JP2012171182A - Method of manufacturing tire, and tire vulcanization molding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of manufacturing a tire, and a tire vulcanization molding device, by which deformation of a groove formed on a tread surface of PCT (precured tread) can be suppressed when vulcanization-molding a tire by using the tire vulcanization molding device before vulcanization molding with the usage of PCT.SOLUTION: In the method of manufacturing the tire, wherein when the tire 2 before vulcanization molding which is formed with the usage of a vulcanized tread (PCT12) is vulcanization-molded, heat and pressure are applied to an inner surface 4 of the tire 2 before vulcanization molding confronting the tread surface 3 of the tire 2 before vulcanization molding placed under the prescribed condition in a mold space of the vulcanization molding device 1 for vulcanization-molding the tire 2, a groove shape deformation suppressing means for suppressing deformation of the groove 5 in vulcanization molding is provided in a space 8 formed between an inner surface 6 of the groove 5 formed on the tread surface 3 and a mold surface 7 of the vulcanization molding device 1.

Description

  The present invention relates to a tire manufacturing method using a vulcanized tread.

A tire tread and a portion other than the tire tread (hereinafter referred to as a case) are prepared separately, and the tire before vulcanization formed by providing a tread on the outer peripheral surface of the case is vulcanized by a vulcanization molding device. A tire manufacturing method is known.
The vulcanization molding apparatus has a molding surface that comes into contact with the surface of the tire before vulcanization molding. Specifically, a mold having a molding surface in contact with the outer surface of the tire before vulcanization molding and a bladder having a molding surface in contact with the inner surface of the tire before vulcanization molding are provided.
When vulcanizing and molding a pre-vulcanized tire formed by providing a vulcanized tread (hereinafter referred to as PCT (precure tread)) on the outer peripheral surface of the case, molding of the vulcanization molding device The tire is vulcanized by applying heat and pressure to the inner surface of the unvulcanized tire facing the tread surface of the unvulcanized tire installed in a predetermined state in the space via a bladder.

JP 2002-361755 A JP-A-10-193471 Japanese Patent Application Laid-Open No. 09-011706 JP 54-124082 A

When vulcanizing and molding a pre-vulcanized tire formed using PCT with a vulcanization molding device, between the inner surface of the groove formed on the tread surface of the PCT and the molding surface of the mold of the vulcanization molding device Therefore, there is a possibility that the bottom of the groove may be deformed so that the bottom side of the groove protrudes toward the space when pressure is applied to the inner surface of the tire through the bladder as described above. The tire performance (drainage, wear resistance, etc.) may not be fully demonstrated.
The present invention relates to a tire manufacturing method and a tire vulcanization method that can suppress deformation of a groove formed on a tread surface of a PCT when a tire before vulcanization molding using PCT is vulcanized and molded by a vulcanization molding apparatus. A sulfur molding apparatus is provided.

The tire manufacturing method according to the present invention is installed in a predetermined state in a molding space of a vulcanization molding apparatus when a vulcanized tire formed using a vulcanized tread is vulcanized. In the tire manufacturing method in which heat and pressure are applied to the inner surface of the tire before vulcanization molding facing the tread surface of the tire before vulcanization molding, the tire is vulcanized and molded, and the tire is formed on the tread surface. Since a groove shape deformation suppression means for suppressing the shape deformation of the groove during vulcanization molding is provided in the space formed between the inner surface of the groove and the molding surface of the vulcanization molding apparatus, the tread surface The deformation of the formed grooves can be suppressed, and a tire with desired performance can be manufactured.
The groove shape deformation suppression means is formed by a gas injected into the space from the outside of the vulcanization molding apparatus during the vulcanization molding, and the predetermined pressure value of the gas is a pressure applied to the inner surface of the tire. Since the value is smaller than the value, the deformation of the groove formed on the tread surface can be suppressed, and the case can be prevented from being deformed by the pressure of the gas injected into the space.
A plurality of gas communication ports are provided at the end of the gas communication passage for communicating the outside of the vulcanization molding apparatus and the space, and the gas communication ports communicate with the space. Since it is arranged at 360 ° / N (the number of gas communication ports arranged at intervals in the tire circumferential direction) in the tire circumferential direction installed in the molding apparatus, deformation of the groove can be suppressed more uniformly. .
Since the groove shape deformation suppressing means is formed of a solid inserted into the groove before the vulcanization molding, it is possible to suppress the deformation of the groove formed on the tread surface and manufacture a tire having a desired performance. It becomes like this.
A tire vulcanization molding apparatus according to the present invention is a tire vulcanization molding apparatus including a mold that forms a molding space in which a tire before vulcanization molding is installed, and is installed in a predetermined state in the molding space. Since it has a communication path that connects the groove formed on the tread surface of the tire before vulcanization molding and the outside of the vulcanization molding device, it is formed between the inner surface of the groove and the molding surface of the vulcanization molding device. Since the groove shape deformation suppressing means such as gas can be supplied from the outside of the vulcanization molding device to the space to be formed, the deformation of the groove formed on the tread surface can be suppressed, and the tire having the desired performance Can be manufactured.

