JP2006076054A - Method and apparatus for manufacturing pneumatic tire - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a manufacturing apparatus of a pneumatic tire capable of developing high durability in its bead part by certainly winding a rubber reinforcing member containing a carcass band having a bending processing part around a bead ring, and a manufacturing method of the pneumatic tire. <P>SOLUTION: The manufacturing apparatus 1 of the pneumatic tire is equipped with a molding drum 3 having a bladder 2, a bead setter 6, a bead lock 7 and a winding accelerating means 8. The rubber reinforcing member 5 having the bending processing part 4 bent outwardly is formed on the molding drum 3. The bead setter 6 holds the bead ring 9 in a separable manner to set the bead ring 9 on the carcass band at a predetermined position while elastically deforming the bending processing part 4. The bead lock 7 is moved to the outside of a drum diametric direction R to fix and hold the bead ring 9 to a recessed bead housing part 11. The winding accelerating means 8 arranged outside the width direction of the bead lock 7 is moved to the outside of the drum diametric direction R to raise the rubber reinforcing member 5 together with the bladder 2 to the outside of the drum diametric direction R. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a manufacturing apparatus and a manufacturing method for a pneumatic tire, and more particularly to a manufacturing apparatus and a manufacturing method for a pneumatic tire having a structure in which a carcass band is wound around a bead ring, and in particular, a bead ring in such a pneumatic tire. This prevents the occurrence of poor winding of the carcass band.

  In pneumatic tires, especially heavy duty tires such as trucks and buses, at least one carcass ply extends in a toroidal shape between a pair of bead parts in which bead rings are embedded, and the end of the carcass ply is beaded. In general, a structure in which the carcass ply is prevented from being pulled out while rolling around the tire by rolling back around the tire from the inner side to the outer side in the tire width direction. However, in such a conventional pneumatic tire, it is necessary to sufficiently increase the rewinding height of the carcass ply in order to enhance the carcass ply pull-out prevention effect and improve the durability of the bead part. However, since this structure also causes a rigid step at the inner and outer sides in the tire radial direction at the end of the carcass ply at the same time, stress tends to concentrate near the end of the carcass ply due to tire rolling. There was a problem that cracks occurred from here and the durability of the bead portion was lowered.

  Conventionally, it has been attempted to prevent the occurrence of cracks by improving the bead structure for such problems. For example, Patent Documents 1 and 2 disclose in advance at least one end region of a cylindrical carcass band in advance. There is described a pneumatic tire in which a bent portion is formed by applying outward crease, a bead ring is disposed inside the bent portion, and the bead ring is surrounded by an end portion of the carcass band. This bead part structure has the end of the carcass band wound around the bead ring, so it can suppress the concentration of stress on the end of the carcass band, preventing the occurrence of cracks and improving the durability of the bead part. it can. In the production of a pneumatic tire having such a bead portion structure, when forming a raw tire, the bead ring is set at a predetermined position in a state where the bent portion is elastically deformed outward in the width direction by a bead setter, and is fixedly held by a bead lock. Thereafter, the carcass band is wound around the bead ring by removing the bead setter and restoring the bent portion by the action of repulsive force.

  However, the green tire is usually molded on a molding drum having a bladder, and a wire chafer or a rubber chafer may be attached to the inner surface of the end portion of the carcass band. As shown in FIG. 5B, the bead setter 102 holding the bead ring 101 is moved outward in the width direction of the drum to press the bending portion 103 outward in the width direction of the drum to be elastically deformed. When the bead ring 101 is fixed at a predetermined position by the bead lock 104 having both ends of the shape and the concave bead storage portion, the lower portion 105 of the bent portion 103 is brought into close contact with the bladder 106 and the rubber chafer, as shown in FIG. As shown in Fig. 2, even after removing the bead setter, the tightly attached bladder and rubber chafer prevent the folded part from being restored. Ri bending portion can not be completely restored to the original shape, it may not be possible to sufficiently surround the bead ring. When a product tire is manufactured from a raw tire in such a state, the end portion of the carcass band is likely to be detached from the bead ring during load rolling, which may cause a failure of the bead portion.

JP 2000-225653 A JP 2001-252991 A

  Accordingly, an object of the present invention is to provide a pneumatic tire manufacturing apparatus and manufacturing method capable of reliably winding a rubber reinforcing member including a carcass band having a bent portion around a bead ring and exhibiting high bead portion durability. Is to provide.

