JP4925521B2 - Manufacturing method of tire component and tire - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a method for manufacturing a tire component such as an inner liner.
[0002]
[Prior art]
In the conventional general method, a tire constituent member such as an inner liner is manufactured in advance as a continuous belt-like member having a predetermined width, and this is wound around a carriage.
In use, this is unrolled and cut into fixed lengths, and the cut tire constituent member is supplied to a molding drum and attached to the drum.
[0003]
[Problems to be solved by the invention]
Thus, the preparatory process before using a tire structural member enlarges, and equipment space is also required widely.
It is also necessary to prepare a cart for each size.
Furthermore, the thickness of the coating rubber is single and cannot be adjusted.
[0004]
The present invention has been made in view of such a point, and the object of the present invention is to provide a simple method for manufacturing a tire constituent member in which the thickness of the covering rubber can be freely adjusted with a compact facility.
[0018]
[Means for solving the problems and effects]
According to the first aspect of the present invention, an inner liner is formed by spirally winding a ribbon-shaped rubber of a normal rubber type (a) on a polymer film provided around a drum so as to partially partially overlap. Part (L1) is formed in the center in the width direction, and then a particularly hard rubber type (b) ribbon-like rubber is partially wound on the left and right in the width direction of the inner liner part (L1) and wound in a spiral shape toe rubber part ( L2, L2) is formed, and then a ribbon rubber of a hard rubber type (c) is partially overlapped on the left and right outer sides in the width direction of the left and right toe rubber parts (L2, L2), respectively, and spirally wound to form a rubber chafer part (L3 , L3), and an inner liner in which a plurality of types of rubber layers are formed in the same layer.
[0019]
Different types of rubber can be formed in the same layer, and the most suitable rubber can be easily applied to each part of the tire.
[0021]
The inner liner that forms the inner layer of the pneumatic tire is efficiently manufactured with small equipment.
A tire excellent in airtightness can be easily produced by the inner liner.
[0022]
A second aspect of the present invention is a tire manufactured using the inner liner manufactured by the manufacturing method of the first aspect .
[0023]
An inner liner is efficiently manufactured with a small equipment, and a tire is manufactured using the inner liner , so that productivity is good.
[0024]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment according to the present invention will be described with reference to FIGS.
The present embodiment relates to a method for manufacturing an inner liner which is a tire constituent member provided in an inner layer of a tire. FIG. 1 shows a schematic perspective view of the inner liner manufacturing apparatus 10.
[0025]
A drum 13 is rotatably supported on a base 12 that is movable on a rail 11.
Accordingly, the drum 13 can be rotated by the motor provided on the base 12 and can be moved together with the base 12 in the rotation axis direction.
[0026]
An extruder 15 is disposed with the die facing the drum 13.
The extruder 15 forms the extruded rubber material into a ribbon shape from the die by the rotation of the screw and extrudes it, and supplies the ribbon rubber 1 to the drum 13 from the side.
[0027]
On the other hand, the cylindrical polymer film 2 is flattened and wound around the winding roll 16, and the cylindrical polymer film 2 unwound from the winding roll 16 is cut by the cutter 17 for the length of one tire. Then, it is cut into a substantially cylindrical shape and is provided around the outer peripheral surface of the drum 13.
[0028]
In this way, the ribbon-like rubber 1 is supplied from the extruder 15 onto the cylindrical polymer film 2 provided around the drum 13.
Since the drum 13 moves in the axial direction while rotating, the ribbon-like rubber 1 supplied from the extruder 15 is spirally wound on the cylindrical polymer film 2.
[0029]
A cylindrical inner liner 3 is formed on the tubular polymer film 2 by adjusting the moving speed in the axial direction with respect to the rotational speed of the drum 13 so that the ribbon-like rubber is partially overlapped and spirally wound.
[0030]
In this way, when the cylindrical inner liner 3 having the cylindrical polymer film 2 attached to the inner layer is manufactured, the cylindrical inner liner 3 is supplied to the molding drum as it is in a cylindrical shape, and is provided around the belt. Tread rubber is wound and vulcanized.
[0031]
At the time of vulcanization, since the cylindrical polymer film 2 is stuck inside the inner liner 3, the polymer film 2, which is a thermoplastic resin, can replace the bladder and perform bladderless vulcanization. .
[0032]
Since the ribbon-like rubber 1 is a narrow band-like rubber member, the supply and winding device to the cylindrical polymer film 2 provided around the extruder 15 and the drum 13 is compact, and the equipment can be downsized.
[0033]
Since the ribbon-like rubber 1 molded and extruded by the extruder 15 is directly supplied to the drum 13 without being wound and stored, no storage facility is required, which contributes to downsizing of the facility.
[0034]
Further, since the ribbon-like rubber 1 is wound around the drum 13, the size can be easily changed simply by changing the diameter of the drum, and inner liners of various sizes can be easily manufactured.