Sectional drawing which shows the vulcanization molding method by a vulcanization molding apparatus. Sectional drawing which shows the specific example of a vulcanization molding apparatus. Sectional drawing which shows the procedure of a vulcanization molding method. Sectional drawing which shows the procedure of a vulcanization molding method. The figure which shows the relationship between a bladder pressure and gas injection pressure.

Embodiment 1
The tire manufacturing method according to the first embodiment is formed by providing a PCT 12 that is a vulcanized tread on the outer peripheral surface of an unvulcanized case (hereinafter referred to as an unvulcanized case) 10 as shown in FIG. A tire 2 before vulcanization molding (hereinafter simply referred to as a tire) 2 is placed in a predetermined state in the molding space of the vulcanization molding apparatus 1, and a bladder 23 is attached to the inner surface 4 of the tire 2 facing the tread surface 3 of the tire 2. Is formed between the inner surface 6 of the groove 5 formed in the tread surface 3 and the molding surface 7 of the mold of the vulcanization molding apparatus 1 when the tire 2 is vulcanized and molded by applying heat and pressure to the tire. A gas as groove shape deformation suppressing means for suppressing shape deformation of the groove 5 during vulcanization molding is injected into the space 8 to be formed.
Specifically, during the vulcanization molding, gas is injected into the space 8 from the outside of the vulcanization molding apparatus 1 using the gas supply device 62, and the gas is injected into the space 8 to be injected into the inner surface 6 of the groove 5. The pressure value of the gas that pushes the pressure is maintained at a value equal to or higher than the atmospheric pressure and smaller than the pressure value applied to the inner surface 4 of the tire 2.
In the tire manufacturing method according to the first embodiment, since the PCT 12 in which the grooves 5 are already formed in the tread surface 3 is used, the molding surface 7 of the mold that comes into contact with the tread surface 3 of the tire 2 is a surface without unevenness (that is, , A vulcanization molding apparatus 1 formed on a surface having no protrusions fitted into the groove 5 is used.
Therefore, a space 8 is generated between the inner surface 6 of the groove 5 formed in the tread surface 3 and the molding surface 7 of the vulcanization molding apparatus 1. Accordingly, when heat and pressure are applied to the inner surface 4 of the tire 2 during the vulcanization molding, there is a possibility that the bottom side of the groove 5 is deformed so as to protrude toward the space 8 side.
Therefore, in the first embodiment, during the vulcanization molding, the space 8 is filled with a gas pressure as a resistor capable of resisting a force that deforms the bottom side of the groove 5 so as to project toward the space.
The mold is provided with a communication path 60 provided so as to communicate with the molding surface 7 of the mold and the outer surface of the mold so as to communicate the outer surface of the mold with the space 8. By connecting the inlet 61 with the communication pipe 63, a supply path for supplying gas from the gas supply device 62 to the space 8 is formed.
Note that air or nitrogen may be used as the gas.

General tires are vulcanized with a vulcanization molding device, which is a raw tire (green tire) formed by combining each member such as bead wire, bead filler, inner liner, carcass, belt 10a, sidewall, shoulder, and tread. Manufactured by molding. In this case, in order to form a groove on the tread surface of the green tire during vulcanization molding, a vulcanization molding apparatus having a projection on the molding surface of the mold that contacts the tread surface of the green tire is used.
On the other hand, the tire 2 to be vulcanized and molded in the embodiment is an unvulcanized tire formed by combining each member such as a bead wire, a bead filler, an inner liner, a carcass, a belt 10a, a sidewall, and a shoulder, excluding a tread. The vulcanized case 10 and a PCT 12 that is a vulcanized tread manufactured separately from the unvulcanized case 10, and the PCT 12 is provided on the tread mounting surface 11 of the unvulcanized case 10. It is formed by.

