JPS6330855B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to improvements in a method and apparatus for manufacturing radial tires.

In the production of radial tires, the following points are required to assemble quality unvulcanized tires.

(1) Assembling the carcass plies that make up the carcass accurately into a cylindrical shape.

(2) Bead cores must be placed accurately on the carcass ply.

(3) Wrap the installed core firmly with carcass ply.

(4) The members that make up the side wall and fan section of the tire must be assembled accurately and firmly.

(5) Assemble the breaker and tread to the carcass accurately and firmly.

In order to meet these demands, conventional
Various methods and devices have been proposed.

One example of this is disclosed in Japanese Patent Publication No. 51-33595, which shows an improvement in that the carcass layer can be reliably prepared on a rigid drum before bead core installation and before expansion. This satisfies requirements 1 and 2 described above.

However, the first problem is that when the installed bead core is wrapped in the ply part extending outside the bead core and brought into close contact in a toroidal shape,
Since there is no support member in the inner part of the toroidal carcass, requirement 3 mentioned above cannot be satisfied.

Furthermore, as a second problem, the above first problem also occurs when assembling the members that constitute the tire sidewall from the bead core portion to the tire shoulder portion. Regarding this second problem, one might think that it would be better to assemble the side wall member in the cylindrical state before inflation, but in that case, the member that becomes the shoulder part of the tire It is significantly elongated during expansion, and the cross-sectional shape changes significantly between when assembled and after expansion. Since the shoulder member is an important member that bridges the difference between the curvature of the carcass at the shoulder of the toroidal carcass and the curvature of the breaker at the end of the breaker, significant changes in shape are undesirable. Since the side wall member must be brought into close contact with the outside of the carcass ply folded around the bead core, the fact that it is assembled in advance over the entire area in a cylindrical state makes cleanup work difficult due to this. will be understood by those skilled in the art.

Furthermore, the following points can be raised as a third problem.

This is a common problem with so-called bead lock type devices in which the lower part of the bead core is expanded and installed when the bead core is installed.

In other words, when assembling the carcass layer of a radial tire, the important thing is to wrap the bead core without disturbing the fiber spacing of the carcass cord, which is manufactured under strict control during the raw material process (specifically, the calender process). , the fibers are arranged as densely as possible in the inner peripheral position of the bead core.

However, in the conventional methods including those described above, first, as shown in FIG. 1a, the carcass layer a is
is made smaller than the inner diameter of the bead core to be wrapped in when assembling it into an annular shape, and after installing the bead core b outside it as shown in Fig. 1b, the first
As shown in Figure c, the carcass layer a below the bead core
The fibers in the carcass layer a prepared at this time are expanded outward to adhere to the inner periphery of the bead core b, but the fiber spacing in the prepared carcass layer a destroys the spacing determined in the raw material process, and When the fiber is brought into close contact with the fiber, the fiber density is reduced.

To give a quantitative example, tire size 11R22.5
In the case of bead core inner diameter...576mm Outer diameter of carcass layer before expansion of bead core installation part...536mm Elongation rate...(576−536)/536≒7.5%, when installing bead core, carcass layer is The fiber spacing determined in the process was changed by more than 7%, which translated into an elongation of approximately 126 mm in circumference, which had a major impact on tire quality.

Therefore, even when the carcass ply is precisely wound on a rigid body, the spacing is not only destroyed when it is beadlocked, but also the uneven expansion of the beadlock portion in the circumferential direction causes the formation of dense and dense areas in the ply cord during gluing. This has a serious drawback in that it triggers disturbances in the cord spacing of the toroidal portion when it is made into a toroidal shape. Therefore, methods such as those disclosed in Japanese Patent Publication No. 49-31549 or Japanese Patent Publication No. 54-26596 have been proposed.

Although these have slightly improved the first and second problems mentioned above, they still do not improve the point that assembly work must be performed on an elastic foundation, and The third problem cannot be addressed at all. Note that various solutions have been proposed for the above-mentioned requirement (5).

On the other hand, the above-mentioned methods are all related to the first stage type manufacturing method and apparatus, but the second stage type manufacturing method and apparatus, that is, after the cylindrical carcass is assembled in the first stage, the second stage type manufacturing method and apparatus are used. Now, it is widely adopted to make this into a toroidal shape and assemble a breaker/tread structure to complete the tire.