[0035]
When the ribbon-shaped rubber 1 has a width W and a thickness t, and the winding pitch P of the ribbon-shaped rubber 1 is set to 0.8 W by the rotational speed of the drum 13 and the moving speed in the axial direction, the ribbon-shaped rubber 1 was wound spirally. As shown in FIG. 2, the ribbon-shaped rubber 1 has a thin inner liner 3 as shown in FIG.
When the winding pitch P of the ribbon-like rubber 1 is set to 0.2 W, a thick inner liner 3 is manufactured as shown in FIG.
[0036]
Thus, the thickness of the inner liner 3 is determined by adjusting the moving speed in the axial direction with respect to the rotational speed of the drum 13 by adjusting the winding pitch P of the ribbon rubber 1 to what percentage of the width W of the ribbon rubber 1. It can be freely formed.
[0037]
In addition, by adjusting only the moving speed in the axial direction while keeping the rotation speed of the drum 13 constant, the winding pitch can be changed and the thickness of the inner liner can be freely formed.
Conversely, the winding pitch can be changed by adjusting the rotational speed while keeping the axial movement of the drum 13 constant.
Incidentally, in the present embodiment, the drum 13 is moved in the axial direction, but the extruder 15 may be moved in the axial direction.
[0038]
The cylindrical inner liner 3 has a tread portion at the center and a shoulder portion at the left and right, and a left and right portion from the side portion to the bead portion. The high part.
[0039]
Therefore, in order to spirally wrap the ribbon-like rubber 1 on the cylindrical polymer film 2 provided around the drum 13, as shown in FIG. 4, first, a large pitch P (from the end portion (left end portion in FIG. 4)) For example, 0.6 to 0.8 W) is wound, and the winding is changed to a small pitch P ′ (for example, 0.2 to 0.4 W) from the middle. In the range C, the inner liner 3 is formed thick, and the lateral ranges S and S on both the left and right sides thereof are formed thin.
[0040]
That is, it is formed thick from the tread part to the shoulder part with the highest elongation rate, so when the same part swells and expands at the time of molding, the entire inner liner can be configured with a substantially uniform and necessary thinness, A tire excellent in airtightness can be manufactured while achieving weight reduction.
[0041]
Since the inner liner 3 is configured by overlapping ribbon-like rubber, there is a possibility that the inner liner 3 will break at the seam when it expands during molding. However, the polymer film 2 provided inside the inner liner 3 works as a core material. The inner liner 3 can be prevented from cracking.
[0042]
Especially for tires with a flatness ratio of 80% or more, the above effect is remarkable by using a polymer film. However, for tires with a flatness ratio of 50% or less, a polymer film is not so necessary and a polymer film is not used. Also good.
[0043]
In the case of a tire with a small flatness ratio, the shoulder portion bulges particularly greatly during molding, so that the ribbon-like rubber 1 is spirally wound around the cylindrical polymer film 2 as shown in FIG. The inner liner 20 is formed by winding the portions that become the shoulder portions 20a, 20a that are somewhat separated from each other with a smaller pitch than the other portions.
The portion to be the shoulder portion is formed to be 2 to 10% thicker than the other portions.
[0044]
When the carcass 21 is wound on the inner liner 20 and internal pressure is applied by a molding machine to form a toroidal shape as shown in FIG. 6, the shoulder portion 20a is particularly elongated so that the entire inner liner is substantially uniform and Constructed with the required thinness.
[0045]
At the time of vulcanization molding, the inner liner 20 is wrapped with the bead core 22 at both ends together with the carcass 21, and the tread member 24 is wound around the carcass 21 with the belt member 23 sandwiched between the center and the side. Wall 25 is attached.
[0046]
Next, a plurality of extruders may be prepared so that ribbon-shaped rubbers made of different types of rubber can be supplied to the drum, and the plurality of types of ribbon-shaped rubbers may be partially wound respectively.
FIG. 7 is an example of such a configuration, and three types of rubbers a, b, and c are used.
[0047]
The inner liner part L1 which is wide from the tread part inside the left and right side parts uses a rubber type a having a normal hardness as an inner liner, and uses a particularly hard rubber type b as a toe rubber part L2 of the part which hits the toe of the bead part. Further, a hard rubber type c is used as the rubber chafer portion L3 outside the bead portion.
Rubber type a is normal hardness, rubber type c is harder than rubber type a, and rubber type b is the hardest.
[0048]
As a procedure for winding the ribbon-shaped rubber, first, a ribbon-shaped rubber of a rubber type a having a normal hardness is wound around the polymer film 2 provided around the drum to form the inner liner portion L1 at the center, and then particularly hard. A ribbon-type rubber of rubber type b is partially overlapped and wound on the inner liner part L1 to form a toe rubber part L2 on the left and right, and finally a ribbon-like rubber of a hard rubber type c is partially overlapped on the toe rubber part L2. The rubber chafer L3 is formed on the left and right.
