Method for producing webs for reinforcement ply of a tyre by butt-joining of straight-wire strips

Abstract

The present invention concerns a method for producing webs (1) intended to be included in the makeup of a reinforcement ply (2) for a tyre (20), said method comprising a preparation step (a) during which a plurality of straight-wire strips (7, 107, 207) are prepared, each formed from a plurality of continuous reinforcement wires (4) immersed in a layer of rubber (5), a butt-joining step (b), during which said straight-wire strips (7, 107, 207) are butt-joined, two-by-two, in order to form a straight-wire ply (3), than a cutting step (c), during which the straight-wire ply engages (3) in a cutter (8) and the straight-wire ply (3) is cut transversely so as to form the webs. In said method, the front width (W3) of the straight-wire ply (3) which is produced during the butt-joining step (b) then engaged in the cutter (8) is greater than or equal to 50%, 75%, 80%, or even 90% of the inlet width of the cutter (W8), while the front width (W7, W107, W207) of the widest of the straight-wire strips is less than or equal to 50%, 40%, 25%, 10% or even 5% of said cutter inlet width (W8).

Description

technical field [0001] The present invention relates to the field of tire manufacturing, in particular to a pneumatic tire for mounting to a moving vehicle. [0002] More specifically, the invention relates to the manufacture of reinforcing plies used in the construction of such tires. Background technique [0003] Known practice is to manufacture reinforcing plies by first producing by calendering a ply called a straight cord ply comprising a plurality of rubber oriented parallel to the longitudinal direction of said ply and embedded with rubber. A reinforcing ply in the middle; then a portion of the straight cord ply (called a “web”) is cut from this straight cord ply by using a cutter at a predetermined cutting angle; then by using them parallel to the reinforcing cords The edges of the web are joined at both ends to form a reinforcing ply in which the reinforcing cords form an angle with respect to the longitudinal direction of the ply called a "ply angle" defined by T...

AI Technical Summary

Problems solved by technology

[0023] However, such a device presents a high degree of complexity and requires in particular numerous adjustments to position the tool in length and offset relative to the axis of the cylinder in order to specifically define the width of the removed reinforcing ply, or to adjust the cylinder The center-to-center distance of , for a given reinforcement ply width, which adjusts the length of each portion of the strip in the reinforcement ply, and thus the ply angle

[0024] Therefore, such a device can prove to be relatively expensive to implement and has certain disadvantages in terms of reliability

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