JP6492853B2 - Pneumatic tire molding method and apparatus - Google Patents

Description

  The present invention relates to a method and apparatus for forming a pneumatic tire, and more specifically, when a green tire is formed by joining a belt member formed in a cylindrical shape in advance to an outer peripheral surface of a cylindrical intermediate green tire. The present invention relates to a method and an apparatus for forming a pneumatic tire that can turn up a band member more reliably and contribute to improvement in productivity by reducing maintenance frequency.

  A pneumatic tire is manufactured by vulcanizing a green tire. As a method of forming this green tire, an intermediate green comprising a cylindrical band member having a carcass material disposed on the outer peripheral side of an inner liner and a pair of bead members disposed at both ends of the band member in the cylinder axial direction. A method is known in which a tire is molded, and then a belt member formed in a cylindrical shape is disposed so as to be extrapolated to the intermediate green tire and joined to the outer peripheral surface of the intermediate green tire (for example, Patent Documents). 1 and 2).

  In this molding method, when the intermediate green tire is molded, the central portion in the cylinder axial direction of the cylindrical band member is inflated. Next, by inflating the turn-up bladder, both ends of the band member in the cylinder axis direction are turned up so as to be in close contact with the opposite band member portions, and each bead member is wrapped with a carcass material and is a cylindrical intermediate green tire Is molded. Next, after placing a belt member formed in a cylindrical shape in advance on the intermediate green tire, the inner peripheral surface of the belt member is joined to the outer peripheral surface of the intermediate green tire to form a green tire.

  If the central portion of the band member in the cylinder axis direction is excessively bulged during turn-up, the cylindrical belt member cannot be extrapolated to the intermediate green tire in a subsequent process. Therefore, an annular restricting body is disposed on the outer peripheral side of the central portion in the cylinder axial direction of the band member, and excessive swelling of the band member is restricted by this restricting body. However, the inflated turn-up bladder may come into contact with the regulating body, and there is a problem that the turn-up bladder is damaged if the contact between the two is repeated. This necessitates frequent maintenance of the turn-up bladder. If the turn-up bladder is damaged, the tire molding process is interrupted and productivity is reduced. Furthermore, when the bending rigidity of the carcass material or the like is increased to some extent, it becomes difficult for the turn-up bladder to inadequately adhere both ends of the turned-up band member in the cylinder axis direction to the opposing band member portions. There was a problem.

JP 2004-106644 A JP 2012-86487 A

  It is an object of the present invention to more reliably turn up a band member when a green tire is formed by joining a cylindrical member formed in advance to an outer peripheral surface of a cylindrical intermediate green tire. Another object is to provide a method and an apparatus for forming a pneumatic tire that contributes to the improvement of productivity by reducing the frequency of maintenance.

In order to achieve the above object, the pneumatic tire molding method of the present invention is configured to remove the bead members at predetermined positions on both ends in the cylinder axial direction of the cylindrical band member in which the carcass material is disposed on the outer peripheral side of the inner liner. Then, an annular restricting body is arranged on the outer peripheral side of the band member to inflate the central portion in the cylinder axial direction of the band member, and the central portion of the band member in the cylindrical axis direction of the band member is expanded by the restricting body. In a state where the bulging amount is restricted, the pair of bead members are turned into the carcass by turning up the portions on the outer side in the cylinder axis direction from the positions where the bead members are installed at both ends in the cylinder axis direction of the band member. A belt formed in a cylindrical shape in advance with respect to the outer peripheral surface of the intermediate green tire after enclosing with a material to form a cylindrical intermediate green tire and then retracting the regulating body In a method for forming a pneumatic tire in which green tires are formed by joining the inner peripheral surfaces of materials, the outer side in the cylinder axis direction of the band member before the turn-up is spaced apart in the cylinder axis direction in the cylinder axis direction. A plurality of extending push-up levers are arranged, and these push-up levers are moved toward the center side in the cylinder axial direction of the band member and rotated outwardly in the radial direction of the band member around the end opposite to the moving direction. by moving the push-up lever moving direction side end portion is abutted to turn up to the band member, at that time, the moving direction side end portion of the push-up lever, and the inner peripheral surface of the regulating member A radial direction of the band member centered on an end opposite to the movement direction of the push-up lever while moving the push-up lever in the cylinder axis direction while entering between the expanding outer peripheral surfaces of the band member Outside The rotation is regulated by the regulating member and performing the turn-up.