[0049]
When the inner liner 30 formed in this way is integrated with the carcass 32 and the side wall 33 is overlapped and vulcanized and molded, the bead core 31 is wound around as shown in FIG. The toe rubber part L2 forms an edge.
Therefore, the toe rubber part L2 constituting the bead part of the tire is formed of the hard rubber type b, and the rigidity can be increased.
[0050]
Thus, different types of rubber can be partially coated, and the most suitable rubber can be easily applied to each part of the tire.
By wrapping ribbon-shaped rubbers of different rubber types in a spiral shape at appropriate pitches, tire components having appropriate shapes and properties for each part can be easily manufactured by a small manufacturing apparatus. It also contributes to the improvement of productivity.
[0051]
In the above embodiment, the ribbon-like rubber 1 is spirally wound on the cylindrical polymer film provided around the drum. However, in the case where the cylindrical polymer film is not used, a toroidal core is used. In some cases, a tire-like member such as an inner liner is formed by winding a ribbon-like rubber thereon as a support.
[0052]
In the above-described embodiment, the inner liner is formed on the cylindrical polymer film. However, not only the inner liner but also a ribbon-like rubber is spirally wound on the cylindrical polymer film and the price Kim is used. A rubber or the like may be formed.
[0053]
Further, in the case of a tire in which skim rubber is formed of ribbon-like rubber and the carcass are stacked two times, the first carcass is used as a support, and ribbon-like rubber is spirally wound thereon to form skim rubber. The second carcass wound on the top is adhered to the first carcass through the skim rubber.
[0054]
Further, a complicated shape such as a side wall can be obtained by winding a ribbon-like rubber on a drum or toroidal core as a support and winding it in a spiral while changing the winding pitch.
9, FIG. 10 and FIG. 11 are examples showing different sidewall shapes.
[0055]
The side wall 41 shown in FIG. 9 has a shape in which one low mountain 41a is formed with the thickness gradually increasing from both sides to the central portion. The side wall 42 shown in FIG. The side wall 43 shown in FIG. 11 has the same shape as that of the side wall 41 as a basic shape, and has an outer surface such as a curbstone or the like. The protrusion 43a for buffering is formed.
[0056]
Thus, by winding the ribbon-like rubber spirally while changing the winding pitch, it is possible to easily form tire constituent members having various shapes, fine ridge shapes, and the like.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view of an inner liner manufacturing apparatus according to an embodiment of the present invention.
FIG. 2 is a partial cross-sectional view of an inner liner having a large winding pitch of ribbon-like rubber.
FIG. 3 is a partial cross-sectional view of an inner liner with a small winding pitch of ribbon-like rubber.
FIG. 4 is a cross-sectional view of an inner liner formed by changing the winding pitch of ribbon-like rubber.
FIG. 5 is a cross-sectional view of another inner liner formed by changing the winding pitch of ribbon-like rubber.
FIG. 6 is a cross-sectional view showing a shape when molded using the inner liner.
FIG. 7 is a cross-sectional view of an inner liner formed by changing the rubber type of ribbon-like rubber.
FIG. 8 is a cross-sectional view of a bead portion of a tire molded using the inner liner.
FIG. 9 is a cross-sectional view of a side wall formed by winding a ribbon-like rubber in a spiral shape.
FIG. 10 is a cross-sectional view of another side wall formed by forming a ribbon-like rubber by spirally winding it.
FIG. 11 is a cross-sectional view of still another side wall formed by winding and molding a ribbon-like rubber.
[Explanation of symbols]
1 ... Ribbon rubber, 2 ... Cylindrical polymer film,
10 ... Inner liner manufacturing equipment, 11 ... Rail, 12 ... Base, 13 ... Drum, 15 ... Extruder, 16 ... Winding roll, 17 ... Cutter,
20 ... Inner liner, 21 ... Carcass, 22 ... Bead core 22, 23 ... Belt member, 24 ... Tread member, 25 ... Side wall,
30 ... Inner liner, 31 ... Bead core, 32 ... Carcass, 33 ... Side wall,
41, 42, 43 ... side wall.

Claims (2)

Wrap the inner liner part (L1) in the center in the width direction on a polymer film around the drum. Formed into
Next, a ribbon-shaped rubber of a particularly hard rubber type (b) is partially overlapped on the left and right in the width direction of the inner liner part (L1) and wound spirally to form a toe rubber part (L2, L2),
Next, a rubber chafer part (L3, L3) is formed by overlapping a hard rubber type (c) ribbon-like rubber partly on the left and right outer sides of the left and right toe rubber parts (L2, L2) in a spiral manner,
An inner liner in which a plurality of types of rubber layers are formed in the same layer is manufactured. A tire manufactured using the inner liner manufactured by the manufacturing method according to claim 1.

Images