  In order to achieve the above object, a pneumatic tire manufacturing apparatus according to the present invention forms a rubber reinforcing member including a cylindrical carcass band by wrapping a cord rubberized sheet having bent portions bent outward at both sides. In order to achieve this, with the molding drum having an expandable bladder in the center of the width and the bead ring being separably held, it is moved outwardly in the drum width direction while being in contact with the bending portion of the carcass band, so that the bending portion is elastic. A bead setter that sets the bead ring at a predetermined position on the carcass band while being deformed, a convex bead storage portion that is positioned between the both ends of the convex shape, and the bead ring that is set at the predetermined position has a drum diameter A bead lock that expands from the inner side in the direction and is fixed and held in the bead storage part, and a bead in a state where the bead ring is fixed and held Tsu is the machining portion bent lifting the drum radially outward with bladder rubber reinforcing member positioned in the width direction outer end portion on the click that comprises a winding promoting means for securely wrapped against the bead ring. According to this apparatus, even when the bent portion elastically deformed outward in the width direction by the bead setter comes into close contact with the bladder or the rubber chafer, the winding promoting means assists the restoration of the bent portion, As a result, the end of the carcass band can be removed from the bead portion during load rolling in the product tire, and high bead portion durability can be obtained. it can.

  In this device, the winding promoting means is a plate that moves outward in the radial direction of the drum along the side surface thereof toward the outer end portion in the width direction of the bead lock, or the outer end portion in the width direction of the bead lock. It can be a roll that rolls on the side.

  Further, it is preferable that the winding promoting means has a lifting amount for lifting the bladder outward in the drum radial direction within a range of 10 to 50 mm. If the lifting amount is less than 10 mm, the effect of promoting the winding by assisting the restoration of the bent portion may be insufficient, and if it exceeds 50 mm, the bent portion exceeds the original shape and extends inward in the width direction. This is because it may be deformed.

  And the manufacturing method of the pneumatic tire according to the present invention includes a rubber reinforcing member including a cylindrical carcass band having a bent portion on both sides on a molding drum having an inflatable bladder at the center of the width. Prepared and moved the bead setter with the bead ring separable to the outside of the drum width direction while abutting on the bending portion of the carcass band, and elastically deforming the bending portion, while the bead ring is fixed on the carcass band. The bead lock, which has a bead lock set at a predetermined position, is expanded from the inner side in the drum radial direction, and the bead ring set at a predetermined position is placed in the bead storage unit. The bead setter is held in the bent portion while maintaining the state in which the bead setter is held in contact with the bent portion. Move to the radially outer position of the bead ring just before the position where it winds around the bead ring, activate the winding facilitating means, and position it on the outer end in the width direction of the bead lock with the bead ring fixed and held The part of the rubber reinforcing member to be lifted together with the bladder is moved outward in the drum radial direction, and the bead setter is moved to release the contact state with the bent portion, thereby restoring the bent portion and winding it securely around the bead ring. It has a manufacturing process for raw tires. According to this manufacturing method, even when the bent portion elastically deformed outward in the width direction by the bead setter is in close contact with the bladder or the rubber chafer, the winding promoting means assists the restoration of the bent portion. As a result of being able to wind with the bead ring completely stored in the part, there is no possibility that the end of the carcass band will come off from the bead part during load rolling in the product tire, and high bead part durability is obtained. Can do.

  In this method, the winding promoting means is a plate that moves outward in the radial direction of the drum along its side surface toward the outer end in the width direction of the bead lock, or the outer end in the width direction of the bead lock. It can be a roll that rolls on the side.

  Furthermore, in this method, the bent portion of the carcass band can be formed on the molding drum, but the carcass band in which the bent portion is formed in advance can also be supplied onto the molding drum.

  According to the present invention, there is provided a manufacturing apparatus and a manufacturing method for a pneumatic tire capable of reliably winding a rubber reinforcing member including a carcass band having a bent portion around a bead ring and exhibiting high bead portion durability. It becomes possible to do.