The pneumatic tire molding apparatus according to the present invention includes a molding drum in which a cylindrical band member having a carcass material laminated on the outer peripheral side of an inner liner is installed on the outer peripheral surface, and both ends of the band member in the cylinder axial direction are turned. A turn-up mechanism that moves up, and a ring that is movably installed between a set position in the center portion in the cylinder axial direction on the outer peripheral side of the band member installed on the outer peripheral surface of the forming drum and a retracted position that deviates from the set position And a transfer device that conveys a belt member formed in a cylindrical shape in advance to the molding drum. The molding drum has bead set portions at both ends in the drum axial direction, and the turn-up mechanisms are respectively An outer peripheral surface of the intermediate green tire formed on the molding drum is joined to the outer peripheral surface of the belt member, and the inner peripheral surface of the belt member is bonded to the green In the pneumatic tire molding apparatus configured to mold the tire, the turn-up mechanism includes a plurality of push-up levers arranged in the circumferential direction of the drum and extending in the drum axial direction, and the push-up levers A moving mechanism that moves the drum toward the center in the drum axial direction of the molding drum, and when the intermediate green tire is molded, a central portion in the cylinder axial direction of the band member disposed on the outer peripheral surface of the molding drum While expanding, in a state where the amount of bulging is regulated at the central portion in the cylinder axial direction of the band member by the regulating body arranged at the set position, the push-up lever is moved toward the central side in the drum axial direction, The push-up lever is rotated outward in the drum radial direction around the end on the side opposite to the movement direction of the push-up lever, and the end in the movement direction on the end in the cylinder axis direction of the band member It is brought into contact with both end portions in the arrangement of the turn-up, and enter between the moving direction side end portion of the push-up lever, the outer peripheral surface of the band member that expands the inner peripheral surface of the regulating member The turn-up is performed by restricting the rotation of the band member outward in the radial direction around the end opposite to the movement direction of the push-up lever by the restricting body while moving the push-up lever in the cylinder axis direction. It is characterized by having the structure which performs .

  According to the present invention, a push-up lever is provided at both end portions of the band member in the cylinder axis direction while the amount of bulging at the center portion in the tube axis direction of the band member that is inflated when the intermediate green tire is molded is regulated by the regulating body. Since the turn-up mechanism is brought into contact with the regulating body, the possibility that the turn-up mechanism is damaged and does not function even if the push-up lever comes into contact with the regulating body is much lower than that in the case of using the turn-up bladder. Therefore, the maintenance frequency of the turn-up mechanism can be reduced. Further, it is advantageous to prevent the molding process from being interrupted due to a failure of the turn-up mechanism, which contributes to an improvement in tire productivity. Furthermore, even when the bending rigidity of the carcass material or the like is high, the band member can be turned up more reliably as compared with the case where the turn-up bladder is used.

It is explanatory drawing which illustrates the outline | summary of the shaping | molding apparatus of the pneumatic tire of this invention by a longitudinal cross-sectional view. It is explanatory drawing which illustrates the shaping | molding drum and regulating body of FIG. 1 by a side view. It is explanatory drawing which shows the modification of a regulation body by a side view. It is explanatory drawing which illustrates the state which extrapolated the regulation body to the band member by the longitudinal cross-sectional view. It is explanatory drawing which illustrates the process expanded in the state which controlled the swelling amount of the cylinder axial direction center part of a band member by a longitudinal cross-sectional view. It is explanatory drawing which illustrates the process of turning up the direction both ends of a band member by a longitudinal cross-sectional view. It is explanatory drawing which illustrates the process of joining the inner peripheral surface of a belt member to the outer peripheral surface of an intermediate | middle green tire by sectional view. It is explanatory drawing which shows another embodiment of a turnup process by a longitudinal cross-sectional view.

  Hereinafter, a pneumatic tire molding method and molding apparatus of the present invention will be described based on the embodiments shown in the drawings.

  The intermediate green tire G1 is formed using the pneumatic tire forming apparatus of the present invention illustrated in FIGS. 1 and 2, and then the intermediate green tire G1 is processed to form the green tire G2. The molding apparatus includes a molding drum 1, a turn-up mechanism 3, an annular regulation body 8, and a transfer device 9 that conveys a belt member 15 formed in a cylindrical shape in advance to the molding drum 1. The turn-up mechanism 3 and the regulating body 8 are used when molding the intermediate green tire G1, and the transfer device 9 is used when molding the green tire G2.