The unvulcanized case 10 is an unvulcanized rubber component having a general tire configuration excluding the tread.
PCT12 is formed of a band or a ring.
In other words, the PCT 12 formed by the belt body has a width corresponding to the width (tire width) of the tread mounting surface 11 that is the outer peripheral surface of the unvulcanized case 10 and the circumference of the outer peripheral surface of the unvulcanized case 10. A tread mounting surface in which a groove 5 serving as a tread pattern is formed on one surface of a band having a length corresponding to the length in the direction, and the other surface of the band is an outer peripheral surface of the unvulcanized case 10 11 is a vulcanized rubber component formed on an attached surface 13 that is attached by being vulcanized and bonded to 11.
On the other hand, the PCT 12 formed of an annular body is a groove that forms a tread pattern on the outer circumferential surface of the annular body having a width corresponding to the width (tire width) of the tread mounting surface 11 that is the outer circumferential surface of the unvulcanized case 10. 5 is a vulcanized rubber component formed on a mounting surface 13 that is formed by vulcanizing and attaching the inner peripheral surface of the ring body to the tread mounting surface 11 of the unvulcanized case 10.
When the band PCT 12 is used, the tire 2 is formed by wrapping around the outer peripheral surface of the unvulcanized case 10 and connecting the one end and the other end of the band with a connecting body. .
In the case of using the PCT 12 that is an annular body, the tire 2 is formed by fitting the unvulcanized case 10 inside the annular body of the PCT 12, which is preferable because there is no seam in the PCT 12.
The tire 2 formed as described above is vulcanized and molded by the vulcanization molding apparatus 1 to vulcanize and bond the tread mounting surface 11 which is the outer peripheral surface of the unvulcanized case 10 and the mounted surface 13 of the PCT 12. .
In Embodiment 1, PCT12, which is a vulcanized tread, is a fully vulcanized product that has been vulcanized until a desired vulcanization degree is reached, or a desired vulcanization degree that has been vulcanized. The so-called semi-vulcanized product that has not been vulcanized until it reaches

  Next, a specific example of the vulcanization molding apparatus 1 will be described based on FIG. In the following description, one member is defined as “lower” and the other member is defined as “upper”.

  The vulcanization molding apparatus 1 includes a tire inner surface vulcanization molding apparatus (hereinafter referred to as a bladder apparatus) 1A for vulcanization molding of the inner surface 4 of the tire 2 before vulcanization molding, and one side surface of the tire 2 by vulcanization molding. A lower mold device 1B that is a one-side vulcanization molding device, a tread molding device 1C for vulcanizing and molding the tread portion of the tire 2, and the other side surface for vulcanizing and molding the other side surface of the tire 2 An upper mold device 1D, which is a vulcanization molding device, a groove shape deformation suppressing device 1E, and an air supply / discharge device 1F are provided.

  The bladder apparatus 1 </ b> A includes a central column body 20, a first lifting / lowering device 21, a bladder holder 22, a bladder 23, and an energy supply device 70 that supplies thermal energy and pressure energy into the bladder 23.

The center column body 20 includes an outer hollow column body 20a and an inner hollow column body 20b, and the outer hollow column body so that the center axis X of the outer hollow column body 20a coincides with the center axis X of the inner hollow column body 20b. This is a coaxial double tube configuration in which an inner hollow column 20b is provided inside 20a.
The center column body 20 is fixed to the floor surface outside the figure by a fixing means outside the figure so that the center axis X of the outer hollow column body 20a and the inner hollow column body 20b extends in the vertical direction. The

The first elevating device 21 is constituted by, for example, a hydraulic cylinder device.
A cylinder (not shown) of the hydraulic cylinder device is installed inside the inner hollow column body 20b so that the central axis of the piston rod 21a as the lifting body of the hydraulic cylinder device coincides with the central axis X of the inner hollow column body 20b. The piston rod 21a is installed inside the inner hollow column 20b.
Then, the piston rod 21a is moved along the central axis X of the central column body 20 by supplying oil into the cylinder or discharging the oil in the cylinder from the cylinder by control by a hydraulic control device (not shown) of the hydraulic cylinder device. It is configured so that it can be extended upward and retracted downward.

The bladder holder 22 includes a lower holding plate 22a and an upper holding plate 22b.
The lower holding plate 22a is constituted by a circular plate having a through hole 22c formed in a dimension corresponding to the outer peripheral dimension of the outer hollow columnar body 20a at the center of a circle. The upper end of the outer hollow column 20a is positioned inside the through hole 22c of the lower holding plate 22a, and the outer hollow column 20a and the lower holding plate 22a are connected. An annular upper end opening 22t of the outer hollow column 20a communicates with the inside of the bladder 23.
The upper holding plate 22b is configured by a circular plate. The upper end of the piston rod 21a and the upper holding plate 22b are connected so that the center axis of the piston rod 21a and the center of the circle of the circular plate of the upper holding plate 22b coincide.
The outer diameter of the circular plate that forms the lower holding plate 22a and the outer diameter of the circular plate that forms the upper holding plate 22b are formed to be the same, and the outer dimensions are the hole 2h of the tire 2 (the center of the tire 2). It is smaller than the diameter dimension of the hole centered on the shaft (see FIG. 3).