  Embodiments of the present invention will be described below with reference to the drawings. 1A to 1C are cross-sectional views in the width direction of the main part of a typical pneumatic tire manufacturing apparatus according to the present invention. As shown to Fig.1 (a), the manufacturing apparatus 1 is equipped with the shaping | molding drum 3 which has the bladder 2 which can expand | swell in the width center. As shown in FIG. 1B, the molding drum 3 is wound with a cord rubberized sheet having bent portions 4 that are bent outward, on both sides, and a rubber reinforcing member 5 including a cylindrical carcass band. It is formed. In addition, in FIG.1 (b), although the bending process part 4 showed the rubber reinforcement member which has three bending parts, a bending part may be one place, two places, or four or more places. The manufacturing apparatus 1 further includes a bead setter 6, a bead lock 7, and winding promoting means 8. The bead setter 6 can hold the bead ring 9 in a separable manner, is movable in both the drum width direction W and the radial direction R, and is in contact with the bending portion 4 of the carcass band while being outside the drum width direction W. The bead ring 9 can be set at a predetermined position on the carcass band while being bent and elastically deforming the bent portion 4. As shown in FIG. 2, the bead lock 7 has convex end portions 10 and a concave bead storage portion 11 that is located between the both end portions 10 and conforms to the shape of the bead ring 9. The bead ring 9 can be fixedly held in the bead storage portion 11 by moving outward in the direction R. The winding promoting means 8 is disposed on the outer side in the width direction of the bead lock 7, and can move to the outer side in the drum radial direction R to lift the rubber reinforcing member 5 together with the bladder 2 to the outer side in the drum radial direction R.

  Although not shown, the manufacturing apparatus 1 has a driving means for rotating the molding drum 3, a servicer for supplying the cord rubberized sheet, and an O-ring that holds the supplied rubberized sheet until joining. Needless to say, it includes components required for a normal raw tire molding apparatus.

  Next, a method for manufacturing a raw tire using the manufacturing apparatus 1 configured as described above will be described. First, on the molding drum 3, a rubber reinforcing member 5 including a cylindrical carcass band having a bent portion 4 that is bent outward is provided on both sides. Then, for example, the bead setter 6 holding the bead ring 9 in a separable manner by magnetic attraction is moved toward the outer side in the width direction of the molding drum 3, and as shown in FIG. Make contact. In this state, the bead setter 6 is further moved outward in the width direction, and when the bead ring 9 is restored to a predetermined position on the carcass band, preferably the folding processing unit 4 as shown in FIG. The bent portion 4 of the carcass band is pressed outward in the drum width direction until it reaches a position where the bent portion 4 and the apex of the bead ring 9 substantially coincide with each other to be elastically deformed. Next, after separating the bead ring 9 from the bead setter 6, the bead lock 7 is expanded from the inner side in the drum radial direction, and the bead set at a predetermined position with the rubber reinforcing member 5 interposed therebetween as shown in FIG. The ring 9 is fixedly held in the bead storage part 11. At this time, the bending-processed portion 4 that has been elastically deformed and the bladder 2 pushed outward in the radial direction by both end portions 10 of the bead lock 7 are brought into close contact with each other. Even if the bead setter 6 is retracted in this state, the restoration of the bent portion 4 may be hindered and a winding failure may occur. Therefore, in the present invention, as shown in FIG. 3 (d), the bead setter 6 is connected to the bead ring 9 with the bead setter 6 being kept in a state where the bead setter 6 is in contact with the bent portion 6. Move to the radially outward position of the bead ring 9 in front of the wrapping position and operate the wrapping promoting means 8 to be positioned on the outer end in the width direction of the bead lock 7 with the bead ring 9 fixed and held. When the rubber reinforcing member 5 to be lifted together with the bladder 2 is lifted outward in the drum radial direction, and the bead setter 6 is moved radially outward to release the contact state with the bent portion 4, as shown in FIG. The bent portion 4 is restored by the elastic force and can be reliably wound around the bead ring 9.

  After the series of operations as described above is completed, the process proceeds according to the conventional general manufacturing method until the end of the molding of the raw tire. When the green tire thus obtained is vulcanized, a product tire having particularly excellent bead portion durability can be obtained.

  3 (a) to 3 (e), the winding promoting means 8 is a plate that moves outward in the drum radial direction along the side surface toward the outer end in the width direction of the bead lock 7. For example, as shown in FIGS. 4A and 4B, the bead lock 7 has an outer surface in the width direction that is gently curved toward the inner side in the radial direction, and the winding promoting means is the outer side in the radial direction of the bead lock. It is good also as the roll 12 which rolls on the outer surface toward it. In this case, for example, the rubber reinforcing member 5 positioned on the outer end in the width direction of the bead lock 7 in a state where the roll 12 is driven by the air cylinder 13 and the bead ring 9 is fixedly held is moved together with the bladder 2 in the drum radial direction outer side. Lift to. After that, if the bead setter 6 is retracted, the bent portion 4 can be reliably wound around the bead ring 9 as in the case where the plate-like winding promoting means is used.

  The rubber reinforcing member 5 is formed by winding an inner liner, a chafer or the like supplied from a servicer around a molding drum, and then supplying a flat cord rubberized sheet that is also used for manufacturing a normal pneumatic tire. Bending may be performed on the drum. Alternatively, a cord rubberized sheet may be supplied to the molding drum in a state in which bent portions that are bent outward are formed in advance on both sides thereof.