  The forming drum 1 has a pair of side drum portions 2 arranged at intervals in the drum axis direction. Each side drum portion 2 is provided with a bead set portion 2a that can be expanded and contracted in the drum radial direction. The bead setting portion 2a is formed continuously or intermittently in the drum circumferential direction.

  A turn-up mechanism 3 is installed on the outer side in the drum axis direction of each bead set portion 2a disposed at both ends in the drum axis direction of the forming drum 1. The turn-up mechanism 3 has a plurality of push-up levers 4 that are arranged at intervals in the drum circumferential direction and extend in the drum axis direction, and move these push-up levers 4 toward the center side in the drum axis direction of the forming drum 1. And a moving mechanism 7.

  The push-up lever 4 is formed of a rigid body such as metal or hard resin. The position of the push-up lever 4 in the drum axis direction is controlled by the moving mechanism 7 and can be moved to an arbitrary position and fixed.

  In this embodiment, a pressure roller 5a is provided at the end in the moving direction of the push-up lever 4 that moves toward the center in the drum axis direction of the forming drum 1, and a rotating shaft 5b is provided at the end opposite to the moving direction. It has been. The push-up lever 4 pivots outward in the drum radial direction around the pivot shaft 5b. The push-up levers 4 are provided, for example, at an equal pitch with a central angle of 2 ° to 5 ° in the drum circumferential direction.

  The push-up lever 4 is fitted with a diameter expansion suppression ring 6 formed of rubber, a spring or the like. The diameter expansion suppression ring 6 may be single or plural. In this embodiment, a plurality of diameter expansion restraining rings 6 are arranged at intervals in the drum axis direction.

  The restricting body 8 of this embodiment is formed by a plurality of arc-shaped segments 8a, 8b, 8c, and is formed into an annular shape by connecting these segments 8a, 8b, 8c in a circumferentially continuous state. . The restricting body 8 is not a structure divided into a plurality of segments 8a, 8b, 8c as in this embodiment, but an integrated torus can also be used.

  The restricting body 8 is not limited to a continuously continuous form in the circumferential direction, and may be formed by a plurality of arc-shaped segments 8a, 8b, 8c arranged at intervals in the circumferential direction as illustrated in FIG. it can. In the case of the annular regulating body 8 intermittent in the circumferential direction in this way, the total arc length of all the segments 8a, 8b, 8c is 50% or more of the circumferential length when the annular shape is formed without a break. It is necessary to be.

  Further, the number of restricting bodies 8 is not limited to one, and a plurality of restricting bodies 8 can be arranged in the drum axis direction. In this case, the plurality of regulating bodies 8 are configured to move independently and separately.

  Below, an example of the procedure of the shaping | molding method of the pneumatic tire of this invention is demonstrated.

  First, as illustrated in FIG. 4, a cylindrical band member 10 in which a carcass material 12 is disposed on the outer peripheral side of the inner liner 11 is prepared. More specifically, the side member 14 is disposed on the innermost peripheral side of both ends of the carcass material 12 in the cylinder axis direction. For the band member 10, other necessary members are used as appropriate.

  The band member 10 is arranged on the outer peripheral surface of the forming drum 1 as illustrated in FIG. 4, and the bead member is placed at a predetermined position (a position corresponding to the bead set portion 2 a) at each end of the band member 10 in the cylinder axis direction. 13 is installed by extrapolation. The bead member 13 is configured by an annular bead and a bead filler bonded to the outer peripheral side of the bead, and temporarily presses the inner peripheral surface of the bead to the outer peripheral surface of the band member 10. The band member 10 can be molded on the molding drum 1 or can be molded at another location.

  Next, as illustrated in FIG. 5, the annular restriction body 8 is disposed at a predetermined set position on the outer peripheral side of the band member 10. Next, air is injected into the inside of the band member 10 to expand the central portion of the band member 10 in the cylinder axis direction, and at least one side drum portion so as to reduce the interval between the pair of side drum portions 2 in the drum axis direction. Move 2. As a result, the central portion in the cylinder axis direction of the band member 10 (the inner liner 11 and the carcass material 12) expands to the outer peripheral side, but comes into contact with the inner peripheral surface of the restricting body 8 and the amount of expansion is restricted. .

  In this state, as illustrated in FIG. 6, the push-up lever 4 is moved toward the center in the drum axial direction of the forming drum 1, and is rotated radially outward of the band member 10 about the rotation shaft 5 b. As a result, the pressure roller 5a at the end in the moving direction of the push-up lever 4 is in contact with the inner peripheral surface of the band member 10, and the positions of the bead members 13 at both ends in the cylinder axis direction of the band member 10 are set. Turn up the outer part of the cylinder axis.