The bladder 23 functions as an energy transmission means for transmitting thermal energy and pressure energy to the inner surface 4 of the tire 2 and is formed by a cylindrical body having both end openings formed of a flexible material such as rubber.
The lower end opening edge portion 23a of the cylindrical body of the bladder 23 and the outer peripheral portion of the circular plate forming the lower holding plate 22a so that the central axis of the cylindrical body of the bladder 23 and the central axis X of the central column body 20 coincide. The upper end opening edge 23b of the cylindrical body of the bladder 23 and the outer peripheral portion of the circular plate forming the upper holding plate 22b are connected in an airtight state.

  The lower mold apparatus 1 </ b> B includes a base 30, a heat insulating part 31, a heating part 32, a lower mold 33, and a guide part 34.

  The base 30 is constituted by a circular flat plate having a through hole 30a through which the central columnar body 20 passes in the center of a circle. The base 30 has an annular shape which is one surface of a circular flat plate so that the center axis X of the central column 20 passing through the through hole 30a of the base 30 coincides with the center of the circle of the base 30. The circular upper surface 30b is fixed to a floor outside the figure via support means outside the figure so that it becomes a horizontal plane.

A heat insulating part 31 is installed on the upper surface 30 b of the base 30, and a heating part 32 is installed on the upper surface of the heat insulating part 31.
A lower mold 33 and a plurality of guide parts 34 are installed on the upper surface of the heating part 32.

  The heating unit 32 includes a structure for applying heat to the lower mold 33, and includes, for example, an unillustrated hot water circulation passage for circulating hot water, an unillustrated electric heater, and the like. That is, the heating unit 32 is connected to a hot water circulation device (not shown) and circulates the hot water through the hot water circulation flow path to transmit the heat of the hot water to the lower mold 33, and the electric heater is connected to a power supply (not shown). And a structure for transmitting the heat of the electric heater to the lower mold 33.

  The heat insulation part 31 suppresses that the heat of the heating part 32 is transmitted to the base 30 side and escapes to the outside. The heat insulation part 31 is made of a material having heat insulation performance, or has a heat insulation structure. .

  The lower mold 33 functions as a side vulcanization molding surface 35 whose upper surface contacts one side surface of the tire 2 and transfers heat to the one side surface. The one side vulcanization molding surface 35 is an annular surface with the central axis X of the central column body 20 as the center. The lower mold 33 includes a main mold 33a for vulcanizing and molding a shoulder portion and a side portion on one side surface of the tire 2, and a bead mold for vulcanizing and molding a bead portion on one side surface of the tire 2. 33b. The lower surface of the lower holding plate 22a of the bladder holder 22 and the bead mold 33b are connected. Since the lower mold 33 is divided into the main mold 33a and the bead mold 33b, the bead mold 33b is heated in order to efficiently transfer heat to the bead portion that is harder to vulcanize than the shoulder portion and the side portion. The bead mold 33b can be formed of a material having high conductivity or a material that can be easily processed into a shape corresponding to a bead portion having a complicated shape as compared with the shoulder portion and the side portion.

  The heat insulating part 31, the heating part 32, and the lower mold 33 are all formed in a circular plate shape having a through hole in the center of the circle, like the base 30, and the center of the circle and the central column body It is installed on the base 30 and supported by the base 30 so that the center axis X of 20 coincides. In addition, the base 30, the heat insulation part 31, the heating part 32, and the lower mold 33 are laminated | stacked as mentioned above, and the members which mutually contact are connected.

  The guide part 34 functions as a guide part when moving a plurality of divided tread mold constituent parts 42 of the tread mold apparatus 1C described later in a direction toward and away from the central axis X of the central column body 20. For example, it is constituted by a groove rail or a protruding rail.

  The tread mold apparatus 1 </ b> C includes a tread mold configuration unit 40 and power transmission means 41. The power transmission means 41 is related to the upper mold apparatus 1D and will be described after the upper mold apparatus 1D is described.

The tread mold constituting unit 40 includes a plurality of divided tread mold constituting units 42.
The divided tread mold constituting part 42 includes a divided tread mold part 43 called a sector mold, a power receiving body 44, a guide means 45, and an urging means 46.

