional thickness (gauge) of the range Z including the tread region A1, buttress region A2, side region A3 of the base tire is substantially equal. To do. In addition, that cross-sectional thickness (gauge) is substantially equal means that it is substantially the same thickness. That is, the cross-sectional thickness D2 of the buttress area A2 is set to be the same as the cross-sectional thickness D1 and the cross-sectional thickness D3. In this case, the tread region A1, the buttress region A2, and the side region A3 set with the cross-sectional thicknesses D1, D2, and D3 having substantially the same values are temperatures that do not cause over-vulcanization and insufficient vulcanization during vulcanization described later. Set to The cross-sectional thickness D4 has a bead core 11 and is thicker than the cross-sectional thicknesses D1 to D3 in order to fit the wheel rim portion.
In addition, the cross-sectional thickness D3 can be thin or thick within a certain allowable range in the direction of the bead filler 15 while satisfying the above relationship.

Raw stand tire assembly step The above base tire 1 is assembled as a raw stand tire before vulcanization molding, for example, as follows.
First, an unvulcanized sheet-shaped inner liner 16 is wound around a cylindrical forming drum along the circumferential direction of the forming drum, and then an unvulcanized sheet formed into a sheet shape on the outer periphery of the inner liner 16. The carcass 12 of sulfur is wound and laminated.

  Next, the bead core 11 and the unvulcanized bead filler 15 formed in a ring shape in advance are fitted on the outer circumferences on both ends of the carcass 12 from both ends of the forming drum so as to surround the bead core 11 and the bead filler 15. The end of the carcass 12 is folded and wound up.

  Next, the side rubber 17 formed in a belt shape is wound around the carcass 12 and laminated at positions corresponding to the left and right side regions A3; A3, that is, the side surfaces of the base tire 1 after vulcanization. The bulging means incorporated in the molding drum is operated to bulge the center in the width direction of the laminated member group in the radial direction so as to form a toroidal shape. The belt layer 13 is formed by winding and laminating a plurality of unvulcanized belts.

  Next, the outer periphery of the belt layer 13 positioned radially outermost so that the unvulcanized table tread 18 formed in a band shape wider than the width of the belt layer 13 overlaps the inner end of the side rubber 17. Wind and laminate on the surface. The pedestal tread 18 becomes a tread region A1 in the pedestal tire 1 after vulcanization molding, and becomes a part of the tread adhesion region R in a later process. The green tire is molded on the molding drum by the above process.

  The table tread 18 in the tread region A1 is connected to the end portion 14A of the widest belt 14 of the belt layer 13 on the outer side with a cross-sectional thickness H1 in a range V1 overlapping with the belt layer 13 in which a plurality of belts are laminated. It is set to be thinner than the cross-sectional thickness H2, and the cross-sectional thickness H3 in the range V2 overlapping with the side rubber 17 is set to gradually become thinner from the inner side in the tire width direction toward the outer side. That is, the inner side of both ends of the table tread 18 is inclined and set to be gradually thinner. The cross-sectional thickness D1 in the tread region A1 is the sum of the cross-sectional thickness H1 of the table tread 18 in the range V1 overlapping with the belt layer 13, the thickness of the belt layer 13, and the thickness of the inner liner 16.

  The side rubber 17 in the side region A3 is vulcanized from the position where the overlap with the table tread 18 is completed by gradually increasing the cross-sectional thickness H4 from the end overlapping the table tread 18 in the range V2 overlapping the table tread 18. The cross-sectional thickness H5 is set to be uniform up to the position of the maximum width portion 20A in the rear tire 1, and the cross-sectional thickness is constant over the bead maximum thickness portion Bmax which is the maximum thickness portion in the bead region A4. Set. That is, the outer side of the end portion of the side rubber 17 on the side of the table tread 18 is inclined so as to be gradually thickened.

