JPH0475122B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a split-mold type tire molding die and a method for manufacturing the same, particularly a split-mold type tire molding die having at least a plurality of divided tread parts and a manufacturing method thereof. wherein each of the plurality of tread parts has an inner circumferential surface consisting of a curved surface corresponding to at least the tread of the tire to be molded, and a profile part divided corresponding to the equatorial plane, and a profile part of the profile part; Split mold type tire molding die having a joint surface that comes into contact with the inner circumferential surface and having a net portion having ribs and/or lugs for molding the recessed portion of the tire to be molded, and manufacturing thereof. It is about the method.

In general, tire molding molds are of the split mold type, as shown in FIG. 1 (side sectional view) and FIG. A so-called split-mold type tire molding tool is composed of a tread part 1 and shoulder parts 2, 2', which are formed by combining a plurality of arc-shaped sector molds 1', 1', . . . into an annular shape. It is often a mold (in the figure, the code 1 is the tread part, 1, 1', ... are the sector molds, 2
and 2' are shoulder parts, 3 and 3' are abutment surfaces, 4 is tread surfaces, CL is center line, SL
represents a sector line). The applicants of the present application have already developed a method for manufacturing a tire molding die using a split mold method in which a set of multiple tread parts is formed from one block of tread rings (Japanese Patent Application No. 54-62441). ) is proposed. This proposal (hereinafter referred to as proposal A) contributes to providing a high-precision, low-cost split mold type tire molding die by manufacturing one set of tread parts from one tread ring. are doing.
Furthermore, the applicants of the present application have proposed a tire molding mold in which the tread portion is composed of a profile ring and a net ring, and a method for manufacturing the same (Japanese Patent Application No. 58-95302). This proposal (hereinafter referred to as proposal B) greatly contributes to a significant reduction in manufacturing costs and manufacturing period. Therefore, it is considered that by applying Proposal B to Proposal A above, it will be possible to provide a split-mold type tire molding die with even lower cost and higher precision. When dividing the profile ring and net ring manufactured by the above proposal B, due to accuracy problems, it is necessary to divide the profile ring and net ring manufactured by the above proposal B into one piece. The above proposal A
It is desirable to cut based on the However, in split mold type tire molding molds, the outer diameter of the net ring is larger than the inner diameter at both end faces of the profile ring. There is a problem that it cannot be combined with a ring.

The present invention aims to solve the above problems and combines the profile ring and the net ring by dividing the profile ring into two parts corresponding to the equatorial plane. The purpose of the present invention is to provide a high-precision, low-cost split-mold type tire molding mold and its manufacturing method by manufacturing the mold in multiple parts under the combined state. It is said that This will be explained below with reference to the drawings.

FIG. 3 shows an embodiment of the tire molding mold of the present invention, in which FIG. 3A shows a sectional view and FIG. 3B shows a developed plan view of the tread portion. Fourth
5 and 5 are explanatory diagrams for explaining the method of manufacturing a tire molding die of the present invention, and FIG. 6 is a sectional view of another embodiment of the present invention. Reference numbers 2 and 2' in the figure correspond to those in Figure 1, 5 is the net ring, 5-1 is the joint surface, and 5' is the net ring.
Ring material, 6 is upper profile ring,
6' is the lower profile ring, 6-1 and 6'-1 are the inner peripheral surfaces of the profile rings, 6-2
and 6'-2 is the abutment surface, 7 is the holder, and 8
9 is a rib, 9 is a lug, 10 is a connecting member, 11 is a bold, 12 and 13 are fixing means, and 14 is a blade.

An embodiment of the split-mold type tire molding mold of the present invention illustrated in FIGS. 3A and 3B includes a net ring 5, an upper profile ring 6, and a lower profile ring 6'. The net ring 5 is fixed to the upper profile ring 6 and the lower profile ring 6' by a fixing means 12 such as a bolt or a tapered pin. Further, the upper profile ring 6 and the lower profile ring 6' are further fixed to the holder 7 by fixing means 13 such as a vault. Note that the upper profile ring 6 and the lower profile ring 6' are aligned with the center line as shown in FIG. 3A.
CL (in the present invention, the equatorial plane refers to the center
(which is a plane including line CL), but is fixed by a vault 11.
Then, the profile ring inner peripheral surfaces 6-1 and 6'-1 correspond to the tread surface of the tire to be formed,
The ribs 8, lugs 9, blades 14, etc. of the net ring 5 correspond to the recesses of the tire to be formed. The illustrated connecting member 10, when not connected to other ribs 8 or lugs 9, such as the central rib 8 in the illustrated embodiment of FIG.
This is made possible by the necessity of configuring the ring. The embodiment shown in FIG. 3 of the present invention has basically the same configuration as proposal B described at the beginning of this specification, except that the profile ring is divided into two parts. Please note that the profile
The reason why the ring is divided into two parts is to enable the profile ring and the net ring before being cut to be integrally combined.

Next, the manufacturing method of the present invention will be explained with reference to FIGS. 4 and 5. As shown in FIG. 4A, inner circumferential surfaces 6-1 and 6'-1 are curved surfaces corresponding to the treads of the tire to be molded, and surfaces 6-2 and 6'-1 abut against the shoulder portions 2 and 2'. 6'-2, an upper profile ring 6 and a lower profile ring 6' are manufactured. Figure 4A shows its cross-sectional shape,
In the illustrated case, it goes without saying that it is formed in a ring shape.

