JPH06210762A - Immobilization of untreated case for tire and its device - Google Patents

Abstract

PURPOSE:To eliminate defective centering during the setting of an untreated case and prevent the foot part of the untreated case from becoming deformed by supporting the untreated case using a diametrally expanded inner support, and pressing the beads part of the untreated case to the inner support by a diametrally expanded outer support and immobilizing the beads part. CONSTITUTION:If air is supplied into the cavity 14 of an air cylinder 13 through an air passage 40, a piston 15 expands with a piston 16. An inner support 25 and an outer support 30 are diametrally expanded through roller followers 26, 31. The tapered surface 18a of a cam 18 becomes a sharper slope. The outer support 30 shows a faster diameter expansion speed, so that a cover member 36 first comes in contact with beads part 2 of an untreated case 1 along a peripheral surface 30b which inclines toward the inner part of the outer support 30. Then the beads part 2 is pressed against the flange 25e of the later diameterally expanded inner support 25 through a rubber member 35 to set the beads part 2 to a specified position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for fixing a green case in a tire molding process.

[0002]

2. Description of the Related Art A raw case for a tire molded through a first molding process has bead portions formed on the left and right edges of an annular band, and the bead portion is formed when molding the raw case by a second molding machine. The raw case is fixed to the molding drum by supporting it.

In the second molding step, since the bead portion is supported and the raw case is expanded by applying an internal pressure, it is necessary to secure an air seal at the support portion and to surely perform centering. Therefore, conventionally, the left and right supports that support the left and right bead portions of the raw case support the bead portions from the inside and expand the legs to the outside to widen the foot width.

[0004]

[Problems to be solved] Since a rubber material is used for the portion where the support comes into contact with the bead portion to perform air sealing, when the rubber material for air sealing is deformed evenly in the left and right direction by the action of widening the foot width. However, there is a risk of causing centering failure. Also, to widen the legs,
The bead is easily deformed because it is pulled when the low pressure is locked.

On the other hand, in the process of supplying the internal pressure and inflating the green case, if the foot width is narrowed and the foot width becomes narrower than the foot width related to the ply thread length, the air seal for molding cannot be performed and the molding of the second molding machine becomes impossible. The tire size that can use the drum is limited.

To solve this problem, a method of providing a bead stopper on the outside of the raw case to enable air sealing even with a narrow foot width is often used, but the width of the bead portion of the tire is the size of the tire. Since it differs for each tire size, a tire support unit for the molding drum is required for each tire size, and size switching requires man-hours and time.

The present invention has been made in view of the above points,
The purpose thereof is to provide a tire raw case fixing method and device applicable to raw cases of various sizes, by preventing centering failure and deformation of the raw case feet when setting the raw case. .

[0008]

In order to achieve the above object, the present invention surrounds an inner support and an outer support which are provided at a plurality of annular positions around a main shaft of a molding drum and which are expandable and contractable independently of each other. A step of supporting the tire raw case so that the beat portion of the tire raw case is located at a position, a setting step of expanding the diameter of the inner support and abutting the inside of the bead portion to support the tire raw case, and the same setting At the same time as the step, a fixing step of expanding the diameter of the outer support and abutting the outer side of the bead portion to press and fix the bead portion to the inner support, and a lock for fixing and locking the diameters of the inner support and the outer support. The method of fixing the tire raw case comprises the steps of:

Since the raw case is supported by the expanded inner support and the bead portion of the raw case is pressed and fixed to the inner support by the expanded outer support, the foot width is not widened, and the centering failure or the raw case foot is prevented. It does not cause deformation. The bead portion of the raw case can be fixed from the outside, and it can be applied to raw cases of various sizes.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention shown in FIGS. 1 to 7 will be described below.

FIG. 1 shows a part of a fixing device for a raw case 1 on a second molding drum, in which a base body 12 is constructed around a main shaft 11 located on a central axis XX.
The base body 12 constitutes an air cylinder 13 in which annular pistons 15 and 16 are slidably fitted in an annular cavity 14 centered on the central axis XX in the central axis XX direction.

The piston 15 has a shape in which one end of a cylindrical portion 15a is extended in the radial direction to form a collar portion 15b, and the piston 15 is inserted into an annular cavity 14 of the air cylinder 13 and is inserted from the base body 12 The detent pin 19 protruding into the cavity 14 is fitted into a circular hole formed in the flange portion 15b of the piston 15 and
The rotation of 15 is prevented and only sliding in the direction of the central axis XX is allowed.

On the other hand, the piston 16 is a cylindrical portion 15 of the piston 15.
The inner cylindrical portion 16a slidably fitted to the outer periphery of a, the outer cylindrical portion 16b slidably fitted to the outer peripheral surface of the cavity 14 of the air cylinder 13, and the both cylindrical portions 16a, 16b are tapered. It is a cone type piston composed of a cone portion 16c connected in a circular shape, and the opposite side of the cone portion 16c is opened to form an annular groove space 16d therein.