This method and device are as described in (1) to (4) above.
Various devices have been put into practice to achieve this requirement. In this case, when installing a bead core in a cylindrical carcass, the ply portions extending on the outside of both bead cores are temporarily moved radially inward. After reducing the size (ply down) and installing the bead core,
The ply portion is expanded radially outward (turned up) to wrap around the bead core, and the inner portions of both bead cores are expanded using an expandable rigid drum, the bead core is installed, and the ply portion of the outer portion of the bead core is expanded. The ply part is turned up to wrap around the bead core, but in the former case, "wrinkles" occur due to the change in circumference when plying down, and in the latter case, the ply is turned up to wrap around the bead core. It was not possible to avoid the occurrence of uneven cord spacing due to the rigid drum.

Furthermore, it is well known that handling problems are inevitable when transporting the cylindrical carcass manufactured in the first stage manufacturing equipment to the second stage manufacturing equipment.

As is clear from the above, conventionally,
The proposed method cannot comprehensively solve the above-mentioned requirements (1) to (5) and the above-mentioned third problem, that is, the disturbance of the ply cord spacing in the carcass ply, especially in the vicinity of the bead core. Nakatsuta.

The present invention has been proposed in view of the above-mentioned points, and its purpose is to provide a bead core that is precisely installed in a precisely assembled carcass layer without the occurrence of wrinkles or uneven cord spacing. Moreover, it is an object of the present invention to provide a method and apparatus for manufacturing a radial tire that can be wrapped tightly and that can accurately and firmly assemble members constituting the side wall and shoulder of the tire.

The present invention expands the carcass layer holding the lower part of the bead core within a closed cylindrical surface provided on the outside, thereby controlling the amount of expansion of the carcass layer in the radial direction to a uniform cylindrical shape. a step of forming a cylindrical rigid surface in the internal space of the cylindrical carcass layer formed in the above step, and assembling the cylindrical carcass layer before forming it into a toroidal shape on this cylindrical rigid surface; , and then forming the tire into a toroidal shape.
When the bead core is precisely placed on the precisely assembled carcass layer and the lower part is gripped, the carcass layer is expanded within the closed cylindrical surface as described above.The same surface prevents the expansion in the radial direction. The carcass ply is regulated to a constant state, but instead it is allowed to expand laterally, and at the end of the expansion, the carcass ply between both bead cores becomes almost cylindrical, so an inner cylinder rigid surface is formed inside it as described above, and then If the carcass ply folding and gluing work around the bead core, as well as the tire sidewall and shoulder member gluing work are carried out with the pressure inside the carcass layer removed, it is possible to work on a rigid body, so the bead core can be wrapped. At the same time, the carcass layer can be firmly wrapped without wrinkles or uneven cord spacing, and the tire sidewall and shoulder members can be firmly assembled. After that, the tire is expanded in a toroidal shape, so deformation of the tire sidewall and shoulder member can be minimized, contributing to quality tire manufacturing.

The present invention also provides a plyformer comprising a center former that can be expanded and contracted, and side formers that are arranged on both sides of the center former and can be expanded and contracted, and that can be moved toward and away from the center former. , a bead lock disposed inside the plyformer that is expandable and retractable and capable of moving toward and away from the centerformer; a shoulder former that can be moved into and out of contact with the former; and a case former that is disposed outside the plyformer and that forms a closed cylindrical surface that can move into and out of contact with each other. This relates to a tire manufacturing device, in which a carcass layer is assembled on a preformer, a bead core is installed, and then the lower part of the carcass layer is gripped by a bead lock to inflate the carcass layer. At this time, since a closed cylindrical surface can be formed by the case former placed outside the plyformer, the expansion of the carcass layer in the radial direction is restricted,
By encouraging lateral expansion, the carcass ply between both bead cores can be expanded into a substantially cylindrical shape. Since a cylindrical rigid surface can be formed on the inside of the inflated carcass layer using the shoulder former, folding and gluing of the carcass ply and gluing of tire side walls and shoulder members on the rigid body can be carried out. This makes it possible to contribute to quality tire manufacturing, and to provide an apparatus suitable for carrying out the radial tire manufacturing method.

Hereinafter, the present invention will be explained based on illustrated embodiments.

FIG. 2 is a sectional view showing the first embodiment, FIG. 3 is a sectional view showing the second embodiment, and FIGS. 4 and 5 to 12 are illustrations of operating states. Here,
In particular, the production of a radial tire having a steel cord carcass layer will be explained as an example.