The plurality of divided tread mold portions 43 are provided on the lower mold 33 and the heating portion 32 so as to surround the tread surface 3 of the tire 2 placed in a predetermined state on the one side vulcanization molding surface 35 of the lower mold 33. It is what A tread mold 40 </ b> A is formed by the plurality of divided tread mold portions 43.
A molding surface 7 which is placed in a predetermined state on one side vulcanization molding surface 35 of the lower mold 33 and comes into contact with the tread surface 3 which is the outer peripheral surface of the tire 2 centering on the center of the central column body 20 is divided into a plurality of divisions. It is constituted by an assembly of the respective vulcanization molding surfaces 47 formed in the tread mold part 43.
Each of the vulcanization molding surfaces 47 of the plurality of divided tread mold portions 43 is, for example, each of the central columnar body 20 serving as the center of the tire 2 installed in a predetermined state on one side vulcanization molding surface 35 of the lower mold 33. Contact with the tread surface 3 corresponding to the length of the outer peripheral arc of the tire 2 corresponding to 1 / n degrees of 360 degrees (hereinafter referred to as the angle α), which is an angle of one rotation around the central axis X. For example, if the plurality of divided tread mold portions 43 are eight, the vulcanization molding surface 47 of one divided tread mold portion 43 is a tread corresponding to the outer circumference arc length of the tire 2 corresponding to the angle α = 45 degrees. It is formed in contact with the surface 3.
And when the some division | segmentation tread mold part 43 moves to the direction which approaches the central axis X of the center pillar 20, and each vulcanization molding surface 47 of the some division | segmentation tread mold part 43 contacts the tread surface 3 of the tire 2 The molding surface 7 formed by each vulcanization molding surface 47 of the plurality of divided tread mold portions 43 is a through-hole that contacts the tread surface 3 of the tire 2 (= penetration around the central axis X of the central column body 20). The hole wall surface of the hole).

Each divided tread mold part 43 is individually attached to the power receiver 44.
Each outer surface of the plurality of power receiving bodies 44 forms, for example, a conical surface of a cone centering on the central axis X of the central columnar body 20, and this conical surface functions as the power receiving surface 49. The power receiving surface 49 comes into contact with a power transmitting surface 56 of an outer ring 55 described later as a power transmitting body, and the power receiving surface 49 receives a force from the power transmitting surface 56, whereby a plurality of divided tread mold portions 43 are provided. Moves in a direction approaching the central axis X of the central columnar body 20, and each vulcanized molding surface 47 of the plurality of divided tread mold portions 43 forms a molding surface 7 in contact with the tread surface 3 of the tire 2.

  The guide means 45 is provided on the lower surface of the power receiver 44, and is, for example, a protruding portion that engages with a groove rail as the guide portion 34, or a groove portion that engages with the protruding rail as the guide portion 34, or the like. Consists of.

  The urging means 46 is a means for maintaining the vulcanization molding surface 47 of each divided tread mold portion 43 in a state separated from the tread surface 3. For example, one end is connected to a support portion 46 a fixed to the base 30. The other end is constituted by an elastic means such as a spring connected to the power receiver 44.

Therefore, when the power receiving body 44 of each divided tread mold portion 43 is not receiving force from the power transmission surface 56 of the outer ring 55, each divided tread mold portion 43 is separated from the tread surface 3 by the biasing means 46. (See FIG. 3). When the power receiving body 44 of each divided tread mold portion 43 receives a force from the power transmission surface 56 of the outer ring 55, each divided tread mold portion 43 resists the biasing means 46 and has a central column body. The vulcanization molding surfaces 47 of the plurality of divided tread mold parts 43 come into contact with the tread surface 3 of the tire 2 to form the molding surface 7 (see FIG. 4).
By using the tread mold apparatus 1C having such a plurality of divided tread mold portions 43, the tread surface 3 of the tire 2 can be pressed and held evenly, and a tire with good uniformity can be manufactured.

  The upper mold apparatus 1D includes an upper mold 50, an upper mold support base 51, a heating part 52, a heat insulating part 53, and a second lifting / lowering apparatus 54.

  The upper mold 50 has a lower surface in contact with the other side surface of the tire 2 placed in a predetermined state on the vulcanization molding surface 35 of the lower mold 33, and vulcanized to transmit heat energy and pressure energy to the other side surface. It functions as the molding surface 36. The vulcanization molding surface 36 is an annular surface centered on the central axis X of the central column body 20. As with the lower mold 33, the upper mold 50 includes a main mold 50 a for vulcanizing and molding a shoulder portion and a side portion on the other side surface of the tire 2, and a bead portion on the other side surface of the tire 2. A bead mold 50b for vulcanization molding. The upper surface of the upper holding plate 22b of the bladder holder 22 and the bead mold 50b are connected.

  The upper surface of the upper mold 50 and the lower surface of the upper mold support base 51 are connected. A heating unit 52 is installed on the upper surface of the upper mold support base 51. A heat insulating part 53 is installed on the upper surface of the heating part 52. On the upper surface of the heat insulating portion 53, a connecting body 57 described later is installed.

The heating unit 52 has a structure for applying heat to the upper mold 50 and has the same configuration as the heating unit 32 described above.
The heat insulation part 53 suppresses that the heat of the heating part 52 is transmitted to the connecting body 57 side and escapes to the outside, and has the same configuration as the heat insulation part 31 described above.