As shown in FIG. 2, the cone portion 16c is provided with a plurality of cams 17 and 18 of two kinds, which are projected as a set. The outer peripheral surfaces of the cams 17, 18 are composed of tapered surfaces 17a, 18a and circumferential surfaces 17b, 18b.
The taper surface 17a of the other cam 17 has a large inclination angle a, and the circumferential surface 18b has a larger diameter than the other circumferential surface 17b and forms a step.

The piston 16 provided with such cams 17 and 18 is
The piston 15 fits in the cylindrical portion 15a of the piston 15 and moves together with the sliding of the piston 15 in the direction of the central axis, and also can slide independently of the piston 15 in the direction of the central axis.

A hollow disk-shaped slide rail retainer 21 provided so as to cover the front of the air cylinder 13 has bolts 22,
23 is threaded through from the outside, the tip of one bolt 22 abuts the end surface of the cylindrical portion 15a of the piston 15 to regulate the sliding of the piston 15, and the tip of the other bolt 23 is the cylindrical portion of the piston 16. It serves as a stopper that abuts against the end face of the piston 16a and restricts the sliding of the piston 16, and the stop position of the piston 15, 16 can be adjusted by changing the screwed state of the bolts 22, 23.

A key 20 for preventing the rotation of the piston 16 with respect to the piston 15 is provided on the cylindrical portion 15a of the piston 15 so as to extend in the central axis direction on the inner peripheral surface of the cylindrical portion 16a of the piston 16. The key 20 is slidably fitted in the formed groove.

A combination of the inner support 25 and the outer support 30 is fitted in the space between the slide rail retainer 21 for covering the front of the air cylinder 13 and the outer wall of the air cylinder 13 so as to be freely expandable and contractible in a radial direction. Have been combined.

The inner support 25 is U-shaped in a top view (see FIG. 3), and the outer support 30 is slidably fitted inside thereof. Inner support 25, outer support 30 outer peripheral end 25
a and 30a have an arc shape, the outer peripheral end 25a of one inner support 25 is formed to have a constant peripheral surface 25b, and a flange 25e is projectingly provided on the inner end thereof, and the other end 30 of the outer support 30 is formed.
The peripheral surface 30b of a is tapered inward.

Grooves 25c are circumferentially formed on both circumferential surfaces 25b and 30b.
30c is formed, and the spring 34 is fitted in the groove 25c, 30c so that the inner support 25 and the outer support 30 are always biased toward the center.

Roller followers 26 and 31 are rotatably attached to the inner end corners of the base ends 25d and 30d of the inner support 25 and the outer support 30, respectively. Is the cam 17 of the piston 16,
Facing 18

Therefore, when the piston 16 moves to the right side in FIG. 1, the tapered surfaces 17a and 18a of the cams 17 and 18 contact the roller followers 26 and 31, respectively, and the tapered surfaces 17a and 18a rotate while rotating the roller followers 26 and 31. The diameter of the inner support 25 and the outer support 30 can be increased at different speeds by moving up 18a.

One edge is fixed to the peripheral surface 25b of the inner support 25 and the corner of the flange 25e, and a rubber member 35 extends with slack so as to cover the inner side of the inner support 25, and the other edge is the air cylinder of the base body 12. It is fixed to the outer wall of 13. The inner support 25 and the outer support 30 have circumferential surfaces 25b and 30b covered with a band-shaped cover member 36.

On the other hand, the base body 12 has an air cylinder.
An air passage 40 for supplying air to the cavity 14 between the piston 13 and the piston 15 and an air passage 41 for supplying air to the groove space 16d of the piston 16 are formed. The air passage 41 communicates with the air passage 42 formed inside the piston 15,
Air is supplied between the piston 15 and the piston 16 via the air passage 42.

This tire raw case fixing device has the above-mentioned structure, and its operation will be described below with reference to FIGS.

First, as shown in FIG. 5, when the pistons 15 and 16 of the air cylinder 13 are contracted and the inner support 25 and the outer support 30 are contracted, the raw case 1 is set at a predetermined position. That is, the raw case 1 is supported so that the bead portion 2 of the raw case 1 is positioned so as to surround the inner support 25 and the outer support 30.

Next, as shown in FIG. 6, when air is supplied into the cavity 14 of the air cylinder 13 through the air passage 40, the piston 15 expands together with the piston 16 and the piston 16 expands.
The cams 17 and 18 formed on the cone portion 16c contact the roller followers 26 and 31, and expand the inner support 25 and the outer support 30 through the roller followers 26 and 31.