In this way, the cross-sectional thicknesses of the table tread 18 and the side rubber 17 are set in advance, and the inclination on the end side of the table tread 18 and the inclination on the end side of the side rubber 17 are overlapped. By maintaining the cross-sectional thickness, the outer surface of the vulcanizer is expanded from the inner surface to the mold by inflating the bladder of the vulcanizer during the vulcanization molding due to the friction of the overlapping part. It is possible to vulcanize and mold the base tire 1 as shown in FIG. 1 without causing the tire tread 18 and the side rubber 17 occupying most of the tire to flow in the radial direction of the tire.
That is, the green tires assembled and molded as described above are in an unvulcanized state, and at this time, a tread 3 described later is not disposed in the tread region A1.

  The side rubber 17 and the table tread 18 described above are preferably made of rubber materials having different rubber characteristics. In particular, by using rubber materials having different characteristics for the side rubber 17 and the base tread 18 constituting the side region A3, the performance of each part of the base tire 1 after vulcanization can be specialized. .

  For example, a rubber material having excellent cut resistance is used for the side rubber 17, and a rubber material having a high vulcanization adhesive property with the tread 3 is used for the base tread 18, so that each part in the base tire 1 is used. Can be specialized in performance. Further, by applying a rubber material having a high rigidity characteristic to improve the maneuverability and a rubber material having a low rigidity characteristic to improve the riding comfort to the side rubber 17 and the base tread 18, a base tire is obtained. The performance as 1 can be further specialized.

  Note that it is not always necessary to use rubber materials having different characteristics in the above members, and rubber materials having the same characteristics may be used for the table tread 18 and the side rubber 17. By using the same rubber material for the table tread 18 and the side rubber 17, it is not necessary to replace the rubber material when the table tread 18 and the side rubber 17 are molded as members, thereby reducing the number of steps for molding the rubber member. It is also possible. That is, the base tire 1 may be configured by appropriately selecting the rubber members used for the side rubber 17 and the base tread 18 from the rubber characteristics according to the specifications of the base tire 1.

  The green tire is vulcanized by a vulcanizing device 30 described later in a state where no tread rubber serving as a tire contact portion is disposed, and after forming an adhesive layer on the table tread 18, The tread 3 having been subjected to sulfur molding is disposed on the outer periphery of the adhesive layer, and the adhesive layer is vulcanized to be integrated. The details of the tire manufacturing method will be described later.

Next, a vulcanizing apparatus 30 for suitably vulcanizing and molding the green tire described above will be described with reference to FIG.
In FIG. 2, the vulcanizing device 30 mainly includes a lower platen 31, a lower mold 32, a lower bead mold 33, an upper platen 34, an upper mold 35, an upper bead mold 36, a bladder 37, and the like.
The lower platen 31 is an annular plate, and has a flow path 31A through which a heating medium such as high-temperature and high-pressure steam or liquid is supplied from a heat source supply device (not shown). The channel 31A is an annular space formed at a position corresponding to the lower side region A3 of the green tire, and mainly heats the lower side region A3 via the lower mold 32 positioned above. It functions as a flow path through which a heating medium that is a heat source that circulates. A lower mold 32 is fixed to the upper surface side of the lower platen 31. The lower mold 32 is an annular metal body made of, for example, aluminum and having an L-shaped cross section, and transfers heat from the lower platen 31 positioned below to the green tire.

  The lower mold 32 includes a side die attaching portion 32A in which an inner peripheral surface facing the lower side region A3 of the green tire is formed as a molding surface, and an inner peripheral surface facing the buttress region A2 of the green tire. It has a buttress die attaching portion 32B formed as a shaping surface and a tread die attaching portion 32C formed with an inner peripheral surface facing the tread region A1 which is a crown portion of the green tire as a shaping surface.

The mold surface of the side mold portion 32A is formed as a surface curved in the radial direction so as to surround the lower side region A3 of the green tire.
The molding surface of the buttress mold attachment portion 32B is curved in a radial direction so as to surround the buttress region A2 on the lower side of the green tire continuously with the molding surface of the side mold attachment portion 32A that molds the side region A3. It is formed as a surface that rises substantially perpendicular to the direction.
The molding surface of the tread mold portion 32C is a surface that rises substantially perpendicular to the width direction of the green tire continuously from the molding surface of the buttress mold mounting portion 32B that molds the buttress region A2, and extends from the buttress region A2 to the tread region. It is a surface which molds to the equator part 21 of A1.

