Rigid core

Abstract

A rigid core is efficiently, stably and very accurately assembled and disassembled without using a bolt. The rigid core is provided with: a core body (3) comprising a plurality of core segments (9) divided in the circumferential direction of the tire; a cylindrical core (5) for preventing the movement of each core segment (9) toward the inside in the radial direction, and inserted into the center hole of the core body (3); and a pair of side plates (6U, 6L) for preventing the movement of each core segment (9) in the axial direction thereof, by being positioned on both sides in the axial direction of the core body (3), and by sandwiching and holding the core body (3) between the inside surfaces thereof. A first dovetail part (16) is formed on the outer circumferential surface of the core (5), and a second dovetail part (17) for engaging with the first dovetail part (16) is formed on the inner circumferential surface of each core segment (9). The side plate (6U, 6L) on one side is fixed to the end of the core (5) on one side thereof, and the side plate (6U, 6L) on the other side is equipped with a boss part (22) that projects therefrom and can be threaded into an internal thread (13) provided in the central hole of the core (5).

Description

technical field [0001] The present invention relates to a rigid core which is detachable from a pneumatic tire and which can be reinstalled with high precision and high efficiency. Background technique [0002] Recently, such as Figure 10 As shown in (A), in order to improve the forming accuracy of a pneumatic tire, a vulcanization method for a pneumatic tire is proposed (for example, Patent Document 1) by using a rigid core having an outer shape corresponding to the inner surface shape of the tire ( a) to achieve. In this method, tire constituent members such as innerliner, carcass ply, belt, sidewall rubber, and tread rubber are sequentially adhered to a rigid core (a) to form an unvulcanized tire ( t). The unvulcanized tire (t) is put into a vulcanization mold (b) together with a rigid core (a), and is vulcanized between the rigid core (a) as an inner mold and the vulcanization mold (b) as an outer mold. [0003] Such as Figure 10 As shown in (B), the core body (a1) ...

AI Technical Summary

Problems solved by technology

[0009] However, in this structure, automatic removal of the bolt (e) is not easy to achieve; moreover, there must be many bolts to be tightened

Therefore, the disassembly and assembly operation of the rigid core (a) is a lot of work and thus not very operable

In addition, it is difficult to determine the positioning of each of the core segments (c), thus prone to inaccurate

Therefore, it is difficult to assemble a rigid core with high precision and stability (a)

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