First, the embodiment shown in Fig. 2 has a center former _A3 that is the basis for assembling the carcass ply,
Side formers A ₁ and A ₂ arranged on both sides
A plyform A is arranged coaxially on the outside of the plyform A, and has an inner circumferential surface having an inner diameter larger than the outer diameter of the plyform A, and is separated into left and right parts at the center. case formers B ₁ and B ₂ , and bead gripping devices D ₁ and D ₂ attached to the outside near the separation part of the same case formers (in addition,
D ₁ and D ₂ are installed alternately on the formers B ₁ and B ₂ , and only D ₁ is shown in Figure 2, but D ₂ is attached to the formers as shown in Figures 5 to 8. Mounted on B ₂ . ), bead holders E ₁ , E ₂ slidably installed inside the case formers B ₁ , B ₂ , and the preformer A
It consists of shoulder formers C ₁ and C ₂ arranged on both sides of center former A ₃ inside the center former, and bead locks F ₁ and F ₂ arranged on both sides of the same shoulder formers C ₁ and C ₂ . In addition to the above-mentioned _{configuration} , the embodiment shown in _FIG . It is equipped with collectors G ₁ and G ₂ .

The specific configuration of each element will be explained below.

Regarding the plyformer A, the center former A ₃ , side formers A ₁ , A ₂ that constitute the preformer A can be expanded and contracted independently or synchronously, and the side formers
A ₁ and A ₂ can be moved toward and away from the center former A ₃ separately or synchronously. At the expansion limit, the center former A ₃ provides a substantially cylindrical rigid surface that matches the inner diameter of the carcass ply, and at the reduction limit, it is sufficiently smaller than the inner diameter of the bead portion of the assembled tire. be done. Also, side formers A ₁ and A ₂ are respectively center formers.
When used in conjunction with the expansion limit state of A ₃ , it provides a substantially cylindrical rigid surface that matches the inner circumferential diameter of the carcass ply, and at the expansion limit, a plurality of fan-shaped The pieces can be made slightly larger than the inner diameter of the bead, and at the limit of reduction, the adjacent fan-shaped pieces are folded overlapping each other as shown in Figure 4 (d), and due to this folding and the magnet described later, the carcass ply becomes fan-shaped. It is adapted to be deformed as shown in FIGS. 4d and 4e by adsorption to the piece.

When using the center former A ₃ and side formers A ₁ and A ₂ as the basis for winding the carcass ply, the outer diameter of the ply former A (i.e., the inner diameter of the carcass ply) is smaller than the inner diameter of the bead core to be installed. It is designed to be equal to or slightly smaller than the carcass ply thickness.

Next, the structure of each former A ₁ , A ₂ , A ₃ will be explained.

The center former A ₃ is composed of a plate 2 fixed on the shaft 1, a plurality of sets of pistons 3 provided on the outer periphery of the circular plate 2, and a magnet 4 embedded in the outer periphery of each piston 3. ing. Preferably, the top portion of the piston 3 is a fan-shaped piece. The piston 3 is expanded radially outward by fluid pressure introduced from the outside of the device to provide a substantially cylindrical surface for winding the carcass ply, and is expanded by a return spring or the like (not shown). When fluid pressure is removed by a known mechanism, it contracts radially inward, at the limit of which the outside diameter of the crown is substantially smaller than the inside diameter of the bead portion of the completed tire.

Furthermore, said shaft 1 coaxially mates with the shaft 5 in its proper position, so that the shafts 1 and 5 are axially movable relative to each other.

The side former A ₁ includes a sleeve 6 mounted coaxially and slidably in the axial direction on the shaft 5, and a disc provided at the end of the sleeve 6 on the side of the center former A ₃ . 7, a plurality of fan-shaped pieces 8 attached to the same disc 7 so as to be expandable and contractable in the radial direction,
Although many known mechanisms can be adopted as the drive mechanism, here, as an example, a slide 9 that slides on the sleeve 6, the slide 9 and each sector piece 8 are used. This figure is constructed of a plurality of links 10 that communicate with each other, and a fluid pressure cylinder 11 that is connected to the slide 9 at one end and the disc 7 at the other end. Although not shown, a magnet is embedded in the outer peripheral surface of the fan-shaped piece 8.
The magnet may be permanent or electromagnetic so that it is deenergized upon axial movement of the sector.

Further, the lengths of the links 10 provided in each pair on adjacent fan-shaped pieces 8 can be changed, or the coordinates of their connecting parts can be changed. Piece 8
moves inward in the radial direction, and adjacent fans are moved synchronously but with a time difference due to links of different lengths (or links with different coordinates). However, the outer diameter of each fan-shaped piece when used for winding carcass ply is designed to be the same radius.

