JP2020023152A - Method and apparatus for manufacturing pneumatic tire with sealant - Google Patents

Abstract

To form a high quality sealant layer with less thickness variation.SOLUTION: A method for manufacturing a pneumatic tire with sealant includes an adhesion step K1 and a pressing step K2. In the adhesion step K1, the method allows a string-shaped sealant 16 discharged from a nozzle 15 to adhere to a tire inner circumferential surface S while spirally winding the sealant. In the pressing step K2, during the time when a next string-shaped sealant 16 is adhered to an adjacent position to the adhered string-shaped sealant 16, the adhered string-shaped sealant 16 is pressed to the tire inner circumferential surface S.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a method and an apparatus for manufacturing a pneumatic tire with a sealant capable of forming a high-quality sealant layer for preventing puncture on the inner peripheral surface of the tire.

  For example, in Patent Document 1 below, as shown in FIG. 11 (a), a string-like sealant c discharged from a nozzle b is adhered to a tire inner peripheral surface a while spirally winding the sealant layer c, thereby forming a layer of the sealant. It is proposed to form.

JP-A-2017-178310

  In such a forming method, when the height h from the tire inner peripheral surface a to the tip of the nozzle b is large, the string-shaped sealant c contacts the tire inner peripheral surface a only by its own weight. For this reason, the adhesion of the string-shaped sealant c becomes insufficient and the position is shifted, which causes a problem that a gap is formed between the adjacent string-shaped sealants c and c, or that the string-shaped sealant c runs on the adjacent string-shaped sealant c. Also, a part of the sealant layer may be peeled off.

  Therefore, in practice, as shown in FIGS. 11B and 11C, the nozzle b is brought close to the tire inner peripheral surface a, and the string-shaped sealant is started from a height h smaller than the thickness t of the layer of the sealant c. c is being discharged. Thereby, the adhesive force can be increased by the action of the discharge pressure.

  However, the inner circumferential surface a of the tire fluctuates up and down due to variations in the tread thickness of the tire, vibration during rotation of the tire, and the like. Therefore, when h <t, the thickness t of the sealant layer becomes non-uniform, and the nozzle b tends to rub against the inner peripheral surface a of the tire to cause a bald portion.

  The present invention can apply a string-shaped sealant with a high adhesive force even when the height from the tire inner peripheral surface to the nozzle tip is larger than the thickness of the sealant layer, and has a high quality with less thickness variation. An object of the present invention is to provide a method and an apparatus for manufacturing a pneumatic tire with a sealant capable of forming a sealant layer.

The present invention is a method for manufacturing a pneumatic tire with a sealant having a sealant layer for preventing puncture on the inner peripheral surface of the tire,
On the inner circumferential surface of the tire, an adhesive step of spirally adhering the string-shaped sealant discharged from the nozzle while spirally winding,
Pressing the sticky string sealant against the inner circumferential surface of the tire until the next string sealant is stuck next to the sticky string sealant.

  In the method of manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that in the pressing step, the sticky string-shaped sealant is pressed against the inner peripheral surface of the tire by a roller.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, in the pressing step, the position at which the string-like sealant is pressed by the roller and the string-like sealant discharged from the nozzle start contacting the tire inner peripheral surface. It is preferable that a circumferential distance L along the inner circumferential surface of the tire from the position is 100 mm or less.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, it is also preferable that in the pressing step, the adhesive string-like sealant is pressed against the inner peripheral surface of the tire by wind pressure.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that the wind pressure is based on ejection of compressed air from an air nozzle.

  In the method of manufacturing a pneumatic tire with a sealant according to the present invention, in the pressing step, the center position of pressing the string-shaped sealant by the wind pressure and the string-shaped sealant discharged from the nozzle start contacting the tire inner peripheral surface. It is preferable that a circumferential distance L along the inner circumferential surface of the tire between the position and the position at which the tire runs is 50 mm or less.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, the pressing step includes a step of: controlling a wind pressure of the compressed air from the air nozzle and one or more auxiliary airs disposed on a rear side in a winding direction of the air nozzle. It is preferable that the adhered string-like sealant is pressed against the inner peripheral surface of the tire by wind pressure of compressed air from a nozzle.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that the ejection port of the air nozzle has a circular shape and an inner diameter of 0.5 to 3.0 mm.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that the ejection port of the air nozzle is movable in the tire axial direction with respect to the nozzle.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, the air nozzle includes a plurality of ejection ports arranged in the tire axial direction, and compressed air is switched from one of the plurality of ejection ports to eject compressed air. Preferably.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that a height in a tire radial direction from an outlet of the air nozzle to an inner peripheral surface of the tire be adjustable.