  As is apparent from the above description, according to the present invention, when the rubber reinforcing member including the carcass band having the bent portion is wound around the bead ring, the bent portion that has been elastically deformed by the bead setter is completely restored. It has become possible to provide a pneumatic tire manufacturing apparatus and manufacturing method capable of reliably winding a rubber reinforcing member around a bead ring and exhibiting high bead durability.

(A) And (b) is width direction sectional drawing of the principal part of the manufacturing apparatus of the typical pneumatic tire according to this invention. It is an expanded sectional view of the principal part of the bead lock shown in FIG. (A)-(e) is process drawing which sets a bead ring in a bending process part according to this invention. (A) And (b) is the schematic of the winding promotion means of the other manufacturing apparatus according to this invention. (A)-(c) is process drawing which sets a bead ring in a bending process part according to the conventional manufacturing method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Pneumatic tire manufacturing apparatus 2 Bladder 3 Molding drum 4 Bending process part 5 Rubber reinforcement member 6 Bead setter 7 Bead lock 8 Winding promotion means 9 Bead ring 10 Both ends of bead setter 11 Bead storage part of bead setter 12 Roll 13 Air cylinder

Claims (9)

  A bead ring is separated from a forming drum having an expandable bladder in the center of the width in order to form a rubber reinforcing member including a cylindrical carcass band by wrapping a cord rubberized sheet having bent portions bent outward on both sides. A bead setter that sets the bead ring at a predetermined position on the carcass band while elastically deforming the bent portion by moving it outward in the drum width direction while being in contact with the bent portion of the carcass band, A bead lock having a concave bead storage portion positioned between the two end portions and a bead lock that is fixedly held in the bead storage portion by expanding the bead ring set in a predetermined position from the inside in the drum radial direction. A rubber reinforcement member located on the outer edge in the width direction of the bead lock with the ring fixed and held together with the bladder and the drum diameter Apparatus for manufacturing a pneumatic tire according to comprises a winding promoting means for securely wrapped against the bead ring machining portion bent lifting direction outwardly.   2. The pneumatic tire manufacturing apparatus according to claim 1, wherein the winding accelerating means is a plate that moves outward in the drum radial direction along a side surface of the bead lock toward the outer end in the width direction.   The said winding promotion means is a manufacturing apparatus of the pneumatic tire of Claim 1 which is a roll which rolls on the side surface toward the width direction outer end part of a bead lock.   The said winding promotion means is a manufacturing apparatus of the pneumatic tire as described in any one of Claims 1-3 which makes the lifting amount which lifts a bladder to the drum radial direction outer side the range of 10-50 mm. Prepare a rubber reinforcing member including a cylindrical carcass band having bent portions on both sides on a molding drum having an expandable bladder in the width center,
The bead setter holding the bead ring in a separable manner is moved outward in the drum width direction while abutting against the bent portion of the carcass band, and the bead ring is set at a predetermined position on the carcass band while elastically deforming the bent portion. And
The bead lock having a convex bead storage portion and a concave bead storage portion positioned between the both end portions is expanded from the inside in the drum radial direction, and the bead ring set at a predetermined position is fixedly held in the bead storage portion,
While maintaining the bead setter in contact with the bent portion, the bead setter is moved to the radially outer position of the bead ring before the position where the end of the bent portion is wrapped around the bead ring,
By operating the winding promoting means, the part of the rubber reinforcing member located on the outer end in the width direction of the bead lock in a state where the bead ring is fixed and held is lifted together with the bladder to the outside in the drum radial direction,
A pneumatic tire manufacturing process comprising: a raw tire manufacturing process in which a bead setter is moved to release a contact state with a bent portion, whereby the bent portion is restored and the bead ring is securely wound around the bead ring. Production method.   The method of manufacturing a pneumatic tire according to claim 5, wherein the winding promoting means is a plate that moves outward in the drum radial direction along a side surface thereof toward an outer end portion in the width direction of the bead lock.   The said winding promotion means is a manufacturing method of the pneumatic tire of Claim 5 which is a roll which rolls on the side surface toward the width direction outer end part of a bead lock.   The manufacturing method of the pneumatic tire as described in any one of Claims 5-7 which forms the bending process part of a carcass band on a shaping | molding drum.   The manufacturing method of the pneumatic tire as described in any one of Claims 5-7 which supplies the carcass band which formed the bending process part previously on a shaping | molding drum.

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