Furthermore, by shortening the cylinder 11, the fan-shaped piece 8
is expanded further outward from the position shown in FIG. 2, and at this time also, the adjacent fan-shaped pieces 8 are expanded synchronously but with a time difference, and at the expansion limit, preferably It is designed to stay within the core bar area of the bead core. In this case, the outer positions of the adjacent fan-shaped pieces 8 will be slightly different from each other, but this will not cause any problem in operation as will be described later.

Further, the sleeve 6 is connected to a hydraulic cylinder 12 mounted at a suitable position on the shaft 5 or the sleeve 14. Note that the sleeves 6 and 14 are
It is possible to slide on the shaft 5 in the axial direction, but it cannot rotate relative to each other, and it rotates as the shaft 5 rotates, and the shaft 5 and shaft 1 are driven from the shaft 1 side when mating. Any known connection means may be employed.

Therefore, the axial position of the side former A ₁ can be arbitrarily controlled by the fluid pressure cylinder 12, and furthermore, the outer diameter of the fan-shaped piece 8 can be arbitrarily controlled at each position. and axes 1 and 5
It can be rotated along with the rotation of . Note that the side former A ₂ has the same configuration as the side former A ₁ except that it is mounted on the shaft 1 side, so a description thereof will be omitted. Case former B ₁ ,
B ₂ , bead gripping devices D ₁ , D ₂ , and bead holders E ₁ , E ₂ , the case formers B ₁ , B ₂ are aligned with the center line of the tire to be assembled (this is not an absolute condition) and are aligned to the left and right. The case formers B ₁ , B ₂ each constitute an outwardly coaxial and substantially continuous cylindrical inner surface of the former B 1 , B 2 at the time of engagement, and the cylindrical inner surface thereof has an effective length sufficient to expand the carcass ply into a cylindrical shape. Further, the diameter of the inner surface of the cylinder is made slightly larger than the diameter obtained by adding the thickness of the carcass ply to the outer diameter at the expansion limit of shoulder formers C ₁ and C ₂ to be described later.

Case former B ₁ is preformer A
The hydraulic cylinder 15 is mounted coaxially on the frame and is connected to a fluid pressure cylinder 15 fixedly attached to a pedestal portion (not shown).

In addition, on the outside of the center of case former B ₁ ,
A bead gripping device _D1 is installed, which is composed of a plurality of arms 16 that are swingably mounted, a magnet 17 that is mounted on the arms 16, and a hydraulic cylinder 18 that is connected to the arms 16. There is. Furthermore, inside the case former B ₁ ,
Consisting of a fluid pressure cylinder 19 fixed to the end opposite to the center of the case former _B1 , and a slide 20 connected to the rod part of the cylinder and sliding on the inner cylindrical surface of the former _B1 as a guide. A bead holder _E1 is provided.

Note that the slide 20 has a convenient shape on which to place the beads to be installed.

In addition, the case former B ₂ , the bead gripping device D ₂ installed on the outside of the case former B ₂ , and the bead holder E ₂ installed on the inside of the case former B ₂ are connected to the case former B ₁ , respectively. , bead gripping device D ₁ , and bead holder E _{1 ;}
The mounting position of D ₂ is shifted in the circumferential direction so that case formers B ₁ and B ₂ do not collide when mating.

Regarding the shoulder formers C ₁ and C ₂ , the shoulder formers C ₁ and C ₂ have plyformers A ₁ and A ₂ sufficiently separated from the center former A ₃ and are formed of plyformer A. The carcass ply is expanded and the case former B ₁ ,
When it is formed into a cylindrical shape inside B ₂ , it is expanded, and although the left and right sides are separated by the expansion limit, it constitutes a substantial cylindrical body having the same outer diameter, and preferably the outer diameter of the cylindrical body is the same. is the shape and size near the shoulder of a type of drum called a high crown drum used in the first stage equipment of the known two-stage manufacturing method, and at the expansion limit, the case former B ₁ ,
It is smaller than the inner diameter of the inner cylindrical surface of _B2 by taking into consideration the thickness of the carcass ply and a small margin.

The structure will be specifically explained below with reference to the drawings.