The present invention is an apparatus for manufacturing a pneumatic tire with a sealant having a sealant layer for preventing puncture on the inner peripheral surface of the tire,
A tire support that rotatably supports the tire in an upright state,
On the tire inner peripheral surface of the rotatably supported tire, an adhesive means to adhere while spirally winding a string-shaped sealant,
Pressing means for pressing the sticky string sealant against the inner peripheral surface of the tire until the next string sealant is stuck next to the sticky string sealant.

  In the apparatus for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that the adhesive unit includes a nozzle that discharges the string-shaped sealant toward the inner peripheral surface of the tire.

  In the apparatus for manufacturing a pneumatic tire with a sealant according to the present invention, the pressing means preferably includes a roller for pressing the string-shaped sealant against the inner peripheral surface of the tire.

  In the apparatus for manufacturing a pneumatic tire with a sealant according to the present invention, the pressing means preferably includes an air nozzle for pressing the string-shaped sealant against the inner peripheral surface of the tire by jetting compressed air.

  In the method for manufacturing a pneumatic tire with a sealant according to the present invention, the pressing means includes the air nozzle and one or more auxiliary air nozzles disposed on a rear side in a winding direction of the air nozzle. preferable.

  In the apparatus for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that the pressing means be capable of moving an ejection port of the air nozzle in a tire axial direction with respect to the nozzle.

  In the apparatus for manufacturing a pneumatic tire with a sealant according to the present invention, the air nozzle includes a plurality of ejection ports arranged in the tire axial direction, and the pressing means is configured to supply compressed air from one of the plurality of ejection ports. It is preferred to switch and eject.

  In the apparatus for manufacturing a pneumatic tire with a sealant according to the present invention, it is preferable that the pressing means is capable of adjusting a height in a tire radial direction from an outlet of the air nozzle to an inner peripheral surface of the tire.

  In the manufacturing method of the present invention, as described above, a pressing step of pressing the sticky string sealant against the tire inner peripheral surface until the next string sealant is stuck next to the sticky string sealant. including.

  Therefore, even when the height from the tire inner peripheral surface to the nozzle tip is larger than the thickness of the sealant layer, the string-like sealant can be stuck to the tire inner peripheral surface with high adhesive strength. Therefore, it is possible to prevent a part of the sealant layer from being peeled off, a gap from being formed between adjacent string-shaped sealants, or being able to run on the adjacent string-shaped sealant due to insufficient adhesive force. Further, since it is hard to be affected by the variation in the tread thickness and the vibration during the rotation of the tire, the variation in the thickness of the sealant layer can be suppressed. Therefore, a high quality sealant layer can be efficiently formed.

  As described above, the manufacturing apparatus of the present invention also includes the tire support, the adhesive means, and the pressing means, so that the same effects as those of the manufacturing method can be obtained.

It is a meridional sectional view showing an adhesion process in a manufacturing method of a pneumatic tire with a sealant of the present invention. It is a sectional view of a peripheral direction showing a pressing process using a roller. It is the key map which looked at an adhesion process and a pressing process from the tire radial direction inside. It is sectional drawing of a roller. It is a sectional view of a peripheral direction showing a pressing process using wind pressure. (A)-(d) is a conceptual diagram which shows the opening shape of the ejection opening of an air nozzle. (A)-(d) is a conceptual diagram which shows the arrangement of the air nozzle and the auxiliary air nozzle in an Example. It is a meridional sectional view of a tire formed by a manufacturing method of a pneumatic tire with a sealant of the present invention. (A), (b) is sectional drawing explaining the positional shift of the center line of a nozzle, and the part of the string-shaped sealant adhered to the tire inner peripheral surface. (A)-(c) is sectional drawing which shows the other example of the pressing means using the air nozzle. (A)-(c) is sectional drawing which shows the conventional method of forming the layer of a sealant.

Hereinafter, embodiments of the present invention will be described in detail.
FIG. 8 is a meridional cross-sectional view of the pneumatic tire 1 with a sealant formed by the manufacturing method of the present invention. The pneumatic tire 1 with a sealant of the present embodiment includes a tire 1A and a puncture-preventing sealant layer 10 disposed on a tire inner peripheral surface S of the tire 1A.