  A detachable lower bead mold 33 is attached to the upper surface of the lower mold 32. The lower bead mold 33 is an annular body that molds the lower bead region A4 of the green tire and holds a later-described bladder 37 via the gripping portion 33A.

Similar to the lower platen 31, the upper platen 34 is an annular plate. The upper platen 34 is spaced apart from the lower platen 31 in the vertical direction, and is arranged in parallel to form a pair with the lower platen 31. The upper platen 34 can be moved up and down by a lifting mechanism (not shown).
Inside the upper platen 34, similarly to the lower platen 31, a flow path 34 </ b> A is provided in which a high-temperature and high-pressure heating medium is supplied from a heat source supply device (not shown) during vulcanization.

  The flow path 34A is an annular space formed at a position corresponding to the upper side region A3 and the buttress region A2 of the green tire, and the upper green tire is mainly interposed via the upper mold 35 positioned below. It functions as a flow path through which a heating medium that is a heat source for heating the liquid flows.

  The upper platen 34 is connected to a lifting mechanism (not shown). The elevating mechanism is attached to, for example, a cylinder that can be expanded and contracted in the vertical direction, and the upper platen 34 and the upper mold 35 fixed to the upper platen 34 are integrally moved up and down by the expansion and contraction operation of the cylinder, and are positioned below. The lower mold 32 is closed or opened.

  An upper mold 35 is fixed to the lower surface of the upper platen 34. The upper mold 35 is an annular metal body having an L-shaped cross section that forms a pair with the lower mold 32, and transfers heat from the upper platen 34 as a heat source located above to the green tire.

  The upper die 35 includes a side die attaching portion 35A in which an inner peripheral surface facing the upper side region A3 of the green tire is formed as a molding surface, and an inner peripheral surface facing the buttress region A2 on the upper side of the green tire. Has a buttress die attaching portion 35B formed as a shaping surface, and a tread die attaching portion 35C in which an inner peripheral surface facing the tread region A1 which is a crown portion of the green tire is formed as a shaping surface.

The molding surface of the side mold portion 35A is formed as a surface curved in the radial direction so as to surround the side region A3 on the upper side of the green tire.
The molding surface of the buttress mold part 35B is curved in a radial direction so as to surround the buttress area A2 on the upper side of the green tire continuously with the molding surface of the side mold part 32A that molds the upper side area A3. It is formed as a surface that rises substantially perpendicular to the width direction.
The molding surface of the tread attaching part 35C is a surface that hangs substantially perpendicular to the width direction of the green tire continuously from the attaching surface of the buttress attaching part 35B that molds the buttress area A2, and is tread from the buttress area A2. This is a surface for molding up to the equator portion 21 in the region A1.

  That is, the molding surfaces of the lower mold 32 and the upper mold 35 are designed exclusively for molding the tread adhesion region R of the base tire 1 according to the present invention into a predetermined shape, and are vulcanized. Designed according to the expanded shape of the bladder 37 during vulcanization molding so that the cross-sectional thicknesses D1, D2, D3 of the tread area A1, buttress area A2, and side area A3 of the base tire 1 after molding are substantially equal. ing.

  The upper die 35 includes an upper bead die 36 on the radially inner side with respect to the side die attaching portion 35A. The upper bead mold 36 is an annular body that molds the bead region A4 in the side region A3 on the upper side of the green tire and holds a later-described bladder 37 via the gripping portion 36A.

  The bladder 37 held by the lower bead mold 33 and the upper bead mold 36 is an extensible bag-like rubber body, and is disposed on the inner surface side of the green tire and supplied from a heat source supply device (not shown). The heating medium heated and pressurized to a predetermined temperature and a predetermined pressure is supplied to the inside and expands and adheres along the inner surface of the green tire.