  The band member 10 that has been turned up is pressed against a portion of the opposing band member 10 by the pressing force of the pressing roller 5a, and the pair of bead members 13 are wrapped with the carcass material 12 to form the cylindrical intermediate green tire G1. . In this turn-up process, the push-up lever 4 is restrained from rotating radially outward by the diameter expansion restraining ring 6, and both ends of the band member 10 in the cylinder axis direction are firmly turned up.

  Next, the regulating body 8 at the set position is retracted to the retracted position away from the intermediate green tire G1. As illustrated in FIG. 7, the belt member 15 formed in a cylindrical shape in advance is transferred to the intermediate green tire G <b> 1 by the transfer machine 9. The belt member 15 is formed by laminating a tread rubber 17 on the outer peripheral surface of the belt material 16. Other necessary members are appropriately used for the belt member 15.

  The transferred belt member 15 is extrapolated to the intermediate green tire G1, the intermediate green tire G1 is further expanded radially outward, and the inner peripheral surface of the belt member 15 is joined to the outer peripheral surface of the green tire G2. Is molded. The intermediate green tire G1 and the belt member 16 are firmly joined by a stitcher or the like. The molded green tire G2 is placed in a vulcanization mold and then vulcanized at a predetermined temperature and pressure to complete a pneumatic tire.

  As described above, according to the present invention, the push-up lever 4 is brought into contact with both ends of the band member 10 in the cylinder axis direction so that the turn-up mechanism 3 is damaged even if the push-up lever 4 contacts the regulating body 8. Thus, the possibility of not functioning is much lower than when using a turn-up bladder. Further, since the position of the push-up lever 4 in the drum axis direction is accurately controlled by the moving mechanism 7, the contact of the push-up lever 4 with the regulating body 8 itself is avoided.

  Therefore, the maintenance frequency of the turn-up mechanism 3 can be reduced. Further, it is possible to avoid the turn-up mechanism 3 from failing and interrupting the molding process, which contributes to improvement in tire productivity. In addition, even when the bending rigidity of the carcass material 12 or the like is high, the band member 10 can be more reliably turned up as compared with a molding method using a turn-up bladder.

  A turn-up may be performed as illustrated in FIG. In this embodiment, the moving direction side end portion (pressure-bonding roller 5a) of the push-up lever 4 is inserted between the inner peripheral surface of the regulating body 8 and the outer peripheral surface of the expanding band member 10. Then, while the push-up lever 4 is moved in the cylinder axis direction, the restricting body 8 regulates the rotation of the band member 10 around the turning shaft 5b in the radial direction and the turn-up is performed. Yes.

  In this embodiment, the pressure roller 5 a comes into contact with and supports the inner peripheral surface of the restricting body 8, and the restricting body 8 functions as the diameter expansion suppressing ring 6. Therefore, both ends of the band member 10 in the cylinder axis direction can be turned up more strongly. Therefore, even a tire having a particularly high bending rigidity such as the carcass material 12 can be stably turned up and molded.

  As illustrated in FIG. 3, when a plurality of arc-shaped segments 8 (8 a to 8 c) are arranged at intervals in the circumferential direction, the arc length of at least one segment 8 is set to the arc length of another segment 8. It is good to make it different. For example, the arc lengths of all the segments 8 are made different from each other. As a result, the intermediate green tire G1 (and thus the green tire G2) to be molded has a shape in which the constituent members (mainly the carcass material 12) approximate to a regular polygon shape due to the segments 8 used when molding. Such adverse effects do not occur.

  As a result, the manufactured tire is not adversely affected. Therefore, it is possible to prevent a problem that an excessive amplitude is generated in the tire at a specific frequency during traveling, which is advantageous in reducing RFV. The number of segments 8 is not particularly limited as long as it is plural, but for example, it is about 3 to 11, preferably 3 or more. By making the number of segments 8 a prime number of 3 or more, it becomes more advantageous to reduce the RFV of the manufactured tire.

