JP4375890B2 - Tire molding method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a tire molding method, and more specifically, in a shaping bladderless second-stage molding drum, when stitching an unvulcanized tire, the deformation of the carcass cord is greatly reduced without impairing productivity, The present invention relates to a tire molding method with improved product accuracy.
[0002]
[Prior art]
Conventionally, in the shaping bladderless second-stage molding apparatus, as shown in FIG. 3, a carcass green Wa (unvulcanized state) in which a belt-tread member laminate 11 and a bead lock drum are fixed in advance via beads. the carcass material) and the carcass Green W a method to combine with stitching by stitching wheel 12 the member stack body 11 toward the spindle center by inflated is being performed.
[0003]
[Problems to be solved by the invention]
However, when the carcass green Wa and the member laminated body 11 are combined, the circumferential inertia force between the carcass bead portion 13 and the member laminated body 11 located at the outer diameter portion, and the circumferential shear during stitching. Due to the force, there is a problem that the deformation of the carcass cord is generated, the product is defective, and the productivity is impaired.
[0004]
An object of the present invention is to provide a tire molding method that can reduce the deformation distortion of a carcass cord and increase the product accuracy without impairing the productivity of the tire when stitching a member laminate.
[0005]
[Means for Solving the Problems]
In order to achieve the above-mentioned object, the present invention brings a belt with a rotational drive and a stitching wheel into contact with a belt and a tread laminated body so that a relative speed between the tire surface rotational speed and the surface movement speed of the rotational drive roller is obtained. The gist is that stitching is performed with a stitching wheel with a difference.
[0006]
The present invention is configured as described above, and a belt with a rotational drive and a stitching wheel are brought into contact with the belt and tread laminate, and a relative speed between the tire surface rotational speed and the surface movement speed of the rotational drive roller. By making the difference in the stitching by the stitching wheel, the deformation accuracy of the carcass cord can be reduced and the product accuracy can be improved without deteriorating the productivity of the tire.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
[0008]
Note that the same components as those in the conventional example are denoted by the same reference numerals and description thereof is omitted.
[0009]
FIG. 1 is a schematic front view of a shaping bladderless second-stage forming apparatus for carrying out the tire forming method of the present invention. The main spindles 1a and 1b are rotatable and relatively movable in the axial direction. The pair of bead lock drums 2a and 2b is detachably attached at a predetermined interval.
[0010]
The bead lock drums 2a and 2b are fixed with bead portions 3 attached to both ends of a carcass member W in which a steel cord is embedded. The carcass member W is shaped like a toroid, and the outer peripheral surface position of the carcass member W is fixed. In addition, the member laminate 4 of the belt member 4a and the tread member 4b molded in another molding stage is transported by a transfer device (not shown), and the outer peripheral surface of the carcass member W and the member laminate 4 are connected to each other. Hold Fret pressure bonding.
[0011]
In such a state, the belt / tread member laminated body 4 joined to the outer peripheral surface of the carcass member W shaped in a toroidal shape while rotating the carcass material W is stitched wheel 6 (in this embodiment). Although only one side is shown, it is actually arranged on the left and right sides), and is stitched and crimped along the outer peripheral surface of the carcass member W toward the main axis O.
[0012]
At this time, in the first embodiment of the present invention, a belt, a member laminate 4 of the tread, and a rotary drive with roller 7 and stitching wheel 6 is abutting, the tire surface rotational speed and the rotational drive with roller 7 The stitching wheel is used to make a difference in relative speed with respect to the surface moving speed , thereby reducing the deformation distortion of the carcass cord and improving the product accuracy.
[0013]
In addition, the relative speed difference between the tire surface rotation speed and the surface movement speed of the roller 7 with rotation drive is optimally 5 to 10%, and preferably 5 to 10% at maximum than the tire surface rotation speed. Is good.
[0014]
Further, it is preferable that the roller with a rotational drive and the stitching wheel are stitched close to each other within a range of 45 ° on the outer periphery of the tire, and in this embodiment, the arrangement is 22.5 degrees. From 0 degrees to a maximum of 45 degrees in the counter-rotating direction is effective.
[0015]
The rotation drive source of the roller 7 with rotation drive is preferably a motor capable of speed control. It is also effective in an air motor that makes use of the contact surface slip characteristics, and the pressing portion of the roller 7 with rotational drive is not limited to the outer diameter center but can be extended to the belt region of the tire outer diameter portion.
[0016]
【The invention's effect】
In the present invention, as described above, the rotational drive roller and the stitching wheel are brought into contact with the belt / tread laminated body, and the difference in relative speed between the tire surface rotational speed and the surface movement speed of the rotational drive roller is determined. Since the stitching wheel is used for stitching, the existing equipment can be used effectively, and the product accuracy can be improved by reducing the deformation distortion of the carcass cord without impairing the productivity of the tire.
[Brief description of the drawings]
FIG. 1 is a schematic front view of a shaping bladderless second-stage tire forming apparatus embodying the present invention.
FIG. 2 is an explanatory diagram of a method of stitching with a stitching wheel with a difference in relative speed between a tire surface rotation speed and a roller with rotation drive according to the present invention.
FIG. 3 is an explanatory view of a conventional method of stitching a member laminate.
[Explanation of symbols]
1a, 1b Main shaft 2a, 2b Bead lock drum 3 Bead part 4a Belt member 4b Tread member 4 Member laminate 6 Stitching wheel 7 Roller W carcass member with rotational drive

Claims (3)

Tire molding in which a belt and tread laminate are fitted on the outer circumferential surface of a carcass member shaped in a toroidal shape, and the belt and tread laminate are stitched toward the main axis by a stitching wheel while rotating the carcass member In the method, the belt and the tread laminated body are brought into contact with a roller with a rotational drive and a stitching wheel, and stitching is performed with a difference in relative speed between the tire surface rotational speed and the surface movement speed of the rotationally driven roller. A tire molding method that stitches with a wheel. The tire molding method according to claim 1, wherein a relative speed difference between the tire surface rotation speed and the surface movement speed of the roller with rotation drive is set to 5 to 10%.   The tire molding method according to claim 1 or 2, wherein the roller with rotation drive and the stitching wheel are stitched close to each other within a range of 45 ° on the outer periphery of the tire.

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