  The green tire disposed in the space formed by the lower mold 32 and the lower bead mold 33, the upper mold 35 and the upper bead mold 36 is moved along with the expansion of the bladder 37 during vulcanization. The lower mold heated by the heating medium flowing through the flow path 34A of the upper platen 34 and the flow path 31A of the lower platen 31 while being pressed against the lower bead mold 33, the upper mold 35, and the upper bead mold 36. 32 and the lower bead mold 33, the upper mold 35 and the upper bead mold 36 are vulcanized by heating from the outer surface side, and the bladder 37 which is expanded by supplying a heating medium is heated from the inner surface side. Is done. Then, after the predetermined time has elapsed, the lower mold 32 and the lower bead mold 33, the upper mold 35 and the upper bead mold 36 are opened, and the vulcanized base tire 1 is obtained by removing the mold.

  The base tire 1 vulcanized and molded by the vulcanizer 30 is vulcanized into the shape shown in FIG. Specifically, the base tire 1 is vulcanized and molded so that the cross-sectional thicknesses D1, D2, and D3 of the tread region A1, buttress region A2, and the side region A3 are substantially equal, whereby the tread region A1, buttress region A2 and the side region A3 have almost the same vulcanization degree. That is, the cross-sectional thicknesses D1, D2, and D3 in the range Z of one side region A3 and buttress region A2, tread region A1, and the other side region A3 and buttress region A2 are substantially constant, and the degree of vulcanization is substantially uniform. And uniformly vulcanized. In this case, it is preferable to vulcanize so that the slowest part during vulcanization of the base tire 1 is the bead region A4.

Further, the base tire 1 is vulcanized so that the cross-sectional thickness gradually increases from the side regions A3, A3 to the bead thickest portion Bmax, and the cross-sectional thickness in the bead region A4 becomes the maximum thickness at the bead thickest portion Bmax. Molded. In addition, since the base tire 1 is composed of a rubber member, that the cross-sectional thickness is equal means a range that is considered to be substantially uniform, and has a predetermined allowable range.
Thus, by setting the cross-sectional thicknesses D1, D2, and D3 of the tread region A1, buttress region A2, and side region A3 of the base tire 1 to be substantially equal, the degree of vulcanization of the whole base tire is uniform. It can be.

  That is, at the time of molding the unvulcanized stand tire, the cross-sectional thicknesses of the left and right side regions A3; A3 and buttress regions A2; By performing vulcanization molding as it is, the degree of vulcanization of the left and right side regions A3; A3 and buttress regions A2; A2, and the tread region A1 can be made substantially uniform.

  Vulcanization by the vulcanization molding is performed with reference to the respective cross-sectional thicknesses D1, D2, and D3. In the base tire 1, the bead maximum thickness Bmax of the bead region A4 is the thickest of the base tires 1, and thus becomes the slowest part in the progress of vulcanization of the entire base tire. Since the bead core 11 made of the cord is embedded, the amount of heat heated at the time of vulcanization molding is stored in the bead core 11, so that the vulcanization of the bead region A4 is advanced even after demolding from the vulcanizer 30. Become. That is, the cross-sectional thickness is thinner than the bead area A4, and even if vulcanization molding is performed based on the cross-sectional thickness from the uniformly designed tread area A1 to the buttress area A2 to the side area A3, the table is finally obtained. The degree of vulcanization of the tire 1 can be made substantially uniform as a whole. Further, since the cross-sectional thicknesses in the side area A3, buttress area A2, and tread area A1 are substantially equal, the temperature and vulcanization time during vulcanization of the unvulcanized table tire can be easily managed, and the production efficiency during vulcanization can be achieved. Can be improved.