  The second lifting device 54 is constituted by, for example, a hydraulic cylinder device. The center part of the circle of the upper mold support 51 is connected to the lower end part of the piston rod 54a as the lifting body of the hydraulic cylinder device so that the central axis of the piston rod 54a and the central axis X of the central column 20 coincide. In addition, a cylinder of the hydraulic cylinder device is installed above the connecting body 57. This cylinder is fixed to a support column (not shown) fixed to the floor. Then, oil is supplied into the cylinder under the control of a hydraulic control device (not shown) of the hydraulic cylinder device, or the oil in the cylinder is discharged from the cylinder, whereby the piston rod 54a is moved to the central axis X of the central column body 20. It is possible to extend along the lower side and to retract toward the upper side.

  The power transmission means 41 of the tread mold apparatus 1 </ b> C includes a connecting body 57 that connects the above-described second lifting device 54, the outer ring 55 as a power transmission body, and the outer ring 55 and the piston rod 54 a of the second lifting device 54. With.

The connecting body 57 is formed in a circular flat plate having a through hole 57a through which the lower end of the piston rod 54a passes in the center of the circle so that the center of the through hole 57a coincides with the central axis X of the central column body 20. Provided.
The connecting body 57 is directly connected to the lower end portion of the piston rod 54a by a connecting means (not shown) or is connected to the upper surface of the heat insulating portion 53 so as to move up and down by raising and lowering the piston rod 54a. By being connected to the lower end portion of the piston rod 54a, the lifting / lowering operation is performed in conjunction with the lifting / lowering of the piston rod 54a.

  The outer ring 55 is formed by a cylindrical body that is open at both ends, and the upper end opening end surface of the cylindrical body and the connecting body 57 are arranged so that the central axis of the cylindrical body of the outer ring 55 coincides with the central axis X of the central column body 20. The lower surface is connected. The cylindrical inner surface of the outer ring 55 on the lower end opening end face side of the cylindrical body is formed in a conical surface with the central axis X of the central column 20 as the central axis. This conical surface functions as the power transmission surface 56.

  Accordingly, by lowering the piston rod 54a of the second elevating device 54, the power transmission surface 56 of the outer ring 55 comes into contact with the power receiving surface 49 of the power receiving body 44 of each divided tread mold portion 43 from the lower end side. As a result, the plurality of divided tread mold parts 43 move toward the central axis X of the central column body 20, the molding surface 7 and the tread surface 3 of the tire 2 come into contact with each other, and the vulcanization molding surface 36 of the upper mold 50 The other side surface of the tire 2 comes into contact.

  At the time of vulcanization molding of the tire 2, the groove shape deformation suppressing device 1E passes through the divided tread mold portion 43, the power receiving body 44, and the outer ring 55, and passes through the space 8 of the groove 5 and the outer peripheral surface of the outer ring 55 (vulcanized). Gas communication passage 60 communicating with the outside of the sulfur molding device), gas supply device 62, gas inlet 61 which is one end of communication passage 60 opened on the outer peripheral surface of outer ring 55, and gas in gas supply device 62 A communication pipe 63 that communicates with the outlet 62 a and a control device 64 are provided.

When the groove 5 formed in the tread surface 3 is an annular groove 5 that goes around the outer peripheral surface of the tire 2 that is the tread surface 3, one or more communication paths 60 that communicate with the space 8 of the annular groove 5 are provided. The gas may be injected into the space 8 through the communication path 60. In this case, the communication path 60 may be provided at two locations so as to correspond to the portions 180 ° apart from each other on the circumference of the tread surface 3, or at the portions 120 ° apart from each other on the circumference of the tread surface 3. Three locations may be provided so as to correspond, or three or more locations may be provided.
That is, in the case where a plurality of gas communication passages 60 are provided in the circumferential direction of the tire installed in the vulcanization molding apparatus 1 to communicate the outside of the vulcanization molding apparatus 1 with the space 8 of the groove 5, The gas communication port 61a provided on the molding surface 7 of the tread mold 40A so as to communicate with the space 8 at the end (end) is 360 ° / N (in the tire circumferential direction) in consideration of practical manufacturing errors and the like. By uniformly disposing the gas communication ports 61a arranged at intervals in the tire circumferential direction at intervals, deformation of the grooves can be more uniformly suppressed.

  When the grooves 5 formed in the tread surface 3 are independent grooves 5 provided independently on the outer peripheral surface of the tire 2 that is the tread surface 3, the communication path 60 that communicates with the space 8 of these independent grooves 5. And a gas may be injected into the space 8 through the communication path 60.

  The control device 64 includes a pressure value (hereinafter referred to as bladder pressure) based on thermal energy or pressure energy supplied from the energy supply device 70 into the bladder 23 and a pressure value of gas supplied from the gas supply device 62 into the space 8 ( Hereinafter, the energy supply device 70 and the gas supply device 62 are controlled by inputting the gas injection pressure. The energy delivery port of the energy supply device 70 and the hollow portion of the outer hollow column body 20a communicate with each other through the communication tube 71, whereby the communication tube 71 and the outer hollow column body are controlled from the energy supply device 70 controlled by the control device 64. Energy can be supplied into the bladder 23 through the hollow portion 20a.