At this time, since the taper surface 18a of the cam 18 forms a steeper surface, the outer support 30 has a faster diameter expansion speed, and the cover member 36 along the peripheral surface 30b inclined first inward of the outer support 30 is formed. The bead portion 2 is pressed inward by abutting the bead portion 2 of the case 1, and the bead portion 2 is fixed at a predetermined position by pressing the bead portion 2 through the rubber member 35 against the flange 25e of the inner support 25 which has been expanded in diameter afterwards. To do.

Immediately before the roller followers 26, 31 are completely raised, the piston 15 comes into contact with the bolt 22 and stops, and the inner support 2
5. The work of fixing the bead portion 2 by the outer support 30 is completed.

Next, as shown in FIG. 7, when air is supplied to the groove space 16d of the piston 16 through the air passages 41 and 42, the piston 16 independently expands with respect to the stopped piston 15, and the roller follower 26, 31 is the tapered surface of cams 17 and 18
By moving from 17a, 18a to the flat circumferential surfaces 17b, 18b, the inner support 25 and the outer support 30 are in a locked state for stably maintaining the expanded diameter state.

In this locked state, the center ring when the raw case 1 is fixed is achieved, and the air seal due to the pressure contact between the rubber member 35 and the bead portion 2 is completed.

As described above, since the tire raw case fixing device of the present invention does not change the foot width of the bead portion 2 when fixing the raw case 1, the rubber member 35 for air seal is not deformed left and right unevenly. Does not cause ring failure.

Also, no deformation around the beads occurs. Even if the foot width is narrowed when the raw case expands, the outside support 30
However, since the beat portion 2 is pressed from the outside by the inclined peripheral surface 30b, no air seal defect occurs.

Even if the width of the bead portion 2 of the raw case 1 is different, if the bead portion 2 is located on the inclined surface of the peripheral surface 30b of the outer support 30, the bead portion 2 is pushed inward by the diameter expansion of the outer support 30. Since it can be air-sealed, the size range of the raw case that can be used with the same support is wide. Therefore, it is possible to significantly reduce the number of man-hours involved in size switching, and it is not necessary to have jigs and tools for each size, and cost reduction can be achieved.

As shown in FIG. 8, the peripheral surface of the outer support 30
By increasing the inclination angle of 30b, the range of applicable tire size is narrowed, but the sealing force of the bead portion 2 is increased, and it can be applied to tire molding with high internal pressure.

[0036]

According to the present invention, the bead portion is fixed to the inner support by the pressure applied from the outside by the outer support to support the raw case without expanding the foot width of the raw case. Can be completely secured. It can also be applied to raw cases with different tire sizes, and the size can be easily switched, saving time and labor.

[Brief description of drawings]

FIG. 1 is a partial cross-sectional view of a tire raw case fixing device according to an embodiment of the present invention.

FIG. 2 is a partially omitted perspective view of the same device.

FIG. 3 is a top view of a support section of the same device.

FIG. 4 is a front view of the support unit.

FIG. 5 is a partial cross-sectional view showing a state before fixing the raw case of the device.

FIG. 6 is a partial cross-sectional view of the device when the raw case is fixed.

FIG. 7 is a partial cross-sectional view of the device when the raw case is locked.

FIG. 8 is a diagram showing a shape of an outer support according to another embodiment.

[Explanation of symbols]

1 ... Raw case, 2 ... Bead part, 11 ... Main shaft, 12 ... Base body, 13 ... Air cylinder, 14 ... Cavity, 15, 16 ... Piston, 17, 18 ... Cam, 19 ... Pin, 20 ... Key, 21 ... Slide rail retainer, 22, 23 ... Bolt, 25 ... Inner support, 26 ... Roller follower, 30 ... Outer support, 31 ... Roller follower, 34 ... Spring, 35 ... Rubber member, 36 ... Cover member, 40, 41, 42 ... Air passage.

Claims (2)

[Claims] 1. A tire raw case is provided so that a beat part of the tire raw case is located at a position surrounding a plurality of inner supports and outer supports which are provided at annular positions around a main shaft of a molding drum and independently expand and contract. A step of supporting, and a setting step of expanding the diameter of the inner support to abut against the inner side of the bead portion to support the tire raw case, and at the same time as the setting step, expanding the diameter of the outer support to outside the bead portion A method for fixing a raw tire case, comprising: a fixing step of abutting against the inner support and pressing and fixing the bead portion to the inner support; and a locking step of fixing and locking the diameters of the inner support and the outer support. 2. An inner support, which is provided at a plurality of annular positions around the main shaft of the molding drum and is supported so as to be expandable and contractible, and an outer support which is provided so as to correspond to the outer sides of the plurality of inner supports and is supported so as to be expandable and contractible. A tire comprising: a support; and an expansion / contraction cylinder having a cone-type piston having a double taper structure for expanding / contracting the inner support and the outer support independently of each other and a columnar structure for fixing the inner support and the outer support at a constant diameter. Fixing device for raw case.