Tread Winding Step FIG. 3 is a structural view of a tire manufactured using the tyred tire 1 vulcanized as shown in FIGS.
The cushion rubber 4 is applied to the tread adhering region R including the ground contact portion tm corresponding to the tread region A1 of the tire 1 vulcanized by the above-described method and the fin portion tn corresponding to the buttress region A2 extending to the left and right ends thereof. A new tire as a product is manufactured by sticking a vulcanized tread 3 vulcanized in advance. Hereinafter, a tire manufacturing method will be described.
The tread 3 attached to the base tire 1 is vulcanized and molded in advance in a band shape or an annular shape having a predetermined length. For example, when the tread 3 has a belt shape, the tread surface 3 </ b> A on which the uneven tread pattern is formed and the attaching surface 3 </ b> B to be attached to the base tire 1 are formed. Further, in the case of an annular (cylindrical) tread 3, a tread surface 3 </ b> A on which a tread pattern is molded and a bonding surface 3 </ b> B to be bonded to the base tire 1 are molded.

  Such a tread 3 is set so that the cross-sectional thickness in the range of the ground contact portion tm on the tread surface 3A is substantially uniform. In addition, the fin part tn extended from the both right and left ends of the grounding part tm is set so that the cross-sectional thickness gradually decreases toward the tip. In this way, by setting the cross-sectional thickness of the tread 3, it is possible to perform vulcanization molding so that the degree of vulcanization of the tread 3 is uniform. Since the contact portion tm in the tread 3 is a friction surface with the road surface, particularly when there is a difference in the vulcanization degree in the width direction of the tread 3, the wear is caused between the high vulcanization part and the low vulcanization part. However, the uniformity tends to decrease and cause uneven wear. Therefore, by designing the cross-sectional thickness of the tread 3 in a range to be the ground contact portion tm so that the degree of vulcanization of the tread 3 is uniform, the tread 3 can be configured in which uneven wear hardly occurs. it can.

  The surface of the tread attaching region R of the base tire 1 to which the tread rubber 3 is attached is formed into a predetermined shape by a process called buffing. The predetermined shape means, for example, that the tread surface 3A of the tread 3 has a predetermined radius of curvature in the width direction when the tread 3 vulcanized and molded as described above is integrated with the tread attachment region R of the base tire 1. The shape set to have.

A vulcanized tread is formed by winding an unvulcanized sheet-like or belt-like cushion rubber 4 around the buffed tread adhering region R of the base tire 1 with a uniform thickness along the tire circumferential direction. An adhesive layer between the tire 3 and the base tire 1 is formed. A tread 3 is disposed on the cushion rubber 4. The formation of the adhesive layer is not limited to the unvulcanized sheet-like or belt-like cushion rubber 4, and liquid rubber or the like may be used.
The base tire 1 in which the tread 3 is disposed has a bead ring in which the outer surfaces of the base tire 1 and the tread 3 are covered by a cover called an envelope (not shown), and the cover is in close contact with the edge Ba of the base tire inner diameter. The outer surface of the base tire 1 and the tread 3 is hermetically sealed with an envelope.

Next, the base tire 1 and the tread 3 covered with the envelope are put into a vulcanizing container called an autoclave. The vulcanization container is a facility in which the pressure and temperature in the container can be adjusted, and is disposed between the base tire 1 and the tread 3 covered with the envelope while adjusting the pressure and temperature in the container. The cushion rubber 4 is vulcanized, and the base tire 1 and the tread 3 are fixed together. Then, after a predetermined time has elapsed, the base tire 1 and the tread 3 covered with the envelope are taken out from the vulcanization container, and the envelope is removed to produce a new product tire in which the tread 3 is integrally fixed to the base tire 1. Is done. In addition, although the said tread 3 demonstrated as having used the vulcanized thing, you may obtain the adhesive force by vulcanizing with the said vulcanization container using an unvulcanized thing.

  As described above, when the base tire 1 is vulcanized and molded alone, a high-quality base tire 1 can be obtained even by re-vulcanization with the vulcanizing container by adding the condition that the cross-sectional thickness D1≈D2≈D3. When the base tire 1 and the tread 3 that are individually vulcanized and molded are integrally manufactured using the base tire 1 as in this embodiment, the entire tire is vulcanized. The degree is almost uniform.

