JPH0243027A - Manufacture of reinforcing layer of tire - Google Patents

Abstract

PURPOSE:To prevent end-open from developing in tire vulcanizing process by a method wherein a tire reinforcing layer is produced by winding a reinforcing cord at the apex of a carcass so as to make the winding pitch of the reinforcing cord denser at the portion beneath the peripheral groove of a tread pattern. CONSTITUTION:The speed ratio of the revolving speed of a tire forming drum and traversing speed is controlled so as to be arbitrary value in corresponding to a tread pattern Tr at the winding of a reinforcing cord W at the apex K of a carcass by setting the tread pattern Tr of a tire T after vulcanizing forming in advance at the control unit of both the rotary driving device 4 of the tire forming drum 1 and the driving device 11 of a traverser 6. As a result, the winding pitch Pw of the reinforcing cord W at the portion beneath the peripheral groove Q of the tread pattern Tr becomes denser than other winding pitch Pw at the winding of the reinforcing cord W at the apex K of the carcass. Thus, the end-open of the reinforcing cord W at vulcanizing forming is effectively prevented from developing and consequently the performance of a tire can be improved.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a method for manufacturing a tire reinforcing layer, and more specifically, in the tire reinforcing layer manufacturing process, the winding of the reinforcing cord is performed by changing the pitch around the tread pattern. The present invention relates to a method for producing a tire reinforcing layer in which the lower portion of the directional groove is tightly wrapped to prevent end-opening during the tire vulcanization process.

[Prior Art] Conventionally, in the process of forming a radial tire, a reinforcing cord is sequentially wound between the top of the carcass and the tread with an even pinch while driving a forming drum and a traverse device at a constant speed. 2. Description of the Related Art There are known methods for manufacturing a tire reinforcing layer and methods for manufacturing a tire reinforcing layer by wrapping a rubber coated strip consisting of a plurality of cords.

[Problem that the invention seeks to solve]

By the way, even if the reinforcing layer of the tire is formed by sequentially winding reinforcing cords at equal pitches between the top of the carcass and the tread during the molding process as described above, the reinforcing cords will not be formed by the mold during the tire vulcanization process. When pressure is applied, the pitch of the reinforcing cord, which had been wrapped in an even pinch, becomes disordered, and the ends become open (the pitch of the reinforcing cord is wider than other pitches), especially in the lower part of the circumferential groove of the tread pattern. There is a problem in that the tire performance such as high-speed durability and ride comfort is deteriorated.

[Purpose of the invention]

This invention was devised by focusing on such conventional problems, and assuming in advance that the reinforcing cord would be pinched irregularly during the tire vulcanization process, the winding of the reinforcing cord is adjusted to the pitch of the tread pattern. A method for manufacturing a tire reinforcing layer that tightly wraps the lower part of the circumferential groove to effectively prevent end-opening during the tire vulcanization process and significantly improve tire performance such as high-speed durability and ride comfort. The purpose is to provide the following.

[Means to solve the problem]

In order to achieve the above object, the present invention sets the tire tread pattern after vulcanization molding in advance in the control unit of the rotation drive device of the forming drum and the drive device of the traverse device, and when wrapping the reinforcing cord around the top of the carcass. By controlling the speed ratio between the drum rotation speed and the traverse feed speed to a predetermined value in accordance with the tread pattern, when the reinforcing cord is wound around the top of the carcass, the lower part of the circumferential groove of the tread pattern is controlled. The gist of winding the reinforcing cord is to wrap the reinforcing cord at a dense pitch to form a tire reinforcing layer.

[Action of the invention]

This invention is constructed as described above, and the reinforcing cord is wound at a tight pitch under the circumferential groove of the tread pattern to form a tire reinforcing layer. It is characterized by effectively preventing tire opening and improving tire performance.

[Embodiments of the invention]

The present invention will be described in detail below based on the accompanying drawings.

FIG. 1 shows a schematic configuration diagram of a tire reinforcing layer manufacturing apparatus according to the present invention, in which 1 is a tire forming drum, 2 is a drum shaft, and 3 is a bearing that rotatably supports the drum shaft. The tire forming drum 1 is rotatably driven by a rotational drive device 4 (drive motor).

A traverse device 6 equipped with a reinforcing cord W supply device 5 is installed on the side of the tire building drum 1.

As shown in FIGS. 1 and 3, the traverse device 6 includes two linear guide rods 10a sandwiching a ball screw 9 rotatably supported at the center between opposing side walls 8 of a support frame 7.

10b is arranged in parallel, Bono? The screw 9 connects to a drive device 11 (traverse motor) installed on the outside of the side wall 8.
It is designed to be rotationally driven.