Note that shoulder formers C ₁ and C ₂ have similar configurations, and in Figure 2, each adjacent shoulder segment is shown divided into a right-hand side and a left-hand side for ease of understanding. . The shoulder former C ₁ has a nut 22 engaged with a screw 21 a of a threaded rod 21 mounted inside the shaft 1.
a, a pin 24' fixed to the nut and protruding from the axial longitudinal notch hole of the shaft 1; a sleeve 23 connected to the pin 24' and slidably mounted on the shaft 1; A disc 24 is provided at the appropriate location, a plurality of fan-shaped bodies 25a and 25b are mounted to guide grooves radially arranged on the disc 24 so as to be movable in the radial direction, and the fan-shaped bodies 25a, 25b
It consists of two driving means. Note that although the description here is about the former _C1 , the fan-shaped body 25b is illustrated on the former _C2 side as described above.

Further, the guide groove of the fan-shaped body 25b is slightly inclined as shown in the figure, and the guide groove of the fan-shaped body 25a is not inclined at all, or the guide groove of the fan-shaped body 25a is tilted slightly.
It is not as inclined as the groove in b, but it is slightly inclined. By tilting the guide groove in this way, each fan-shaped body 25
When a and 25b move inward, it is possible to generate a difference in the amount of movement in the axial direction between the side portions of each fan-shaped body, and the amount of movement in the radial direction can be reduced.

Further, many known methods can be adopted as the driving means for moving the fan-shaped bodies 25a, 25b along the guide grooves, but one example is a driving means that is installed on the sleeve 23 coaxially with respect to the shaft 1. Rotating body 2
6. It is composed of a plurality of links 27 connecting each of the fan-shaped bodies 25a, 25b and the rotating body 26, and a hydraulic cylinder 28 whose one end is connected to the sleeve 23 and the other end is connected to the rotating body 26. In addition, fan-shaped body 2
When the guide groove 5a is not inclined with respect to the axis 1, there is no need to consider the connecting portion between the link 27 and the fan-shaped body 25a against movement in the axial direction, but when the guide groove is inclined as in the case of the fan-shaped body 25b, , it is necessary to allow free movement in the axial direction at the connecting portion between the link 27 and the fan-shaped body 25b as well as the swinging of the link 27,
Also, the links used in the fan-shaped body 25a and the fan-shaped body 2
It is also necessary to consider changing the length of the links used in 5b.

Further, a driving source for the fluid pressure cylinder 28 is introduced from outside the apparatus using a known method.

Furthermore, in the case of the illustrated example, the fan-shaped bodies 25a, 25b of the shoulder former _C1 are
However, separate rotating bodies for the fan-shaped bodies 25a and 25b may be provided and driven by independent drive devices.

With the above structure, the fan-shaped bodies 25a and 25b of the shoulder former _C1 expand outward in the radial direction with a time difference given by the rotation of the rotating body 26,
Each fan-shaped body 25a, 25 at its expansion limit
b can constitute a substantial cylindrical body both in the axial direction and in the outer radial direction.

In addition, the shoulder former C ₂ is also a former.
Although it has the same structure as _C1 , it is driven by a nut 22b that is engaged with a screw 21b, and these screws 21a and 21b are reverse threaded.

Therefore, by rotating the threaded rod 21, the shoulder formers C ₁ and C ₂ are brought into contact with and separated from each other, and can be expanded and contracted at arbitrary positions.

Regarding the beadlocks F ₁ and F ₂ , the beadlocks F ₁ and F ₂ are respectively arranged inside the plyformer A and on the sides of the shoulder formers C ₁ and C ₂ , and the side formers A ₁ and A ₂ are located at the center. When the bead locks F ₁ and F ₂ are positioned at the lower part of the bead core, which is spaced away from the former A ₃ and placed in place, they expand radially outward to bond the carcass ply to the inner circumferential surface of the bead core, and
The space between the bead locks on both sides is kept in a sealed state, and functions as a sealing device when inflating the carcass as necessary.

The structure will be specifically explained below with reference to the drawings.

The bead lock F ₁ is slidable on the shaft 5, and
It consists of a sleeve 14 and a disk 29 that rotate together, an elastic body 30 housed in a groove formed on the outer periphery of the disk 29, and a fluid pressure cylinder 31 whose rod portion is fixed to the disk 29.

The elastic body 30 is expanded by fluid pressure introduced from outside the device, and is contracted by its own elastic force when the pressure is removed, and the cylinder 31 is attached to the disc 7 of the side former _A1 . Fixed.

Further, a spacing fine adjustment device 32 is provided between the tip of the sleeve 14 and the sleeve 23 of the shoulder former _C1 . This interval fine adjustment device 3
2, the shoulder former expands, increases the gap during contraction, and narrows the gap after expansion is completed, so that the bead core portion gripped by the elastic body 30 is expanded into a cylindrical shape. It acts to allow you to approach the shoulder former a little closer.

