JPS61172724A - Forming of tire and device thereof - Google Patents

Abstract

PURPOSE:To easily and accurately manufacture a tire with a plurality of bead cores with no shifting and tapered turning-up of carcass plies by a method wherein a plurality of pairs of radially shiftable bead locking bodies are provided on a drum main body. CONSTITUTION:Firstly, a first ply 61 is pasted onto a drum main body 2. Secondly, first bead cores 57 are set at predetermined positions. Thirdly, first bead locking bodies 10 are shifted radially so as to hold said cores 57. Fourthly, bladders 50 are inflated in order to turn up the end parts of the ply. After that, similarly a second ply 62 is pasted and second bead cores 58 are held with second bead locking bodies 13 in order to manufacture a tire with a plurality of bead cores 57 and 58 by turning up the end of the second ply. Thus, the shifting and tapered turning-up of carcass plies becomes unnecessary, resulting in facilitating the forming work of the tire. In addition, because the bead core is held with the bead locking body, the satisfactory positioning accuracy is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method and apparatus for forming tires having multiple bead cores.

Conventionally, when molding a tire having multiple bead cores, such as a double bead tire, first, a first carcass ply is molded into a cylindrical shape using a band molding machine, and then,
This first carcass ply is transferred from the band forming machine to the forming drum by a transfer device. At this time, the first
Since the axial length of the carcass ply is longer than the axial length of the forming drum, both axial ends of the first carcass ply overhang from both axial ends of the forming drum. Next, one hang part is folded inward in the radial direction into one side of the first carcass ply using a plurality of fins.Next, a pair of first bead cores are placed at predetermined positions around both overhang parts by a bead setter. After transporting to
The overhang portion is folded back approximately 180 degrees by the bladder, and the first bead core is wrapped by the overhang portion. Next, the cylindrical second carcass ply formed by the band forming machine is transferred to the forming drum to which the first carcass ply is attached in the same manner as described above.
Next, after folding the overhang part, move the second bead core to a predetermined position around the overhang part of the second carcass ply, then fold back the overhang part in the same manner as described above and fold the second bead core over the second bead core. Wrapped by the hang part.

However, the above-mentioned tire forming method requires a step of transferring the first carcass ply and the second carcass ply from the band forming machine to the forming drum and a step of folding the overhang part so that it becomes tapered. Therefore, there is a problem that work efficiency is low. Another problem is that a band forming machine and a transfer device are required for band forming and transfer. Furthermore, a first layer is placed around the overhang part, where the dimensional accuracy cannot be very high as a result of the tapered folding. Since the second bead core is arranged, there is also a problem that the positioning accuracy of the bead core is low.

(-) This invention solves the conventional problems of low work efficiency, the need for large-scale equipment, and low accuracy in positioning the bead core.

These problems are caused by the process of transferring the first bead core to a predetermined position around the first ply after attaching the first ply to the drum body, and the process of moving the first bead lock body radially outward. a step of moving the first bead core from the inner peripheral side through the first ply, a step of folding back the first ply on the axially outer side of the first bead core to wrap around the first bead core, and a step of After attaching the second ply to the second ply, attach the second bead core to the
a step of transferring the second bead core to a predetermined position around the ply; a step of moving the second bead lock body radially outward to hold the second bead core from the inner peripheral side via the second ply; Fold back the second ply on the outside in the direction
By the method including the step of wrapping the bead core,
Further, the drum body is rotatable and has a ply attached to its outer circumference, a plurality of pairs of bead lock bodies are installed at both axial ends of the drum body and are movable in the radial direction, and are movable in the radial direction. This problem can be solved by a device including a pair of supply means for respectively supplying the bead cores to the outside of the bead lock body in the radial direction, and a pair of bladders for respectively returning the plies axially outward from the bead cores.

1” First, after pasting the first braai on the outer periphery of the drum body,
The first bead core is transferred around the first ply to a predetermined position radially outward of the first beadlock body by the pair of supply means. Next, the first beadlock body is moved radially outward. As a result, the annular portion of the first ply that is inscribed in the first bead lock body expands in diameter and inscribed in the first bead core. As a result, the first bead core is held from the inner peripheral side by the first bead lock body through the first ply, and then the first ply on the axially outer side of the first bead core is folded back by the pair of bladders, and this folded back Next, after pasting a second ply onto the first ply, the second bead core is wrapped at a predetermined position around the second ply outside the first bead core in the axial direction. Next, the second bead lock body is moved radially outward to hold the second bead core from the inner peripheral side via the second ply, and then The ply is folded back by the bladder to wrap around the second bead core.