DESCRIPTION OF SYMBOLS 1 Molding drum 2 Side drum part 2a Bead set part 3 Turn-up mechanism 4 Push-up lever 5a Pressure roller 5b Rotating shaft 6 Diameter expansion suppression ring 7 Moving mechanism 8 Restriction body 8a, 8b, 8c Segment 9 Transfer machine 10 Band member 11 Inner Liner 12 Carcass material 13 Bead member 14 Side member 15 Belt member 16 Belt material 17 Tread rubber G1 Intermediate green tire G2 Green tire

Claims (8)

A bead member is extrapolated and installed at predetermined positions on both ends in the cylinder axial direction of the cylindrical band member on which the carcass material is disposed on the outer peripheral side of the inner liner, and then an annular restriction is provided on the outer peripheral side of the band member. A cylindrical body of the band member in a state in which the bulging amount of the central portion in the cylinder axial direction of the band member is regulated by the regulating body while the body is disposed and the central portion in the cylindrical axis direction of the band member is expanded. A cylindrical intermediate green tire is formed by wrapping the pair of bead members with the carcass material by turning up a portion on the outer side in the cylinder axis direction from the position where the bead members are installed at both ends. A pneumatic tie for forming a green tire by joining the inner peripheral surface of a belt member formed in a cylindrical shape in advance to the outer peripheral surface of the intermediate green tire after the regulating body is retracted. In the method of molding,
Before the turn-up, a plurality of push-up levers extending in the cylinder axis direction are disposed on both outer sides in the cylinder axis direction of the band member before the turn-up, and these push-up levers are arranged in the cylinder axis direction of the band member. Move toward the center side and rotate radially outward of the band member around the opposite end in the moving direction so that the end in the moving direction of the push-up lever contacts the band member. At the time, the end of the push-up lever in the moving direction is inserted between the inner peripheral surface of the restricting body and the outer peripheral surface of the expanding band member, and the push-up lever is moved. While turning in the cylinder axis direction, the turn-up is performed by regulating the rotation of the band member radially outward about the end opposite to the movement direction of the push-up lever by the regulating body. To enter Method of molding a tire.   The method for forming a pneumatic tire according to claim 1, wherein an annular regulating body that is continuous in a circumferential direction is used as the regulating body.   The method for forming a pneumatic tire according to claim 1, wherein a plurality of arc-shaped segments arranged at intervals in the circumferential direction are used as the restricting body.   The pneumatic tire molding method according to claim 3, wherein the arc length of at least one segment among the plurality of arc-shaped segments is made different. A forming drum in which a cylindrical band member laminated with a carcass material on the outer peripheral side of the inner liner is installed on the outer peripheral surface; a turn-up mechanism for turning up both ends of the band member in the cylinder axis direction; An annular restricting body that is movably installed between a set position of the central portion in the cylinder axial direction on the outer peripheral side of the band member installed on the outer peripheral surface and a retracted position that deviates from the set position, and is previously formed in a cylindrical shape. A transfer device that conveys the belt member to the forming drum, the forming drum has bead set portions at both ends in the drum axial direction, and the turn-up mechanism is installed on the outer side in the drum axial direction of each bead set portion. A pneumatic tie configured to form a green tire by joining an inner peripheral surface of the belt member to an outer peripheral surface of an intermediate green tire molded on the molding drum. In the molding apparatus,
The turn-up mechanism includes a plurality of push-up levers that are arranged at intervals in the drum circumferential direction and extend in the drum axial direction, and a moving mechanism that moves the push-up levers toward the drum axial center of the forming drum. And with
When forming the intermediate green tire, the cylinder shaft of the band member is formed by the restricting body arranged at the set position while inflating the central portion in the cylinder axis direction of the band member arranged on the outer peripheral surface of the forming drum. The bulging amount is regulated at the center in the direction, and the push-up lever is moved toward the center in the drum axial direction, and the push-up lever is moved around the end opposite to the movement direction of the push-up lever. It is configured to turn up by turning outward in the direction and abutting both ends of the band member in the cylinder axial direction of the band member , and the movement direction side end of the push-up lever The gap between the inner peripheral surface of the body and the outer peripheral surface of the swollen band member, while moving the push-up lever in the cylinder axis direction, with the end on the side opposite to the movement direction of the push-up lever as the center Ba Molding apparatus of a pneumatic tire of the rotation of the radially outer de member is regulated by the regulating member, characterized in that the configuration in which the turn-up. The pneumatic tire molding apparatus according to claim 5 , wherein the restricting body is formed of an annular restricting body that is continuous in a circumferential direction. The pneumatic tire molding apparatus according to claim 5 , wherein the restricting body includes a plurality of arc-shaped segments arranged at intervals in the circumferential direction. The pneumatic tire molding device according to claim 7 , wherein the arc length of at least one of the plurality of arc-shaped segments is different.

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