  The tire 1A is a tubeless tire, and in this example, a carcass 6 extending from the tread portion 2 to the bead core 5 of the bead portion 4 through the sidewall portion 3 and a radially outer side of the carcass 6 and inside the tread portion 2 It further includes a belt layer 7 disposed and an inner liner layer 9 disposed radially inside the carcass 6.

  The carcass 6 is formed from one or more (one in this example) carcass plies 6A having carcass cords arranged at an angle of, for example, 75 to 90 ° with respect to the tire circumferential direction. The carcass ply 6A includes, at both ends of a ply body 6a extending between the bead cores 5, 5, a ply turn-up portion 6b formed by turning the bead core 5 from the inside in the tire axial direction to the outside.

  The belt layer 7 is formed from a plurality (for example, two) of belt plies 7A and 7B having belt cords arranged at an angle of, for example, 10 to 40 degrees with respect to the tire circumferential direction. The belt plies 7A and 7B are stacked with different inclination directions so that the belt cords intersect between the plies. For the purpose of enhancing the high-speed durability of the tire, a band layer (not shown) having a band cord wound spirally may be provided radially outside the belt layer 7.

  The inner liner layer 9 is made of an air-impermeable rubber such as butyl rubber, and keeps the tire pressure airtight. The inner peripheral surface of the inner liner layer 9 constitutes the tire inner peripheral surface S.

  Then, the sealant layer 10 is disposed on the inner peripheral surface S of the tire, particularly on the inner peripheral surface 2S of the tread portion 2. The width W of the sealant layer 10 is preferably 85 to 115% of the maximum width WB of the belt layer, because the puncture prevention performance is more suitably obtained. The thickness t of the sealant layer 10 is preferably 1 to 10 mm, and if it is less than 1 mm, it is difficult to reliably close the puncture hole. Conversely, if it exceeds 10 mm, the effect of closing the puncture hole saturates, and rather causes a disadvantage of increasing the weight of the tire.

  The sealant for forming the sealant layer 10 is not particularly limited, but the one described in Patent Document 1 is suitably used. Specifically, the sealant of the present example contains a rubber component, a liquid polymer, and a crosslinking agent.

  As the rubber component, butyl rubber such as butyl rubber and halogenated butyl rubber is used. As the rubber component, the butyl rubber and a diene rubber can be mixed, but from the viewpoint of fluidity and the like, the content of the butyl rubber in 100 parts by mass of the rubber component is preferably 90 parts by mass or more. preferable.

  Examples of the liquid polymer include liquid polybutene, liquid polyisobutene, liquid polyisoprene, liquid polybutadiene, liquid poly α-olefin, liquid isobutylene, liquid ethylene α-olefin copolymer, liquid ethylene propylene copolymer, liquid ethylene butylene copolymer, and the like. No. Among them, liquid polybutene having a number average molecular weight of 1,000 to 4,000 is preferred from the viewpoint of imparting tackiness and the like.

  The content of the liquid polymer is preferably at least 50 parts by mass, more preferably at least 100 parts by mass, based on 100 parts by mass of the rubber component. If the amount is less than 50 parts by mass, the adhesiveness may be reduced. The upper limit of the content is preferably 400 parts by mass or less, more preferably 300 parts by mass or less. If the amount exceeds 400 parts by mass, the sealant material may flow during traveling.

  Known compounds can be used as the crosslinking agent, but organic peroxides are preferred. Adhesiveness, sealability, fluidity, and processability are improved by using a butyl rubber or a liquid polymer in the organic peroxide crosslinking system.

  Examples of the organic peroxide (crosslinking agent) include acyl peroxides such as benzoyl peroxide, dibenzoyl peroxide, and p-chlorobenzoyl peroxide, 1-butylperoxyacetate, t-butylperoxybenzoate, and t-butylperoxybenzoate. Peroxyesters such as -butylperoxyphthalate; ketone peroxides such as methyl ethyl ketone peroxide; alkyl peroxides such as di-t-butylperoxybenzoate and 1,3-bis (1-butylperoxyisopropyl) benzene , Hydroperoxides such as t-butyl hydroperoxide, dicumyl peroxide, t-butyl cumyl peroxide and the like. Among them, acyl peroxides are preferred, and dibenzoyl peroxide is particularly preferred, from the viewpoint of adhesiveness and fluidity.