In this way, a double bead tire is formed,
For example, when molding a triple bead tire, following the above-mentioned operations, all you have to do is attach the ply, supply the bead core, move the beadlock body, and fold back the braai in the same way as described above. , the process of transferring and folding into a tapered shape is no longer necessary, improving work efficiency.

Further, there is no need to use a special device, and since the bead core is also held by the bead lock body, the positioning accuracy is improved.

1j Hereinafter, one embodiment of the present invention will be described based on the drawings.

In FIG. 1, l is a forming drum, and this forming drum l has a drum body 2. In FIG. The drum body 2 has a cylindrical outer shaft 3 that is driven and rotated by a motor (not shown), and a screw shaft 4 that can rotate integrally with the outer shaft 3 or separately is housed within the outer shaft 3. On the outer periphery of the screw shaft 4, threads are formed in opposite directions with the axial center as the boundary.

Further, slits 5 extending in the axial direction are formed at both ends of the outer shaft 3, and a slide block 7 having a nut portion 6 screwed into the thread of the screw shaft 4 passes through each slit 5. The slide block 7 reciprocates in the axial direction of the drum body 2 while being guided by the slit 5 by individual rotation of the screw shaft 4. A plurality of first sliders 8 are housed in each slide blow 2 7 so as to be movable in the radial direction, and a first block 9 is fixed to the outer end of each first slider 8 in the radial direction. The aforementioned first slider 8 and first block 9 constitute a first beadlock body 10 as a whole, and these pair of first beadlock bodies lO
are installed at both ends of the drum body 2 in the axial direction. 1st
A plurality of second sliders 11 are housed in the slide block 7 axially outside the slider 8 so as to be movable in the radial direction, and a second block 12 is fixed to the outer end of each second slider 11 in the radial direction.

The aforementioned second slider 11. The second block 12 as a whole constitutes a second beadlock body 13 that is axially separated from the first beadlock body lO, and these pair of second beadlock bodies 13 are attached to both ends of the drum body 2 in the axial direction. is set up. Furthermore, first and second cylinder chambers 21 and 22 are formed in each slide block 7, and these first and second cylinder chambers 21 and 22 are formed inside each slide block 7.
．． The second cylinder chamber 21.22 is connected to the axially movable first cylinder chamber 21.22.
, is divided into an inner chamber 25.28 and an outer chamber 27.28 by the axially outer end wall of the second piston 23.24. The inner and outer chambers 25.2B and 27.28 are connected to ports A, B, C, and D by passages 29.30.31.32, respectively. A roller 37.3B provided at one end of the first and second links 35.36 bent in a dogleg shape is accommodated in the groove 33.34 formed in the first and second pistons 23.24. . The center portions of the first and second links 35 and 38 are rotatably supported by the slide block 7 via pins 39 and 40, and a pin 4
1.42 is slidably inserted into a groove 43.44 formed in the first and second sliders 8.11. A pair of cylindrical bladders 50 are provided at the outer station of the slide block 7.
is provided. Each bladder 50 has a plate-shaped flat part 51 on the inner end in the axial direction, and mounting rings 5 on both ends on the outer end in the axial direction.
The expansion part 53 which is closed by 2 and becomes a tube shape,
have. A cylindrical center deck 54 is attached to the axial center of the outer shaft 3 via a deck support 55 extending in the radial direction. Also, 5B is a forming drum l
The bead setters 56 serve as a pair of supply means that can move in the axial direction of the
．． i2 bead core 57.58 to first beadlock body 1O
113 at predetermined positions radially outward.

A pair of cans 59 are movable in the axial direction of the forming drum 1, and each can 59 pushes the expanded portion 53 of the expanded bladder 50 inward in the axial direction.

Next, the operation of one embodiment of the present invention will be explained.

First, a belt-shaped first ply 61 consisting of an inner liner, carcass ply, etc. is supplied to the rotating drum body 2, and the first ply 61 is attached to the outer periphery of the drum body 2 as shown in FIG. 2(a). Pasting is done by 8 steps of forming into a cylindrical shape.
By the bead setter 56: Transfer the fSl bead core 57 around the first ply 61 to a predetermined position radially outward of the first beadlock body 10. Next, air is supplied from the C boat to the outer chamber 27 through the passage 31. Then, the first piston 23 is moved axially inward. As a result, the first link 35 rotates clockwise, and the first beadlock body lO
protrudes radially outward as shown in FIG. 2(b).