Next, the manufacturing process of the net ring 5 will be explained. The net ring 5 according to the invention is manufactured by applying proposal B described at the beginning of this specification. That is, first, a net ring material 5' shown in FIG. 4B is manufactured by machining. In manufacturing the net ring material 5', at least the joint surface 5 corresponding to the inner circumferential surfaces 6-1 and 6'-1 of the upper profile ring 6 and lower profile ring 6' is −
1 shall be finished with high precision using, for example, an NC lathe. Further, although FIG. 4B shows its cross-sectional shape, it goes without saying that it is formed in a ring shape. Then, as shown in FIG. 4C, ribs 8 and lugs 9 corresponding to the recesses of the tire to be formed are formed, for example, by electrical discharge machining.

The net ring 5, upper profile ring 6 and lower profile ring 6' manufactured as described above are assembled as shown in FIG. 3A. In the present invention,
Since the profile ring is divided into an upper profile ring 6 and a lower profile ring 6', the ring-shaped net ring 5, the upper profile ring 6 and the lower profile ring 6' are separated. This makes it possible to combine them. In this way, with the net ring 5, the upper profile ring 6 and the lower profile ring 6' combined together, the Cut into multiple blocks as shown in Figure 5. Note that the sector line SL shown in dotted lines in FIG. 5 indicates the cutting portion.

FIG. 6 shows another embodiment of the invention.
In the embodiment shown in FIG. 3 described above, the lugs 9 are also provided on the shoulder portions 2 and 2';
In the embodiment shown in FIG. 6, all of the ribs 8 and lugs 9 are formed by the net ring 5, and basically has the same structure as the embodiment shown in FIG. 3 described above. be. The manufacturing method thereof is also basically the same as that described with reference to FIGS. 4 and 5. Incidentally, as a means for fixing the net ring 5 to the profile rings 6 and 6', the vault 11 is used in the embodiment shown in FIG.
As indicated by the welded portion 15 shown in the figure, the profile ring 6 is attached by means of welding or the like.
The joint ends of and 6' may be welded.

Although the net ring 5 in the embodiments shown in FIGS. 3 and 6 described above is composed of a plurality of ribs 8 and lugs 9, the net ring 5 in the present invention is not limited to this. Instead, although not shown, it is also possible to configure the structure in such a way that only the ribs 8 or only the lugs 9 remain. In this case, the ribs 8, 8,...
The net ring 5 is constructed by connecting the lugs 9, 9, . . . with the aforementioned connecting member 10.

As explained above, according to the present invention, by dividing the profile ring into two parts, the upper profile ring and the lower profile ring, the profile ring and the net ring can be formed into a ring shape. It is now possible to combine the
Since the combined state is divided into a plurality of blocks, it is possible to provide a tire molding die of a split mold type with high accuracy and low cost.

[Brief explanation of drawings]

Figure 1 is a side cross-sectional view for explaining a general example of a split mold type tire molding die, and Figure 2 is a side sectional view of the
A plan view of the tread portion 1 taken along the arrow A-A' in the figure, FIGS. 3A and 3B show an embodiment of a split mold type tire molding mold according to the present invention, and FIGS. 4A and 4B,
C and FIG. 5 are explanatory diagrams for explaining the manufacturing method of the present invention, and FIG. 6 shows another embodiment of the present invention. In the figure, 2 and 2' are shoulder parts, 5 is a net ring, 5-1 is a joint surface, 5' is a net ring material, 6 is an upper profile ring, and 6'
are lower profile rings, 6-1 and 6'
-1 is the inner peripheral surface of the profile ring, 6-2 and 6'-2 are abutment surfaces, 7 is a holder, 8 is a rib, 9 is a lug, 10 is a connecting member, 11 is a vault, 12 and 13 are fixed 14 represents a blade, and 15 represents a welded portion.

[Claims]

1. In a split-mold type tire molding mold having at least a plurality of divided tread parts, the tread part is a single annular mold having an inner circumferential surface consisting of a curved surface corresponding to at least the tread surface of the tire to be molded. a profile portion, and a net portion having a joint surface that comes into contact with the inner circumferential surface of the profile portion and having ribs and/or lugs for forming a concave portion of the tire to be molded, the net portion and the single-structure annular profile portion are cut in the sector direction, and the net portion is placed on the profile portion, so that the net portion and the profile portion are each in the sector direction. For tire molding using a split mold method, the tire is divided in a direction to form a tread portion, and the divided tread portions are joined together.

Claims (1)

A split mold type tire molding die according to claim 1, characterized in that: 3. The split mold type tire molding die according to claim 1, wherein the net portion is placed on the profile portion with only the lugs remaining. 4. A method for manufacturing a split-mold type tire molding mold having at least a plurality of divided tread parts, the mold having an inner circumferential surface formed by processing a curved surface corresponding to at least the tread surface of the tire to be molded. and an annular profile portion divided corresponding to the equatorial plane, and a rib for forming a concave portion of the tire to be formed, and having a joint surface that comes into contact with the inner circumferential surface of each of the profile portions; /Or after manufacturing an annular net portion having lugs, joining the divided profile portions at the divided portions, and then assembling the net portion annularly and integrally to the joined profile portions. , A plurality of the tread parts are manufactured by cutting the profile part and the net part in the sector direction, and the plurality of tread parts are assembled in an annular shape so that the corresponding cut surfaces of each of the tread parts are joined. A method for manufacturing a tire molding die using a split mold method, characterized by manufacturing a molding die. 5. The method of manufacturing a split mold type tire molding die according to claim 4, wherein the net portion is manufactured with only the ribs remaining. 6. The method of manufacturing a split mold type tire molding die according to claim 4, wherein the net portion is manufactured with only the lugs remaining. 7. Claim 4, characterized in that the net portion is manufactured by forming at least a portion of the net portion other than the joint surface by electrical discharge machining.
A method for manufacturing a tire molding die using a split mold method according to any one of Items 1 to 6.