  The content of the organic peroxide (crosslinking agent) is preferably at least 0.5 part by mass, more preferably at least 1.0 part by mass based on 100 parts by mass of the rubber component. If the amount is less than 0.5 parts by mass, the crosslink density may be low, and the sealant material may flow. The upper limit of the content is preferably 40 parts by mass or less, more preferably 20 parts by mass or less. If the amount exceeds 40 parts by mass, the crosslink density may increase, and the sealing property may decrease.

  A crosslinking aid (vulcanization accelerator), an inorganic filler, a plasticizer, and the like can be appropriately added to the sealant material.

  Examples of the crosslinking assistant (vulcanization accelerator) include sulfenamide, thiazole, thiuram, thiourea, guanidine, dithiocarbamine, aldehyde-amine, aldehyde-ammonia, imidazoline, xanthate, And quinone dioxime compounds (quinoid compounds). The compounding amount of the crosslinking assistant (vulcanization accelerator) is preferably 1 to 15 parts by mass with respect to 100 parts by mass of the rubber component.

  The inorganic filler can be selected from the group consisting of carbon black, silica, calcium carbonate, calcium silicate, magnesium oxide, aluminum oxide, barium sulfate, talc, mica and the like. The amount of the inorganic filler is preferably 1 to 30 parts by mass with respect to 100 parts by mass of the rubber component.

  The plasticizer can be selected from the group consisting of aromatic process oils, naphthenic process oils, paraffinic process oils, and the like. The amount of the plasticizer is preferably 1 to 40 parts by mass with respect to 100 parts by mass of the rubber component.

  In particular, in the sealant, by using a mixture of butyl rubber as the rubber component and liquid polybutene and liquid polyisobutene as the liquid polymer, the adhesiveness, the sealability, the fluidity, and the processability are preferably improved in a well-balanced manner. . At this time, the content of the liquid polymer is preferably in the range of 100 to 400 parts by mass, and the content of the organic peroxide (crosslinking agent) is in the range of 1 to 15 parts by mass with respect to 100 parts by mass of the butyl rubber. Is preferred. The crosslinking aid (vulcanization accelerator) is preferably contained in an amount of 1 to 15 parts by mass based on 100 parts by mass of the butyl rubber, and the inorganic filler is contained in an amount of 1 to 30 parts by mass based on 100 parts by mass of the butyl rubber. It is preferably contained in parts by mass.

  Note that a sound damper (not shown) made of a sponge material extending in the tire circumferential direction may be formed on the inner peripheral surface of the sealant layer 10. The width of the sound damping body is preferably 50 to 95% of the width W of the sealant layer 10.

  Next, the manufacturing method of the pneumatic tire 1 with a sealant includes a layer forming step of forming a layer 10 of the sealant on the tire inner peripheral surface S of the tire 1A that has been vulcanized and formed in advance. The layer forming step includes an adhesive process K1 (shown in FIG. 1) and a pressing process K2 (shown in FIG. 2).

  As shown in FIGS. 1 and 2, in the adhesion step K <b> 1, the string-shaped sealant 16 discharged from the nozzle 15 is adhered to the tire inner peripheral surface S while being spirally wound.

  Specifically, the string-shaped sealant 16 is turned downward from the tip of the nozzle 15 toward the tire inner peripheral surface S of the tire 1A in the upright state, which moves laterally at a constant speed to one side in the tire axial direction while rotating at a constant speed. Discharge. Thereby, the string-shaped sealant 16 can be spirally adhered to the tire inner peripheral surface S.

  Reference numeral 30 in the drawing denotes a pair of horizontal tire holding rollers that can be driven to rotate. The tire 1A can be rotated at a constant speed around the tire axis j1 by holding and holding the tire 1A between the tire holding rollers 30, 30. Reference numeral 31 denotes a support for the tire holding roller 30, and the tire 1A can move laterally at a constant speed in the tire axial direction together with the tire holding roller 30.

  A continuous kneader (not shown) such as a twin-screw kneading extruder is connected to the nozzle 15, and a sealant in which a material including a rubber component, a liquid polymer, and a crosslinking agent is kneaded is supplied from the continuous kneader to the nozzle 15 at a constant speed. Supplied with.

  In the adhesion step K1, the radial height h from the tire inner circumferential surface S to the tip of the nozzle 15 is larger than the thickness t of the sealant layer 10. For this reason, the string-shaped sealant 16 can be adhered to the tire inner peripheral surface S without being affected by variations in the tread thickness T, vibration during rotation of the tire, and the like.