Note that this adjustment device may be directly operated by an electromagnetic cylinder, a fluid pressure cylinder, etc., or the sleeves 14, 2 may be operated using these as a driving source.
A known mechanism such as inserting and removing a spacer between 3 and 3 may be employed.

According to the above structure, the bead lock F ₁ can be moved along with the axial movement of the side former A ₁ by closing both air chambers of the cylinder 31, and the state in which fluid is continuously supplied so that the rod protrudes is maintained. If side former A ₁ is moved to the side, it can be left on the shoulder former C ₁ side, or side former A ₁ will be stopped on the side and the bead lock F will be moved by cylinder 31. If shoulder former C ₁ is moved on its axis while shoulder former C 1 is being pressed against shoulder former C ₁ , bead lock _{F 1 will} move in both the left and right directions following the movement of shoulder former C ₁ . Furthermore, the relative distance when the shoulder former C ₁ is pressed against the shoulder former C 1 can be changed as necessary by the distance adjusting device 32 .

The above is the configuration of the first embodiment shown in FIG. 2, and the second embodiment shown in FIG. It has collectors G ₁ and G ₂ .

Collectors G ₁ and G ₂ are the case formers mentioned above.
An annular body located outside B ₁ and B ₂ and coaxially disposed with any of the shafts 1 or 5, case formers B ₁ and B ₂ , and plyformer A, and capable of moving toward and away from the shaft in the axial direction. 50 and a fluid pressure cylinder 51.

The approach limit of the annular body 50 to the center of the tire is determined by the hydraulic cylinder 15 and the cylinder 51, and the left and right annular bodies 50 are positioned symmetrically with respect to the center of the tire to be manufactured. Therefore, when the carcass is made toroidal and expanded to a greater extent than the annular body 50, if the toroidal carcass is biased by pressing the annular body 50 from both sides, it is corrected and the breaker/tread structure is moved to the center position of the carcass. This brings about the effect of being able to bond correctly.

Note that the fluid pressure cylinder described in the above structural description is not limited to this, and may be any shaft drive device, and in some cases, for example, a motor and a threaded rod may be integrated to have an appearance similar to a fluid pressure cylinder. may be adopted.

Next, manufacturing of tires using the above-mentioned apparatus will be specifically explained.

First, when the shafts 1 and 5 are moved relatively apart and the bead core b to be assembled is installed in the bead holders E ₁ and E ₂ , each component is in the state shown in FIG. 5. That is, the side formers A ₁ and A ₂ of the plyformer A are positioned outside the bead locks F ₁ and F ₂ , and the fan-shaped piece 8 of each side former is folded in the radial direction to reduce its outer diameter. Bead holder E ₁ , E ₂ slide 20
It is said that the state is unable to block the progress of the

Furthermore, the center former A ₃ of the plyformer A is retracted radially inward to reduce its outer diameter, and the bead locks F ₁ and F ₂ are retracted radially inward, and further The shoulder formers C ₁ and C ₂ are folded at a position closer to the center former A ₃ of the ply former A to reduce their outer diameters. In the above state, case formers B ₁ and B ₂ and bead holders E ₁ and E ₂ are at their most advanced positions.

At this time, the arms 16 of the bead gripping devices D ₁ and D ₂ are expanded to receive the bead cores, and the operator places each bead core b on the bead core installation site of each slide 20. Subsequently, the slide 20 is moved backward, and the bead core b is housed inside the case formers B ₁ and B ₂ , and the case formers B ₁ and B ₂ are also moved back to a position where they do not obstruct material supply. .

Next, as shown in FIG. 6, the shafts 1 and 5 are connected, and the fan-shaped pieces 8 of the side formers A ₁ and A ₂ are expanded to have the carcass ply winding diameter, and the side formers A ₁ , A ₂ approaches. At this time, center former A ₃ is expanded, and the outer diameter of the center former is used as the carcass ply winding diameter.
At the forward limit of A ₁ and A ₂ , a plyformer A is formed which is integrated with the center former A ₃ .
By rotating the shafts 1 and 5, the former A is rotated synchronously.

Here, the chief, inner liner, carcass ply, etc. are wound onto the ply former A in a predetermined procedure from a known material supply device (not shown).

The carcass ply a containing steel cord is attracted by the magnet of the center former _A3 and the magnets of the side formers _A1 and _A2 .

In this way, the carcass ply a is
It can also be prepared on a rigid body as shown in Fig.