The ball screw 9 and the two linear guide rods 10
At the top of a and 10b, there is a support plate 12 on which a reinforcing cord W supply device 5 is installed! The support plate 12 is screwed into the ball screw 9 through a nut 13, and is slidably fitted into the two linear guide lofts IOA and 10B through bearings 14a and 14b. There is.

The reinforcement cord W supply device 5 includes a support plate 12.
A reel-shaped supply member 16 on which a reinforcing cord W is wound is installed via a bracket 15, and from this supply member 16 a top part K of the carcass wound on the tire forming drum 1 is supplied.
One reinforcing cord W is continuously wound around the reinforcing cord W at predetermined pitch intervals.

Therefore, the traverse device 6 configured as described above,
When the ball screw 9 rotates due to the forward and reverse rotational drive of the drive device 11, the support plate 12 connects to the two linear guide rods 10a and 10f via a nut 13 that is screwed into the ball screw 9.
ob, and at the same time, the supply member 16 also moves horizontally along the surface of the tire building drum 10 to wrap the reinforcing cord W around the top K of the carcass.

Next, a method for manufacturing a tire reinforcing layer will be described.

First, in a control section (not shown) of the rotational drive device 4 of the tire forming drum 1 and the drive device 11 of the traverse device 6,
The tire tread pattern after vulcanization molding is set in advance.

That is, as shown in FIG. 2, when setting the tread pattern Tr of the tire T after vulcanization molding and wrapping the reinforcing cord W around the top K of the carcass, the drum rotation speed is adjusted in accordance with the tread pattern Tr. Control the speed ratio to the traverse feed speed to an arbitrary value. As a result, when wrapping the reinforcing cord W around the carcass top K, the tread pattern T
The winding of the reinforcing cord in the lower part of the circumferential groove Q of r is at a pitch of p.
As shown in FIG. 2, w is denser than pitch Pw in other windings.

By configuring the tire reinforcing layer in this way, it is possible to effectively prevent the reinforcing cord W from opening at the end during vulcanization molding, and improve tire performance.

〔Effect of the invention〕

This invention provides the following advantages: - As described above, the tire tread pattern after vulcanization is set in advance in the control unit of the rotation drive device of the forming drum and the drive device of the traverse device, and when the reinforcing cord is wrapped around the top of the carcass. By controlling the speed ratio between the drum rotation speed and the traverse feed speed to a predetermined value in accordance with the tread pattern, when the reinforcing cord is wound around the top of the carcass, the lower part of the circumferential groove of the tread pattern is controlled. Since the reinforcing cord is wrapped in a tight pinch manner to form the tire reinforcing layer, the following excellent effects can be achieved.

(a) Assuming in advance that the reinforcing cord may be pinched irregularly during the tire vulcanization process, the reinforcing cord is wrapped at a pitch that is tightly wrapped under the circumferential groove of the tread pattern. End-opening during the vulcanization process can be effectively prevented.

(b) Tire performance such as high-speed durability and ride comfort can be significantly improved.

(C) Also, since it is performed automatically, work efficiency can be improved, and the operating rate can be improved.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram of a tire reinforcing layer manufacturing apparatus according to the present invention, FIG. 2 is a partial sectional view of a tire having a tire reinforcing layer, and FIG. 3 is a plan view of a traverse device. 1... Tire forming drum, 2... Drum shaft, 4...
・Rotary drive device (drive motor), 5... Reinforcement cord W
6... Traverse device, 11... Drive device (traverse motor), W... Reinforcement cord, Tr
...Tire tread pattern. Figure 3

Claims (1)

[Claims] 1. While rotating the forming drum at a predetermined number of rotations, a traverse device equipped with a reinforcing cord feeding device is placed on the top of the carcass wrapped around the forming drum while reciprocating horizontally. In a method of manufacturing a reinforcing layer of a tire by sequentially winding reinforcing cords, a tire tread pattern after vulcanization molding is set in advance in the control section of the rotation drive device of the forming drum and the drive device of the traverse device. , when wrapping the reinforcing cord around the top of the carcass, the speed ratio between the drum rotation speed and the traverse feed speed is controlled to a predetermined value in accordance with the tread pattern; A method for manufacturing a tire reinforcing layer, comprising winding reinforcing cords at a dense winding pitch under a circumferential groove of the tread pattern to constitute a tire reinforcing layer. 2. The method for manufacturing a tire reinforcing layer according to claim 1, wherein a plurality of traverse devices each having a reinforcing cord supply device are installed to simultaneously wrap a plurality of reinforcing cords around the top of the carcass.