  In the pressing step K2, the sticky string sealant 16 is pressed against the tire inner peripheral surface S until the next string sealant is stuck next to the sticky string sealant 16. Thereby, adhesion of the string-shaped sealant 16 to the tire inner peripheral surface S is assisted, and displacement of the string-shaped sealant 16 due to poor adhesion is prevented.

  In this example, the case of the first embodiment in which the string-shaped sealant 16 is pressed against the tire inner peripheral surface S by the roller 17 is shown.

  The roller 17 is rotatably supported on the rod end of the cylinder 18 via a roller holder in the tire circumferential direction, for example. The cylinder 18 is attached to a support 19 that supports the nozzle 15, for example. In this example, the cylinder 18 expands and contracts along the radial line 25 extending from the tire axis j1, and the roller 17 presses the string-like sealant 16 against the tire inner peripheral surface S by extension.

  In the pressing step K2, the inner circumferential surface of the tire between the position Pa at which the string-like sealant 16 is pressed by the roller 17 and the position Pb at which the string-like sealant 16 discharged from the nozzle 15 starts to contact the inner circumferential surface S of the tire. The circumferential distance L along S is preferably 100 mm or less. Strictly, the “position Pa” means a position where a radial line X1 passing through the tire axis j1 and the center j2 of the roller 17 intersects the tire inner peripheral surface S.

  Between the position Pb and the position Pa, the adhesion of the string-like sealant 16 is weak. Therefore, if the circumferential distance L exceeds 100 mm, there is a high risk that the string-shaped sealant 16 will be displaced up to the position Pa. Therefore, the upper limit of the circumferential distance L is more preferably 50 mm or less. In the embodiment of Table 1 described later, the position where the center line Pc of the nozzle 15 intersects the tire inner peripheral surface S is substantially equal to the position Pb.

  Since the sealant has a high adhesive force, the sealant sticks to the roller 17 with a normal metal roller, rubber roller, or the like, and hinders formation of the sealant layer 10. Therefore, as shown in FIG. 4, it is preferable to form a surface layer 17A made of a non-adhesive resin such as a silicon-based resin, a fluorine-based resin, or a siloxane-based resin on the surface of the roller 17.

  FIG. 5 shows a second embodiment of a pressing step of pressing the string-shaped sealant 16 against the tire inner peripheral surface S by wind pressure. The wind pressure can be generated by the ejection of the compressed air 21 from the air nozzle 20.

  In the second embodiment, the inner circumference of the tire between the center position Qa at which the string sealant 16 is pressed by the wind pressure and the position Qb at which the string sealant 16 discharged from the nozzle 15 starts contacting the inner circumferential surface S of the tire. Preferably, the circumferential distance L along the surface S is 50 mm or less. Strictly, the “center position Qa” means a position where the center line X2 in the direction in which the compressed air 21 is ejected from the air nozzle 20 intersects the tire inner peripheral surface S.

  In the second embodiment, it is easy to bring the air nozzle 20 closer to the nozzle 15. Therefore, the circumferential distance L is preferably set to 50 mm or less from the viewpoint of reducing the risk of the string sealant 16 being displaced.

  The air outlet 20H of the air nozzle 20 is preferably circular as shown in FIG. 6B, and the inner diameter D of the air outlet 20H is preferably in the range of 0.5 to 3.0 mm. When the inner diameter D is less than 0.5 mm, the wind pressure acts locally, so that the string-like sealant 16 is torn and the force for pressing the string-like sealant 16 is weakened. On the other hand, when the inner diameter D exceeds 3.0 mm, wind enters between the string-shaped sealant 16 and the tire inner peripheral surface S, and the attached string-shaped sealant 16 tends to float.

  As shown in FIGS. 6A and 6C, as the ejection port 20H, in addition to the circular shape, a rectangular shape (including a square) and an elliptical shape (including an oblong shape) can be adopted. As shown in FIG. 6D, the ejection port 20H may be formed by a plurality of small holes 22. In this case, the plurality of small holes 22 are preferably arranged in the tire circumferential direction.

  As shown in FIGS. 7B to 7D, in the pressing step K2, the wind pressure of the compressed air from the air nozzle 20 and one or more auxiliary It is also preferable that the string-shaped sealant 16 is pressed against the tire inner peripheral surface S by the wind pressure of the compressed air from the air nozzle 23. Thereby, the string-like sealant 16 can be bonded more reliably. When the number of auxiliary air nozzles 23 is two or more, the bonding effect of the string-shaped sealant 16 is saturated. Therefore, one auxiliary air nozzle 23 is preferable.