Next, as shown in FIGS. 7 and 4b, the outer diameters of the side formers A ₁ and A ₂ are made slightly smaller (however, the outer diameters of the side formers A 1 and A 2 are made so as not to contact the outer diameter portions of the elastic bodies 30 of the bead locks F ₁ and F ₂ . ,) has been set back.

At this time, the speeds of both side formers A ₁ and A ₂ are the same, and it is preferable to do it synchronously. Also, the magnets of side formers A ₁ and A ₂ are electromagnetic, and when the formers retreat, the attraction force is applied. It is preferable to remove.

The carcass layer a formed into a cylindrical shape on the plyformer A is supported at its center by the centerformer _A3 , is attracted by a magnet, and is left in the position at the time of winding.

On the other hand, when both side formers A ₁ , A ₂ are located outside the bead locks F ₁ , F _{2 , the side formers A 1 ,} A ₂ stop moving back, and each fan-shaped piece 8 folds inward in the radial direction. At this time, by applying the magnets of the side formers A ₁ and A ₂ , the end of the carcass layer a is attracted to the fan-shaped piece 8 as shown in the figure and is elastically deformed. The deformed state of the end portion of the carcass layer is as shown in FIGS. 4d and 4e, and the outer diameter of the envelope at the bead installation portion is smaller than the inner diameter of the bead core.

Next, the case formers B ₁ and B ₂ are advanced, and the slide 20 is advanced, and the arms 16 of the bead gripping devices D ₁ and D ₂ are rotated to attract the advancing bead core b with the magnet 17. , when the bead core b is attracted, the slide 20 retreats.

In this way, the bead core b on the slide 20 is transferred to the bead gripping devices D ₁ and D ₂ . Naturally, the stopping positions of the case formers B ₁ and B ₂ are controlled so that the delivered bead core b is correctly positioned on the prepared carcass layer a.

Then, as shown in FIGS. 8 and 4c, the attraction of the magnets of the fan-shaped pieces 8 of the side formers A ₁ and A ₂ is released, and the side formers A ₁ and A ₂ are further retreated in the folded state. do.

At the same time, shoulder formers C ₁ , C ₂ and bead locks F ₁ , F ₂ are synchronously moved outward and stopped at a fixed position so that bead locks F ₁ , F ₂ are located below bead core b.

Beadlock F ₁ and F ₂ are shoulder forms.
Moves with support from C ₁ and C ₂ .

The bead locks F ₁ and F ₂ expand their outer diameters and adhere the carcass layer a to the inner surface of the bead core b. After the adhesion is completed, the arms 16 of the bead gripping devices D ₁ and D ₂ rotate to grip the bead core b. unlock.

The left side of FIG. 8 shows the state in which the bead core is released, and the right side of FIG. 8 shows the state in which the bead core is bonded. After the rotation of each arm 16 is completed, the case formers B ₁ and B ₂ move forward to form a closed cylindrical surface outside the carcass layer a where the bead core b is installed. The closed cylindrical surface formed by the case formers B ₁ and B ₂ is shown in dashed lines in FIG.

Incidentally, the retraction of the side formers A ₁ and A ₂ prior to the above-mentioned movement of the bead locks F ₁ and F ₂ to their regular positions can also be carried out as follows.

While the bead core is held in place, the carcass layer is adhered to the inner surface of the bead core by expanding the side formers A ₁ and A ₂ with the magnets released, folding the carcass layer a little smaller and retracting it, and then setting the bead lock. You may re-glue the lower part of the peed core in position.

Next, as shown in FIG. 9, beadlock F ₁ ,
By crimping the bead core b with F ₂ and keeping the inside of the carcass layer a airtight while introducing pressurized air from the outside and moving both bead locks synchronously inward, the carcass layer a will form a case foam. _B1 ,
It expands under external regulation by B ₂ .

The left side of FIG. 9 shows the initial stage of expansion, and the right side shows near the end of expansion.

The synchronous width shifting of the bead locks F ₁ and F ₂ is performed when the shoulder formers C ₁ and C 2 perform a synchronous width shifting movement while the bead locks are pressed against the shoulder formers C ₁ and _{C 2 by} the cylinder 31. It is achieved by doing.

Next, as shown in FIG. 10, the shoulder formers C ₁ and C ₂ are expanded within the cylindrical carcass layer in the space between the center former A ₃ and the bead locks F ₁ and F ₂ until they reach the expansion limit. Form a cylinder.

