JP2002079589A - Method of correcting and keeping shape of unvulcanized tire and device therefor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of correcting and keeping the shape of an unvulcanized tire and a device therefor which enable remarkable improvement of the performance of a tire after vulcanization molding by holding parallel the inside diameter parts of upper and lower beads of the unvulcanized tire on standby for vulcanization and by correcting them to be in the state of a perfect circle for a prescribed time. SOLUTION: In the device for correcting and keeping the shape of the unvulcanized tire, a pair of upper and lower divided circular-arc or fan-shaped correcting plates 10 in a plurality which are made to operate to expand and contract horizontally by an extending-contracting operation of an extensible-contractible rod 8 of an elevating cylinder 7 by the medium of an expansion-contraction mechanism 9 are provided at the fore end part of the rod 8. In the expansion-contraction mechanism 9, a cylindrical guide member 12 which is made to move up and down along the axial direction of the elevating cylinder 7 by the extending- contracting operation of the rod 8 and can be positioned is fitted on the outer peripheral part of the fore end of the cylinder 7 having a stopper 11 provided at the fore end. Fixed plates 13a and 13b and a stopper plate 14 are provided respectively at the fore end part of the guide member 12, in the vicinity of the center in the longitudinal direction thereof and in the base end part thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for correcting and holding an unvulcanized tire, and more particularly to a molded unvulcanized tire (green tire).
To correct the shape of unvulcanized tires to improve the performance of tires after vulcanization and molding, and to improve the performance of the tires after vulcanization.

[0002]

2. Description of the Related Art In a general tire molding process, from a tire assembly (molding) process to a vulcanization process,
Through the process of moving and storing an unvulcanized tire, the tire may be crushed or deformed into an elliptical shape due to the viscoelastic properties of the tire material. It has been found that it has at least a negative effect on the uniformity (uniformity) and weight balance of the product tires later.

[0003]

For this reason, conventionally, the inner diameter of the upper bead portion of a molded unvulcanized tire is suspended by holding a plurality of claws to suspend the preceding unvulcanized tire. A method of centering a deformed unvulcanized tire or correcting it into a perfect circle by waiting is performed.

However, such a conventional method is not a method of holding only one side of an unvulcanized tire or straightening while holding the upper and lower bead portions in parallel. It could not be corrected or retained in a circle.

[0005] It is an object of the present invention to maintain the upper and lower bead inner diameters of an unvulcanized tire in a vulcanization standby state in parallel to correct it into a perfect circle, and to maintain the same for a certain period of time. It is an object of the present invention to provide a method for correcting and maintaining the shape of an unvulcanized tire and a device therefor which can significantly improve the performance.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a method for correcting the shape of an unvulcanized tire and a method for holding the unvulcanized tire, the method comprising: Inserting a shape correcting and holding device, and expanding a pair of upper and lower arc-shaped correcting plates divided into a plurality in the circumferential direction of the shape correcting and holding device on the inner diameter portion of the upper and lower beads of the unvulcanized tire. The gist of the present invention is to hold the deformed bead portion so as to correct it to a perfect circular state.

Further, in the device for correcting the shape of an unvulcanized tire according to the present invention, the distal end of an extensible rod of an elevating cylinder is horizontally extended / retracted by an extending / retracting operation of the rod by the extension / retraction operation of the rod. The gist is to provide a pair of upper and lower divided correction plates.

The expansion and contraction mechanism includes a guide member which can be moved up and down along the axial direction of the cylinder by the expansion and contraction operation of a rod, and which is positioned on the outer periphery of the tip of the lift cylinder. A fixed plate is provided in the vicinity of the center of the direction, and a guide rod that can be extended and contracted in a direction perpendicular to the axial direction of the cylinder is provided therebetween, and in the vicinity of the fixed plate, the guide member and the rod are provided via an elastic member. A support plate and a slide plate that move along are provided, and the upper and lower slide plates are connected by a lifting link arm with a guide rod as a fulcrum, and a pair of upper and lower support plates and a slide plate are connected by an expansion / contraction arm, respectively. A vertically extending / retractable arm and a tip of a guide rod are connected to a system arranged in parallel with the rod. Coupled to shift, and constitutes provided detachably this plural arc-shaped correction plate which is divided into a plurality of circumferentially shaft.

A plurality of the arc-shaped correction plates are provided at a predetermined interval on the outer peripheral portion of the lifting cylinder, and the arc-shaped correction plate is formed corresponding to the bead inner diameter of the unvulcanized tire. is there.

[0010] The present invention is configured as described above, and is capable of lifting and lowering the shape of the uncured tire while waiting for vulcanization.
Inserting the holding device, the inner portion of the upper and lower beads of the unvulcanized tire, expanded and pressed a pair of upper and lower arc-shaped correction plate divided into a plurality in the circumferential direction of the shape correction and holding device, By maintaining the deformed bead portion so as to correct it into a perfect circle, the tire performance after vulcanization molding can be remarkably improved.