The first beadlock body 1O is formed by annularly expanding a portion of the flat portion 51 and the Nll1 ply 61 located radially outward of the first beadlock body 10.

The first bead core 57 is held from the inner assembly side via the first ply 61. At this time, since the rubber located within the annular bulge of the first ply 61 expands, the cord arrangement within the annular bulge is likely to be disturbed.

In recent years, it has become possible to arrange the cords on the ply extremely uniformly and accurately, so that disturbances in the cord arrangement can be suppressed to a practically negligible level, causing no problems.

Next, air is supplied into the inflatable parts 53 of both bladders 50 to inflate the inflatable parts 53.Next, the can 53 is moved axially inward and the inflatable parts 53 are pushed inward in the axial direction. As a result, the first ply 81 on the axially outer side of the first bead core 57 is folded back approximately 180 degrees, and
is surrounded by the first ply B1, and the expansion part 5
3 contracts and the can 59 returns to its original state.Next, in the same manner as described above, a second ply 62 made of carcass ply etc. is attached to the outer periphery of the first ply 61 as shown in FIG. 2(C). Next, the second bead core 5B is transferred to a predetermined position radially outward of the second beadlock body 13 around the second ply 62 by the bead setter 58. Next, the second bead core 5B is transferred from the D port to the outer chamber through the passage 32. When air is supplied to 28 and the second piston 24 is moved axially inward as shown in FIG. 2(d), the second beadlock body 1
3 protrudes outward in the radial direction due to the rotation of the second link 3B. As a result, the second beadlock body 13
Then, a part of the second ply B2 is bulged in an annular shape and the second bead core 58 is held from the inner peripheral side via the second ply 82. After inflating the inflation part 53 of the bladder 50, the cap 75
9 pushes the expansion part 53 inward in the axial direction. As a result, the second ply 62 on the outside in the axial direction from the second bead core 5B is folded back, and the PiS2 bead core 58 is surrounded by the second ply 82 and expands to the zero order. As the part 53 contracts, the can 59 returns to its original position.Next, only the screw shaft 4 is rotated independently, and the two slide blocks 7 are moved closer to each other as shown in FIG. 2(e). , a predetermined high temperature and high pressure fluid is injected into the first ply 81.82 to deform the first ply 61.62 into a toroidal shape.

The above explanation has been made for the case of forming a double bead tire, but when forming a triple bead tire, it is sufficient to attach a ply on top of the ply and then wrap the bead core with the ply. In this case, bead lock is used. Three pairs of bodies are required.

19ΔL9 As described above, according to the present invention, the steps of transferring and folding into a tapered shape are not necessary, and work efficiency is improved. Further, there is no need to use a special device, and since the bead core is also held by the bead lock body, the positioning accuracy is improved.

[Brief explanation of drawings]

FIG. 1 is a sectional view of a main part showing an embodiment of the invention, and FIGS. 2(a) to 2(e) are explanatory diagrams explaining the invention in detail. 2...Drum body! O...First beadlock body 13...Second beadlock body 50...Bladder 5B...Supplying means (bead setter) 57...First
Bead core 58...second bead core

Claims (2)

[Claims] (1) After attaching the first ply to the drum body, transferring the first bead core to a predetermined position around the first ply, and moving the first bead lock body radially outward to attach the first bead core to the drum body. a step of holding the first ply from the inner peripheral side via the first ply, a step of folding back the first ply on the axially outer side of the first bead core to wrap the first bead core, and pasting a second ply on the first ply. and then moving the second bead core axially outward from the first bead core to a predetermined position around the second ply, and moving the second beadlock body radially outward to transfer the second bead core to the second ply. A method for forming a tire, comprising the steps of: holding the ply from the inner circumferential side through the ply, and folding back a second ply located axially outward from the second bead core to wrap the second ply around the second bead core. (2) A drum body that is rotatable and has a ply attached to its outer periphery, a plurality of pairs of bead lock bodies that are installed axially apart from each other at both axial ends of the drum body and are movable in the radial direction; A tire forming device comprising: a pair of supply means for respectively supplying bead cores around the periphery and radially outward of a bead lock body; and a pair of bladders for respectively folding back plies axially outward from the bead cores.