  The air supply / discharge device 1 </ b> F exists between the outer surface of the bladder 23 and the inner surface 4 of the tire 2 in order to improve the adhesion between the outer surface of the bladder 23 and the inner surface 4 of the tire 2 during vulcanization molding. A device for discharging gas and supplying gas between the outer surface of the bladder 23 and the inner surface 4 of the tire 2 in order to release the contact between the outer surface of the bladder 23 and the inner surface 4 of the tire 2 after vulcanization molding. It is. For example, the air supply / discharge device 1 </ b> F allows the communication path 81 formed in the bead mold 33 b of the lower mold 33, the supply / discharge pump 82, and the discharge port and suction port of the pump 82 to communicate with the communication path 81. A communication pipe 83 and a control device 64 are provided. By controlling the pump 82 with the control device 64, the gas discharge operation and the gas supply operation can be realized.

Next, a tire vulcanization molding method will be described.
As shown in FIG. 3A, by raising the piston rod 21 a of the first lifting device 21, the bladder 23 forms a cylindrical body with the central axis X of the central column body 20 as the central axis. The outer diameter of the cylindrical body is smaller than the diameter of the hole 2 h of the tire 2. In this state where the piston rod 21a is raised, the tire 2 is dropped so that the cylindrical body of the bladder 23 penetrates the hole 2h of the tire 2, and the tire 2 is fixed to the predetermined vulcanization surface 35 of the lower mold 33. Install in position.
Then, as shown in FIG. 3B, the bladder 23 is loosened by lowering the piston rod 21a.
Next, as shown in FIG. 4A, the piston rod 54a of the second lifting device 54 is lowered. Thereby, the power transmission surface 56 of the outer ring 55 and the power receiving surface 49 of the power receiving body 44 of each divided tread mold portion 43 come into contact with each other, and each divided tread mold portion 43 faces the central axis X of the central column body 20. The molding surface 7 and the tread surface 3 of the tire 2 come into contact with each other. Further, the upper mold 50 is lowered, and the vulcanization molding surface 36 of the upper mold 50 and the other side surface of the tire 2 come into contact with each other. Therefore, the outer surface of the tire 2 and the molding surfaces 35; 7; 36 of the molds 33; 40A;
Next, by controlling the energy supply device 70 with the control device 64 and supplying, for example, steam to the inside of the bladder 23, and then setting gas or hot water to press the inner surface of the tire 2 to a predetermined pressure value. As shown in FIG. 4B, the bladder 23 enters the inner space of the tire 2 and contacts the entire inner surface 4 of the tire 2. At this time, the air supply / discharge device 1 </ b> F is operated to discharge the gas existing between the outer surface of the bladder 23 and the inner surface 4 of the tire 2, whereby the adhesion between the outer surface of the bladder 23 and the inner surface 4 of the tire 2. To improve.
Then, the energy supply device 70 is controlled to supply heat and pressure to the inside of the bladder 23 as described above, and the control device 64 controls the gas supply device 62 to supply gas into the space 8, thereby heating the heating unit. 32; 52 is heated to supply heat to the lower mold 33 and the upper mold 50.
As described above, the tire 2 is vulcanized and molded from the inner surface 4 side of the tire 2 by the heat and pressure supplied into the bladder 23, and the tire 2 is tired by the heat and pressure supplied to the lower mold 33 and the upper mold 50. The tread mounting surface 11 of the unvulcanized case 10 and the mounted surface 13 of the PCT 12 are vulcanized and bonded to obtain a vulcanized tire.

The control device 64 controls the gas injection pressure P2 by the gas supply device 62 so as to have a relationship as shown in FIG. That is, the control device 64 controls the gas injection pressure P2 to be always lower than the bladder pressure P1 during vulcanization, and the pressure difference between the bladder pressure P1 and the gas injection pressure P2 is substantially predetermined during vulcanization. Control to maintain the value. For example, in the case of TBR, control is performed so that 0 <differential pressure <0.2 MPa.
Specifically, as shown in FIG. 5, the control device 64 controls the energy supply device 70 to start the supply of energy into the bladder 23, and then controls the gas supply device 62 after a lapse of a predetermined time. Begin supplying gas into 8. Then, the control device 64 controls the energy supply device 70 and the gas supply device 62 so that the gas injection pressure P2 approaches the bladder pressure P1 and the gas injection pressure P2 does not become larger than the bladder pressure P1.
As described above, by controlling the gas injection pressure P2, the deformation of the groove 5 can be suppressed, and the case can be prevented from being deformed by the pressure of the gas injected into the space 8.