[0011]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic configuration diagram of an apparatus for correcting and holding an unvulcanized tire for carrying out the method for correcting and holding an unvulcanized tire according to the present invention, and FIG.
FIG. 2B is an enlarged front view of the holding device, and FIG.
FIG. 1 shows a plan view taken in the direction of an arrow, where 1 is a tire holding stand, and 2 is a plurality (three in this embodiment, but not particularly limited) of horizontally holding a molded unvulcanized tire W (green tire). The holding arm 3 is a support rod that is erected at the center of the plurality of holding arms 2, and a tip of the support rod 3 is provided with a shape correction / holding device 4 according to the embodiment of the present invention.
Is installed.

Reference numeral 5 denotes a vertical loader which holds a bead inner diameter portion Wa of the unvulcanized tire W and transports it to the position of the upper and lower molds 6 of a vulcanizing device (not shown).

The uncured tire shape correcting / holding device expands / contracts in the horizontal direction via an expansion / contraction mechanism 9 at the end of an extensible rod 8 of an elevating cylinder 7 by the expansion / contraction operation of the rod 8. A pair of upper and lower divided plural sheets (four sheets in this embodiment, but more is preferable)
An arc-shaped or fan-shaped correction plate 10 is provided.

Further, it is preferable that the correction plate 10 be set so that the radial dimension is set between the inch diameter of the unvulcanized tire W or the inch diameter + 5 mm, and set and pressed so as to be a perfect circle on the circumference. . Further, in the embodiment of the present invention, since the upper and lower bead portions Wa of the unvulcanized tire W are pressed and set by the plurality of correction plates 10, each bead portion Wa is held in a perfect circle, and at the same time, the upper and lower beads are removed. It will be set accurately without any center misalignment.

The expansion / contraction mechanism 9 has a stopper 11 at its tip.
Is moved up and down along the axial direction of the cylinder 7 by the expansion and contraction operation of the rod 8,
A cylindrical guide member 12 which can be positioned and is fitted is fitted. Fixing plates 13a, 13b are provided at the distal end, near the center in the longitudinal direction, and at the proximal end of the guide member 12.
A stopper plate 14 is provided.

Further, at several places in the circumferential direction of the guide member 12 between the fixing plates 13a and 13b (in this embodiment, 9 places).
There are four places at 0 ° intervals, but the number is not particularly limited.)
Is provided with a guide rod 15 that can extend and contract in a direction perpendicular to the axial direction of the cylinder 7. The fixed plate 1
Elastic members 16 such as springs are provided near 3a and 13b.
a, 16b, and 16c, support plates 17a and 17b that move along the guide member 12 and the rod, and slide plates 18a and 18b, and the upper and lower slide plates 18a and 18b are provided with guide rods. It is connected by a lifting link arm 19 that expands and contracts in the vertical direction with the fulcrum 15 as a fulcrum O.

A pair of upper and lower support plates 17a, 17
b and the slide plates 18a, 18b
0a, 20b, and the upper and lower arms 20a, 20b and the tip of the guide rod 15 are connected to a plurality of shafts 21 arranged in parallel with the rod 8.

An arc-shaped correction plate 10 divided into a plurality in the circumferential direction is detachably attached to the plurality of shafts 21. The correction plate 10 has a curvature of the bead inner diameter Wa of the unvulcanized tire W. Are provided at predetermined intervals on the outer peripheral portion of the lifting cylinder 7.

In this embodiment, the correction plate 10
Are provided at four positions at 90 ° intervals on the outer peripheral portion of the elevating cylinder 7, but the number is not limited.

It is preferable that the width between the upper and lower portions of the straightening plate 10 is set to 60% to 80% of the drum width in the molding step, or between +10 mm of the value.

Next, a method of correcting the shape of the unvulcanized tire W and holding the same will be described with reference to FIGS. 1 and 3 (a) and 3 (b).
This will be described with reference to the process diagram of (4).

First, as shown in FIG. 3 (1), the shape correcting / holding device 4 at the standby position is horizontally held on the holding arm 2 of the tire holding base 1 as shown in FIG. 3 (2). The shape correcting / holding device 4 is inserted downward into the center of the unvulcanized tire W waiting for vulcanization via the elevating cylinder 7, and is positioned at a predetermined position via the stopper 11 and the stopper plate 14.

That is, when the rod 8 is extended by extending the elevating cylinder 7, the cylindrical guide member 12 is also lowered, and the stopper plate 14 is brought into contact with the stopper 11 provided at the tip of the elevating cylinder 7. It is positioned in contact. At this time, the shape correcting / holding device 4 is pressed by only the vertical movement due to the reaction force of the elastic member 16c.

After the shape correcting / holding device 4 is positioned inside the center of the unvulcanized tire W in this manner, FIG.
As shown in (3), the lifting cylinder 7 is connected to the elastic member 16.
When the extension operation is further performed against the elastic force of c, the slide plate 18b fixed to the rod 8 moves downward.

At the same time, the elevating link arm 19 attached to the slide plate 18b extends in the longitudinal direction about the fulcrum O of the guide rod 15, and the slide plate 18 fixed to the other end of the elevating link arm 19 is extended.
a, and the support plates 17a, 1
The vertical expansion / contraction arms 20a, 20b connected to the slide plate 18a and the slide plates 18a, 18b extend in the tire radial direction to move the shaft 21 in the radial direction, and the arc-shaped (or fan-shaped) correction plate attached to the shaft 21. By 10, several places on the inner walls of the upper and lower beads of the unvulcanized tire W are simultaneously pressed in the radial direction to correct the deformed upper and lower bead portions Wa into a perfect circle.