  The base tire 1 vulcanized and molded as described above has high-quality performance as a base for the tire, and when the product tire is integrated with the tread 3, or when this product tire reaches the use limit. When retreading (cutting the worn tread and sticking a new vulcanized tread to the cut part to make it a reusable tire), it can be reused repeatedly as a base tire while maintaining excellent performance. can do.

Other Embodiments As shown in FIG. 4, the base tire 1 normally has side rubber 17 bulging outward in the width direction on the road surface ground side (base tread side). In this case, the cross-sectional thicknesses in the range ZA of the buttress area A2 and the tread area A1 are set to be approximately equal from the position of the maximum width portions 20A and 20A positioned on the outer surface of the side area A3 in the width direction. That is, the relationship between the cross-sectional thickness D3 of the maximum width portions 20A and 20A, the cross-sectional thickness D2 of the buttress region A2, and the cross-sectional thickness D1 of the tread region A1 is expressed by the cross-sectional thickness D1≈the cross-sectional thickness D2≈the cross-sectional thickness. Let D3. This has the effect of preventing uneven wear in the range ZA in the same manner as described above, and can set the sectional thickness setting management region ZA to be smaller than the range Z described above. As a result, the vulcanization temperature can be set within the minimum necessary range, and even if it is set in this way, the portion that is most likely to be worn during running is within the range ZA, which causes a problem when used as a tire. Absent. In addition, the vulcanization temperature can be easily managed by partially setting the thickness in this way. In this case, the cross-sectional thickness from the maximum width portions 20A and 20A to the bead regions A4 and A4 may be set with a necessary degree of freedom within an allowable range.

Other Embodiments As shown in FIG. 5, when the base tire 100 has a protruding portion 25 at a substantially boundary portion between the side region A3 and the bead region A4, that is, a rim guard that protects the wheel rim on the tire side surface. In the case of providing, the cross-sectional thicknesses in the range ZB of the buttress area A2 and the tread area A1 from the positions of the rising parts 20D and 20D on the tread A1 side of the protrusion 25 are substantially the same. The maximum width portion 20C is the tip of the protruding portion 25. This makes it possible to set the sectional thickness setting management region to a small width. As a result, the vulcanization temperature can be set within the minimum necessary range, and the vulcanization temperature can be easily managed. In this case, the cross-sectional thickness from the maximum width portions 20A and 20A to the bead regions A4 and A4 may be set with a necessary degree of freedom within an allowable range. Further, since the positions of the maximum width portions 20C and 20C are portions where the lower end of the side region A3 protrudes, it is easy to specify the rising portions 20D and 20D adjacent to the maximum width portion 20C and set the vulcanization range. Becomes easy.

Other Embodiments As described above with reference to FIG. 1, the base tire 200 is basically set at the cross-sectional thickness D1≈the cross-sectional thickness D2≈the cross-sectional thickness D3. As shown in FIG. 6, uneven portions 29, 29 may be formed on the outer surface side of the buttress area A <b> 2. As a result, when the unvulcanized table tire is vulcanized and molded, the members constituting the tread region A1, buttress region A2, and side region A3 of the unvulcanized table tire flow in the radial direction and the width direction. It is possible to prevent unevenness of the cross-sectional thicknesses of the tread region A1, buttress region A2, and side region A3 of the vulcanized base tire by blocking with the unevenness of 29 and 29. In addition, the depth of the unevenness of the uneven portion 29 is set within an allowable range such that the cross-sectional thickness at each position can be vulcanized without excess or deficiency.
By forming the concavo-convex portion 29 in the buttress area A2 in this way, the rubber of the tread rubber and the side rubber 17 is melted during vulcanization molding, and a part of the tread rubber and the side rubber 17 flows downward (in the direction of the side area A3). By preventing the tread rubber and the side rubber 17 from drooping to the side region A3 side, and the cross-sectional thicknesses of the tread region A1, buttress region A2, and side region A3 after vulcanization molding are approximately D1≈D2≈D3. Can be easily set. Therefore, a high-quality tire can be configured by using this base tire as a base for manufacturing the tire.