  Here, as shown in FIGS. 9A and 9B, when forming the sealant layer 10, the nozzle center 15j (corresponding to the discharge direction) of the nozzle 15 and the string-shaped sealant 16 are attached to the inner periphery of the tire. The center 16j of the portion 16A adhered to the surface S tends to cause a positional shift δ in the tire axial direction.

  FIG. 9A shows the initial stage of the formation of the sealant layer 10. The string-like sealant 16 usually starts sticking near the tread edge. However, near the tread edge, the inclination of the tire inner peripheral surface S with respect to the tire axial direction is large, and a displacement δ occurs due to the inclination. I do.

  FIG. 9B shows the case where the formation of the sealant layer 10 is in the middle stage. In the middle stage of formation, the influence of the inclination of the tire inner peripheral surface S is small. However, the portion 16A to be adhered is pressed by the adhesive portion 16B of the string-like sealant 16 that has been previously adhered, and a positional shift δ occurs.

  Therefore, especially when the portion 16A to be adhered is pressed against the tire inner peripheral surface S using the air nozzle 20, the sealant layer 10 may be disturbed due to the positional deviation δ.

  Therefore, as shown in exaggerated manner in FIGS. 10A and 10B, the ejection port 20 </ b> H of the air nozzle 20 is movable in the tire axial direction with respect to the nozzle 15, and the compressed air from the air nozzle 20 is It is preferable to adjust so as to discharge toward the center 16j of the portion 16A to be adhered.

  In FIG. 10A, the air nozzle 20 is supported so as to be tiltable around a fulcrum J. By adjusting the tilt angle, compressed air can be discharged toward the center 16j of the portion 16A to be adhered. In FIG. 10 (b), the air nozzle 20 itself is supported so as to be able to move in parallel in the axial direction of the tire, and compressed air is discharged toward the center 16j of the portion 16A to be adhered by adjusting the moving distance. Can.

  Further, as shown exaggeratedly in FIG. 10 (c), a plurality of ejection ports 20H arranged in the tire axis direction may be provided, and compressed air may be switched and ejected from one of the plurality of ejection ports 20H. preferable. In this example, a case is shown in which a plurality of air nozzles 20 are arranged in parallel in the tire axial direction. However, one air nozzle 20 may be provided with a plurality of switchable ejection ports 20H.

  It is also preferable that the height in the tire radial direction from the ejection port 20H of the air nozzle 20 to the tire inner circumferential surface S be adjustable in order to suppress the disturbance of the sealant layer 10.

  Next, as shown in FIG. 1, the apparatus employed in the pneumatic tire manufacturing method includes a tire support 40 that rotatably supports the tire 1A in an upright state, and a tire 1A that is rotatably supported. Between the string-like sealant 16 and the next string-like sealant 16 next to the sticky string-like sealant 16 being adhered to the tire inner peripheral surface S while spirally winding the string-like sealant 16 on the tire inner peripheral surface S. And pressing means 42 (shown in FIGS. 2 and 5) for pressing the adhered string-shaped sealant 16 against the tire inner peripheral surface S.

  As described above, the tire support 40 of this example includes a pair of horizontally rotatable and drivable tire holding rollers 30, and the tire 1 </ b> A is straddled between the tire holding rollers 30 and held. Thereby, the tire 1A can be rotated at a constant speed around the tire axis j1 in the upright state. The tire support 40 includes a support base 31 that supports the holding roller 30 so as to be able to move laterally at a constant speed in the tire axial direction.

  The adhesive means 41 includes the nozzle 15 for discharging the string-like sealant 16 toward the tire inner peripheral surface S as described above.

  As described above, the pressing means 42 includes the roller 17 for pressing the string-shaped sealant 16 against the tire inner peripheral surface S, or the air nozzle 20 for pressing the string-shaped sealant 16 against the tire inner peripheral surface S by jetting compressed air.

  In the case of forming a sound damper, a sound damper formed in a band shape in advance can be attached to the inner peripheral surface of the sealant layer 10 directly without using an adhesive.

  As described above, particularly preferred embodiments of the present invention have been described in detail. However, the present invention is not limited to the illustrated embodiments, and can be implemented in various forms.

