JPH0635160B2 - Large tire molding method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for forming a large tire by sticking a tread wider than the maximum width of a rubber sheet supplied from a calender roll on a green case.

Conventional technology Generally, a tire is formed by attaching a tread onto a cylindrical green case and then deforming it into a toroidal shape, and then vulcanizing it to form it, or by attaching the tread onto the toroidal green case. After being attached, it is vulcanized and molded. Here, the above-mentioned tread may be formed by sticking a rubber sheet supplied from a calender roll a plurality of times, and the maximum width of such a rubber sheet is determined by the axial length of the calender roll. Therefore, when molding a large tire, the axial length of the calender roll may be lengthened to correspond to the width of the tread. There is a problem that the supply becomes difficult, the calender roll becomes large, and the equipment cost becomes expensive.

Problems to be Solved by the Invention The present invention solves the conventional problems that it is difficult to supply a rubber sheet having a uniform gauge, the calender roll becomes large, and the equipment cost becomes high.

Means for Solving Problems The problem is that the space occupied by the tread is divided into a plurality of block areas whose width is narrower than the maximum width of the rubber sheet, and then these block areas are adjusted in width. It is possible to solve it by filling it up sequentially.

Operation First, the space occupied by the tread, which is wider than the maximum width of the rubber sheet, is divided at least in the axial direction and, if necessary, further in the radial direction to form a plurality of block regions. Here, the width of each block area is set smaller than the maximum width of the rubber sheet. Next, a rubber sheet whose width is adjusted according to the width of the region is supplied to each block region and sequentially attached, and each region is successively filled with the rubber sheet to form a tread. In this way, the existing small calender roll can be used as it is, so that a rubber sheet having a uniform gauge can be supplied and the calender roll can be inexpensive.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, reference numeral 1 is a calender roll, and a rubber sheet 2 having a maximum width W is formed by passing rubber between the calender rolls 1. 3 and 4 are rubber sheets 2
Is a cutter that trims both ends in the width direction of the rubber sheet 2. When the cutters 3 and 4 approach and separate from each other by an equal distance in the axial direction of the calendar roll 1,
Adjust the width X of X to the desired value. Turn rolls 5 and 6 are parallel to the calender roll 1, and these turn rolls 5 and 6 turn the rubber sheet 2 fed from the calender roll 1 and supply it to the winder 7 for large tires. This winder 7 is rotatable and can be expanded and reduced in diameter.
Further, it can be moved in the axial direction by a moving mechanism (not shown). A cylindrical green case 8 is formed on the winder 7. Further, the rubber sheet 2 is attached on the green case 8 to form the tread 9, and the width Y of the tread 9 is the rubber sheet 2 described above.
Wider than the maximum width W of. Next, the operation of the embodiment of the present invention will be described.

First, after winding the cylindrical green case 8 on the winder 7, the tread 9 is formed on the green case 8. At this time, the space 10 occupied by the tread 9 is, for example, as shown in FIGS. Is divided into two in the radial direction and the inner space in the radial direction is divided into two in the axial direction to form three block regions a, b, c. Here, each block area a,
The widths Za, Zb and Zc of b and c are narrower than the maximum width W of the rubber sheet 2. Next, the rubber sheet 2 formed by the calendar roll 1 is supplied to the winder 7 and attached onto the green case 8. At this time, as shown in FIG. 2 (a), the attachment is started from the substantially trapezoidal block area a on the inner side in the radial direction, and the rubber sheets 2 are laminated one after another to fill the block area a with the rubber sheet 2. At this time, the width X of the rubber sheet 2 to be attached needs to be gradually narrowed, but the width X of the rubber sheet 2 is adjusted by moving the cutters 3 and 4 in the axial direction. In this way, when the block area a is filled with the rubber sheet 2, the moving mechanism moves the winder 7 in the arrow direction as shown in FIG. The width-adjusted rubber sheet 2 is attached and embedded. At this time, each time the rubber sheet 2 is wound once, a stitcher is applied to the width direction side end portion e of the rubber sheet 2 in the block area a and the width direction side end portion f of the rubber sheet 2 in the block area b, which abut each other. And both rubber sheets 2 are spliced together. In this way, when the block area b is filled with the rubber sheet 2, the winder 7 is moved in the direction of the arrow as shown in FIG. Paste 2 and fill. As a result, a tread 9 wider than the maximum width W of the rubber sheet 2 is formed on the green case 8.

3 (a) (b) (c) shows a tread 9 of an embodiment in addition to molding a wide and large tire, and each tread 9 is shown in FIG.
In (a), 6 block areas, in FIG. 3 (b), 10 block areas, and in FIG. 3 (c), 6 block areas.
It is divided into individual block areas. The rubber sheet 2 is attached and filled in the block area of each tread 9 in alphabetical order of lowercase letters.

Effects of the Invention As described above, according to the present invention, the existing small calender roll can be used as it is,
A rubber sheet having a uniform gauge can be supplied, and the calender roll can be made inexpensive.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of an apparatus for carrying out the present invention, FIGS. 2 (a) to (c) are cross-sectional explanatory views of a tread for explaining the action, and FIG. 3 (a) to (c) is a sectional view of a tread showing another embodiment. 1 ... Calendar roll 2 ... Rubber sheet, 8 ... Green case 9 ... Tread, 10 ... Space a, b, c ... Block area

Claims (1)

[Claims] 1. A method for forming a large tire by attaching a tread having a width wider than the maximum width of a rubber sheet supplied from a calender roll onto a green case, wherein a space occupied by the tread has a width of the rubber sheet. The method for molding a large tire is characterized in that after dividing into a plurality of block regions narrower than the maximum width, the block regions are sequentially filled with width-adjusted rubber sheets.