  According to the first embodiment, in the method of vulcanizing and molding the tire 2 using the PCT 12, the space generated between the inner surface 6 of the groove 5 formed in the tread surface 3 and the molding surface 7 of the vulcanization molding apparatus 1. 8 is filled with a gas pressure that resists the bladder pressure P1, and vulcanized and molded, so that deformation of the groove 5 formed on the tread surface 3 of the PCT 12 can be suppressed, and a tire with desired performance can be manufactured. become.

  A first pressure sensor (not shown) that is attached to the inner surface of the bladder 23 and detects the pressure value in the bladder 23 and a pressure sensor that is attached to the molding surface 7 of the tread mold 40A and detects the pressure value in the space 8 are not shown. A pressure control means including the second pressure sensor and a control device 64 that inputs a pressure value from each pressure sensor and controls the energy supply device 70 and the gas supply device 62 may be used. If the pressure control means is used, the internal pressure in the bladder 23 and the internal pressure in the groove 5 can be known accurately, so that these pressures can be controlled more accurately.

Embodiment 2
As the groove shape deformation suppressing means, the groove 5 of the tire 2 may be filled with a solid before vulcanization molding. For example, before the tire 2 is installed at a predetermined position in the vulcanization molding space of the vulcanization molding apparatus 1, a solid material such as silicon formed so as to be fitted in the groove 5 is fitted in the groove 5. It ’s best to keep it in the middle. Even in this case, since the solid filled in the groove 5 of the tire 2 resists the bladder pressure P1 during vulcanization molding, deformation of the groove 5 formed on the tread surface 3 of the PCT 12 can be suppressed. Thus, a tire having a desired performance can be manufactured.

  The tire 2 is vulcanized using a vulcanization molding device having a molding surface having a projection for insertion into the groove 5 formed in the tread surface 3 of the PCT 12 in the tire 2 before vulcanization molding. It is also possible to do. However, in this case, it is necessary to align the grooves 5 of the tread surface 3 of the tire 2 with the protrusions on the molding surface that cannot be deformed, and there is a problem that the number of operations increases, and only tires with groove patterns that match the protrusions are vulcanized. The problem of not being able to occur arises. On the other hand, the present invention can solve the problem.

  In addition, as the vulcanization molding apparatus 1, you may use the vulcanization molding apparatus 1 comprised by the upper mold 1Y and the lower mold 1X as shown in FIG.

  In the above description, the case where the unvulcanized case 10 and the PCT 12 are used to form the tire 2 before vulcanization molding and the tire 2 is vulcanized and molded is described. The present invention can also be applied to a case where a tire before vulcanization molding is formed using PCT12 and complete vulcanization or semi-vulcanization) and vulcanization molding of the tire.

  Further, a liquid may be used as the groove shape deformation suppressing means for filling the space 8 to resist the bladder pressure P1 during vulcanization molding.

1 vulcanization molding equipment, 2 tires, 3 tread surfaces, 4 tire inner surfaces, 5 grooves,
6 inner surface of groove, 7 molding surface, 8 space, 12 PCT, 60 communication path.

Claims (5)

When a pre-vulcanized tire formed using a vulcanized tread is vulcanized and molded, the tread surface of the pre-vulcanized tire installed in a predetermined state in the molding space of the vulcanization molding device In the manufacturing method of the tire which vulcanizes and molds the tire by applying heat and pressure to the inner surface of the tire before facing the vulcanized mold,
Groove shape deformation suppressing means for suppressing deformation of the groove shape during vulcanization molding in a space formed between the inner surface of the groove formed on the tread surface and the molding surface of the vulcanization molding apparatus. A method for manufacturing a tire, comprising:   The groove shape deformation suppression means is formed by a gas injected into the space from the outside of the vulcanization molding apparatus during the vulcanization molding, and the predetermined pressure value of the gas is a pressure applied to the inner surface of the tire. The tire manufacturing method according to claim 1, wherein the value is smaller than the value.   A plurality of gas communication ports are provided at the end of the gas communication passage for communicating the outside of the vulcanization molding apparatus and the space, and the gas communication ports communicate with the space. The tire circumferential direction installed in the molding apparatus is arranged at an interval of 360 ° / N (the number of gas communication ports arranged at intervals in the tire circumferential direction). Tire manufacturing method.   The tire manufacturing method according to claim 1, wherein the groove shape deformation suppressing means is formed of a solid inserted into the groove before the vulcanization molding. In a tire vulcanization molding apparatus equipped with a mold that forms a molding space where a tire before vulcanization molding is installed,
The tire is provided with a communication path that communicates a groove formed in a tread surface of a tire before vulcanization molding installed in a predetermined state in the molding space and the outside of the vulcanization molding apparatus. Sulfur molding equipment.

Images