(1)
In order to confirm the effects of the present invention, a pneumatic tire with a sealant (215 / 55R17) was formed based on the specifications in Table 1. The formed sealant layer 10 was visually checked, and the number of places where the sealant layer 10 became thinner per tire and the number of places where the sealant did not adhere to the tire were compared. The lower the number, the better the quality.

In the adhesion step K1, each component having the composition shown in Table 2 was charged into a twin-screw kneading extruder, and kneaded at a barrel temperature of 100 ° C. and 200 rpm to prepare a sealant. The details of each component described in Table 2 are as follows.
Butyl rubber: Butyl 268 (manufactured by ExxonMobil, Mooney viscosity (ML1 + 8 (125 ° C)) = 32)
Liquid polybutene: Nisseki polybutene HV300 (manufactured by JX Nikko Nisseki Energy Co., Ltd., kinematic viscosity at 40 ° C 26000 mm2 / s, kinematic viscosity at 100 ° C 590 mm2 / s, number average molecular weight 1400)
Carbon black: N330 (manufactured by Cabot Japan, HAF grade, DBP oil absorption 102ml / 100g)
Crosslinking agent: BPO (Dibenzoyl peroxide manufactured by NOF Corporation)
Crosslinking aid: Barnock GM (p-benzoquinone dioxime manufactured by Ouchi Shinko Chemical Co., Ltd.)

  In Examples 6 to 22, the ejection port 20H of the air nozzle 20 does not move with respect to the sealant nozzle 15, and the air nozzle 20 does not shift its nozzle center from the nozzle center of the nozzle 15 in the tire axial direction (offset 0 mm). ).

  As shown in Table 1, in the examples, the places where the sealant layer became thinner and the places where the sealant did not adhere were reduced, and it was confirmed that a high quality sealant layer was formed. In Example 18, the inner diameter of the ejection opening of the air nozzle was too small, and a tear was partially generated in the string-shaped sealant.

(2)
In the pressing step K2 using the air nozzle 20, the position where the compressed air is ejected is adjusted in the tire axial direction, and the formation failure of the sealant layer 10 due to the positional deviation δ (shown in FIGS. 9A and 9B). The effect of the reduction was tested. In Example 31, the ejection port 20H of one air nozzle 20 is configured to be movable in the tire axial direction with respect to the sealant nozzle 15, and the ejection position of the compressed air is continuously controlled by the program control according to the displacement δ. Is adjusted. In Example 31, the adjustment is made within ± 2.0 mm in the tire axial direction with respect to the nozzle center 15j of the nozzle 15 (the traveling direction of the nozzle 15 is defined as +).

In Examples 32 to 34, a plurality of air nozzles 20 are arranged in the tire axial direction, and compressed air is switched from one of the plurality of air nozzles 20 to be blown out, and the position shift δ The position of the compressed air ejection is adjusted by switching. In the embodiment 32, the two air nozzles 20 are arranged at positions of -0.5 mm and +1.5 mm with respect to the nozzle center 15j of the nozzle 15. In Example 33, three air nozzles 20 are arranged at positions of −1.0 mm, +0.5 mm, and +2.0 mm with respect to the nozzle center 15 j of the nozzle 15. In the thirty-fourth embodiment, the four air nozzles 20 are arranged at positions of −1.0 mm, 0 mm, +1.0 mm, and +2.0 mm with respect to the nozzle center 15 j of the nozzle 15.

<Defective formation of sealant layer>
Twenty pneumatic tires with a sealant were prepared, the formed sealant layer 10 was visually checked, and the number of tires in which poor adhesion occurred was compared. The lower the number, the better the quality.

  It can be confirmed that by adjusting the position at which the compressed air is injected in the tire axial direction, formation failure of the sealant layer can be reduced.

DESCRIPTION OF SYMBOLS 1 Pneumatic tire with sealant 10 Layer of sealant 15 Nozzle 16 String-like sealant 17 Roller 20 Air nozzle 20H Spout port 21 Compressed air 23 Auxiliary air nozzle 40 Tire support 41 Adhesive means 42 Press means K1 Adhesive step K2 Press step S Tire Inner surface

Claims (19)