Other Embodiments The cross-sectional thicknesses of the tread region A1, buttress region A2, and side region A3 having the cross-sectional thickness D1 are basically the buttress while maintaining the cross-sectional thickness D1≈the cross-sectional thickness D2≈the cross-sectional thickness D3. In the region, as shown in FIG. 7A, the cross-sectional thickness D2 (≈cross-sectional thickness D1≈cross-sectional thickness D3) or the cross-sectional thickness D3 (≈cross-sectional thickness D1≈cross-sectional thickness D2). On the other hand, only Dα may be thick, or as shown in FIG. 7B, Dβ may be thin relative to the cross-sectional thickness D2. In this case, the maximum allowable limit of Dα is the cross-sectional thickness D2 (≈cross-sectional thickness D1≈cross-sectional thickness D3) or the cross-sectional thickness D3 (≈cross-sectional thickness D1≈cross-sectional thickness D2). If the cross-sectional thickness D1 is set to 30% and the minimum allowable limit of Dβ is set to 30% of the cross-sectional thickness D1, no inconvenience occurs in uniformizing the vulcanization of the base tire 1. Thus, by increasing or decreasing the cross-sectional thicknesses D2 and D3 within an allowable range as necessary, the tolerance in tire design can be improved and a high-quality tire can be manufactured.

In the above description, the structure of the base tire 1 has been described using the basic structure of a tire for a passenger car, but the members and the structure constituting the base tire 1 are not limited to the above.
Further, although the tread 3 has been described as being vulcanized and bonded to the tread bonding region R with the unvulcanized cushion rubber 4, the present invention is not limited thereto, A vulcanized tread may be provided in the tread adhering region R, and the unvulcanized tread may be vulcanized while being molded with a mold so as to be integrated with the table tread 1.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. For example, in the molding method of the green tire that is the base tire 1 of the present invention, in addition to the method using the molding drum as described above, a mold having the same outer shape as the inner surface shape of the base tire after vulcanization molding In addition, after forming the green tire by arranging the members as described above, the green tire may be covered and vulcanized by an outer mold that surrounds and molds the green tire from the outside. .

1 tire, 3 tread, 4 cushion rubber, 12 carcass,
13 belt layers, 17 side rubber, 18 treads, 20A maximum width,
21 Equator, 31 Lower platen, 32 Lower mold, 34 Upper platen, 35 Upper mold,
A1 tread area, A2 buttress area, A3 side area, A4 bead area.

Claims (7)

In an unvulcanized stand tire mainly having a tread region, a buttress region, a side region, and a bead region,
An unvulcanized tire according to claim 1, wherein the cross-sectional thickness in the side region, the cross-sectional thickness in the buttress region, and the cross-sectional thickness in the tread region are set to be substantially equal.   The unvulcanized table tire according to claim 1, wherein the cross-sectional thicknesses in the range of the buttress region and the tread region are set to be substantially equal from the position of the maximum width portion positioned on the outermost surface in the width direction on the outer surface of the side region. .   The cross-sectional thickness in the range of the side region, the buttress region, and the tread region from the rising portion on the tread region side of the protruding portion that protrudes to the outer surface of the boundary portion between the side region and the bead region is set to be substantially equal. Item 1. An unvulcanized stand tire according to Item 1.   A base tire comprising the unvulcanized base tire according to any one of claims 1 to 3 vulcanized at a uniform temperature over a tread region, a buttress region, and a side region.   The base tire according to claim 4, wherein an uneven portion is formed in a range of the buttress region.   A tire comprising a tread attached to an outer surface of a tread region and a buttress region of the base tire according to claim 4 or 5. A tread is placed on the outer surface of the tread region and buttress region of the base tire according to claim 4 or claim 5 via a cushion rubber and vulcanized, and the tread is adhered to the base tire with the cushion rubber. Tire manufacturing method.

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