Depending on the shape of the bead core installation portions of the shoulder formers C ₁ and C ₂ , it may be necessary to move both bead locks slightly toward the shoulder former after the shoulder formers are expanded. In such a case, after the shoulder former expansion is completed, the shoulder formr C ₁ ,
By changing the relative distance between C ₂ and bead locks F ₁ and F ₂ , the bead lock can be pushed toward the shoulder former.

Next, as shown in FIG. 11, the pressure air inside the carcass layer is removed and the shoulder formers C ₁ and C ₂ are removed.
Then, the bead locks F ₁ and F ₂ are integrally moved slightly outward.

The above action isolates the carcass layer from the inner surfaces of the case formers B ₁ and B ₂ .

Thereafter, the case formers B ₁ and B ₂ are retreated outward, and the carcass layer at the outer end of the bead core is folded back and crimped using a known crimping wheel so as to wrap around the bead core.

At this time, if necessary, the bead lock may be released, the bead lock may be temporarily retracted to the outside, and the lower part of the bead core may be crimped by the crimping wheel.

Further, necessary parts such as the side wall members of the tire are wrapped around the outside of the folded carcass layer in a predetermined manner and pressure-bonded.

After completing the above crimping work, as shown in Fig. 12, the lower part of the bead core is crimped and supported by bead locks F ₁ , F ₂ , an airtight chamber is again formed, and while supplying pressurized air, shoulder formers C ₁ , C ₂ , Beadlock F ₁ ,
By integrally and synchronously moving F ₂ inward, the cylindrical carcass layer is made into a toroidal shape as shown.

If necessary, the fan-shaped pieces 8 of the side formers A ₁ and A ₂ that were in a standby state may be expanded to a size that touches the bead core portion, and the sides of both bead cores may be pressed to form a toroidal shape. In this state, the carcass layer and the breaker tread structure are attached by placing the preformed breaker tread structure in the center of the carcass and further forming it into a toroidal shape using known means. After bonding, the transport mechanism of the structure is moved backwards, and the final pressure bond is performed using a pressure bonding wheel to complete the tire.

After the tire is completed, the bead lock, shoulder former, side former, and center former are placed in the state shown in Figure 5 at the start of the process.

The above is an explanation of the operation according to the first embodiment, but
In the case of the second embodiment, only the step of forming it into a toroidal shape is different.

That is, in the process of making it into a toroidal shape, the case formers B ₁ and B ₂ and the collector G ₁ on the same former,
After correcting the deviation of the carcass layer when forming it into a toroidal shape by stopping G ₂ at a fixed position near the center of the carcass, the breaker/tread structure is assembled.

The operating states of collectors G ₁ and G ₂ are shown by dashed lines in FIG. 12 and can be easily understood.

As is clear from the detailed explanation above, according to the above embodiment, the above-mentioned requirements (1) to (5) for obtaining quality can be satisfied, and at the same time the above-mentioned first and second requirements can be satisfied. In practical terms, the third problem can be completely solved, and an extremely valuable effect can be produced.

[Brief explanation of drawings]

Figures 1a to d are diagrams showing a part of the conventional tire manufacturing process step by step, Figure 2 is a sectional view showing one embodiment of the present invention, and Figure 3 is another embodiment of the present invention. A sectional view showing an example, FIGS. 4a to 4e are diagrams showing the state of a part of the tire manufacturing process step by step, and FIGS. 5 to 12 are diagrams showing the operating state of each element in the tire manufacturing process. . a: carcass layer, b: bead core, A: pliformer, A ₁ , A ₂ : side former, B ₁ ,
B ₂ : Case former, C ₁ , C ₂ : Shoulder former, F ₁ , F ₂ : Bead lock.

Claims (1)

[Claims] 1. By expanding the carcass layer holding the lower part of the bead core within a closed cylindrical surface provided on the outside thereof, the amount of expansion of the carcass layer in the radial direction is regulated to be uniform. a step of forming it into a cylindrical shape;
A step of forming a cylindrical rigid surface in the internal space of the cylindrical carcass layer formed by the above process, and assembling the cylindrical carcass layer before forming it into a toroidal shape on this cylindrical rigid surface; A radial tire manufacturing method characterized by comprising a step of forming a radial tire. 2. A plyformer consisting of an expandable and retractable center former, and side formers arranged on both sides of the center former that are expandable and retractable and that can be moved toward and away from the center former; beadlocks disposed inside the plyformer, expandable and retractable, and reciprocal with respect to the center former; A radial tire manufacturing apparatus comprising: a shoulder former that can be moved toward and away from the plyformer; and a case former that is disposed outside the plyformer and that can be moved toward and away from each other and forms a closed cylindrical surface.