A method for manufacturing a pneumatic tire with a sealant having a layer of a sealant for preventing puncture on the tire inner peripheral surface,
On the inner circumferential surface of the tire, an adhesive step of spirally adhering the string-shaped sealant discharged from the nozzle while spirally winding,
A pressing step of pressing the adhered string-shaped sealant against the inner peripheral surface of the tire before the next string-shaped sealant is adhered next to the adhered string-shaped sealant, Production method.   The method for manufacturing a pneumatic tire with a sealant according to claim 1, wherein in the pressing step, the sticky string-shaped sealant is pressed against the inner peripheral surface of the tire by a roller.   The pressing step is between the position where the roller presses the string sealant by the roller and the position where the string sealant discharged from the nozzle starts to contact the tire inner peripheral surface, along the tire inner peripheral surface. The method for producing a pneumatic tire with a sealant according to claim 2, wherein the circumferential distance L is 100 mm or less.   The method for manufacturing a pneumatic tire with a sealant according to claim 1, wherein the pressing step presses the string-shaped sealant adhered to the tire inner peripheral surface by wind pressure.   The method for manufacturing a pneumatic tire with a sealant according to claim 4, wherein the wind pressure is generated by blowing compressed air from an air nozzle.   The pressing step is performed along the inner circumferential surface of the tire between a center position where the string-like sealant is pressed by the wind pressure and a position where the string-like sealant discharged from the nozzle starts to contact the inner circumferential surface of the tire. The method for manufacturing a pneumatic tire with a sealant according to claim 4 or 5, wherein the circumferential distance L is 50 mm or less.   In the pressing step, the pressure is applied by the wind pressure of the compressed air from the air nozzle and the wind pressure of the compressed air from one or more auxiliary air nozzles arranged on the rear side in the winding direction of the air nozzle. The method for manufacturing a pneumatic tire with a sealant according to any one of claims 4 to 6, wherein a string-shaped sealant is pressed against the inner peripheral surface of the tire.   The method for manufacturing a pneumatic tire with a sealant according to any one of claims 4 to 7, wherein an ejection port of the air nozzle has a circular shape and an inner diameter of 0.5 to 3.0 mm. The method for manufacturing a pneumatic tire with a sealant according to any one of claims 5 to 8, wherein the ejection port of the air nozzle is movable in the tire axial direction with respect to the nozzle.   The air nozzle according to any one of claims 5 to 9, wherein the air nozzle includes a plurality of ejection ports arranged in the tire axial direction, and compressed air is switched and ejected from one of the plurality of ejection ports. A method for manufacturing a pneumatic tire with a sealant.   The method for manufacturing a pneumatic tire with a sealant according to any one of claims 5 to 10, wherein a height in a tire radial direction from an outlet of the air nozzle to an inner peripheral surface of the tire is adjustable. An apparatus for manufacturing a pneumatic tire with a sealant having a sealant layer for preventing puncture on the tire inner peripheral surface,
A tire support that rotatably supports the tire in an upright state,
On the tire inner peripheral surface of the rotatably supported tire, an adhesive means to adhere while spirally winding a string-shaped sealant,
Pressing means for pressing the adhered string sealant against the inner peripheral surface of the tire before the next string sealant is adhered next to the adhered string sealant, manufacturing device.   The apparatus for manufacturing a pneumatic tire with a sealant according to claim 12, wherein the adhesive unit includes a nozzle that discharges the string-shaped sealant toward the inner peripheral surface of the tire.   14. The apparatus for manufacturing a pneumatic tire with a sealant according to claim 12, wherein the pressing means includes a roller for pressing the string-shaped sealant against the inner peripheral surface of the tire.   14. The apparatus for manufacturing a pneumatic tire with a sealant according to claim 12, wherein the pressing means includes an air nozzle for pressing the string-shaped sealant against the inner peripheral surface of the tire by jetting compressed air.   16. The apparatus for manufacturing a pneumatic tire with a sealant according to claim 15, wherein the pressing unit includes the air nozzle and one or more auxiliary air nozzles disposed rearward in the winding direction of the air nozzle.   The apparatus for manufacturing a pneumatic tire with a sealant according to claim 15 or 16, wherein the pressing means is capable of moving an ejection port of the air nozzle in a tire axial direction with respect to the nozzle.   18. The air nozzle according to claim 15, wherein the air nozzle includes a plurality of ejection ports arranged in a tire axial direction, and the pressing unit switches and ejects compressed air from one of the plurality of ejection ports. The manufacturing apparatus of a pneumatic tire with a sealant according to any one of the above.   The manufacturing apparatus for a pneumatic tire with a sealant according to any one of claims 15 to 17, wherein the pressing means is capable of adjusting a height in a tire radial direction from an ejection port of the air nozzle to an inner peripheral surface of the tire.

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