In this embodiment, the correction plate 10
Are arranged at four places in the circumferential direction of the lifting cylinder 7, so that the roundness correction of the unvulcanized tire W is performed simultaneously at four places in the circumferential direction. When the inner walls of the upper and lower beads are corrected at the same time, the elastic members 16a, 16
The movement in the height direction is suppressed by the elastic reaction force b.

As shown in FIG. 3D, the support plate 17b is pressed downward by the slide plate 18b, and the support plate 17b is pressed downward by the vertical movement of the pair of upper and lower correction plates 10 in the vertical direction. 18
The support plate 17a is pressed upward by a to compress the elastic members 16a and 16b, and the pair of upper and lower correction plates 10 are slid by the shaft 21 to abut the bead inner diameter portion of the unvulcanized tire W and are deformed. This is to correct the inner diameter of the bead.

As described above, the correction holding time of the deformed bead inner diameter portion is preferably set to at least 5 minutes or more.

When the unvulcanized tire is vulcanized by correcting the deformation of the unvulcanized tire by the above method, the value of the tire uniformity (uniformity: UF) of the vulcanized product tire is as follows. Was. * Tire uniformity (UF) measurement conditions: Conforms to JASO C607

[Table 1] * Index display: The smaller the index, the better. RFV: Radial Force Variation: Fluctuation of radial reaction force LFV: Lateral Force Variation: Fluctuation of front-rear reaction force RRO: Radial Run out: Maximum value of radial runout

[0031]

According to the present invention, since the upper and lower bead inner diameters of the unvulcanized tire waiting for vulcanization are kept parallel to each other, the tire is corrected to a perfect circular state, and is maintained for a certain period of time. Thus, there is an effect that tire performance after vulcanization molding can be remarkably improved.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an apparatus for correcting and holding an unvulcanized tire for carrying out a method for correcting and holding an unvulcanized tire according to the present invention.

FIG. 2 (a) is an enlarged front view of a shape correction / holding device,
FIG. 2B is a plan view taken along the line AA in FIG.

FIGS. 3 (a) and (b) of (1) to (4) are a front view and a plan view in a process chart of a method of correcting and holding an unvulcanized tire.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Tire holding stand 2 Holding arm 3 Support rod 4 Shape correction / holding device 5 Vertical loader 6 Vertical mold 7 Elevating cylinder 8 Rod 9 Enlargement / reduction mechanism 10 Straightening plate 11 Stopper 12 Guide member 13a, 13b Fixing plate 14 Stopper plate 15 Guide rod 16a , 16b, 16c Elastic member 17a, 17b Support plate 18a, 18b Slide plate 19 Elevating link arm 20a, 20b Vertically expanding / contracting arm 21 Shaft W Unvulcanized tire Wa Bead inner diameter

Claims (6)

[Claims] An unvulcanized tire which is waiting for vulcanization is positioned by inserting a vertically movable shape correcting / holding device into an inner portion of an upper and lower bead of the unvulcanized tire. A shape of an unvulcanized tire that expands and presses a pair of upper and lower arc-shaped correction plates that are divided into a plurality in the circumferential direction of the holding device, and corrects and holds the deformed upper and lower bead portions in a perfect circular state and holds them. Straightening and holding method. 2. The method for correcting and holding an unvulcanized tire according to claim 1, wherein the time for pressing and holding the inner diameter portions of the upper and lower beads by expanding the straightening plate is set to at least 5 minutes or more. 3. An uncured vulcanizer comprising a pair of upper and lower divided straightening plates which are horizontally extended and contracted by a telescopic operation of the rod by a telescopic operation of the extensible rod of the elevating cylinder. Tire shape correction and holding device. 4. The expansion / contraction mechanism covers a guide member which can be moved up and down along the axial direction of the cylinder by the expansion and contraction operation of a rod on the outer periphery of the tip of the lift cylinder, and which can be positioned. A fixed plate is provided in the vicinity of the center in the longitudinal direction, and a guide rod that can be extended and contracted in a direction orthogonal to the axial direction of the cylinder is provided therebetween, and the guide member and the elastic member are provided in the vicinity of the fixed plate. A support plate and a slide plate that move along the rod are provided, and the upper and lower slide plates are connected by a lifting link arm with a guide rod as a fulcrum, and a pair of upper and lower support plates and a slide plate are connected by an expansion / contraction arm, respectively. The vertical expansion / contraction arm and the end of the guide rod are connected to a system arranged in parallel with the rod. 4. The device for correcting and shaping the shape of an unvulcanized tire according to claim 3, wherein an arc-shaped correction plate divided into a plurality of pieces in the circumferential direction is detachably connected to the plurality of shafts. 5. The uncured tire shape correction and holding device according to claim 3, wherein a plurality of the arc-shaped correction plates are provided at predetermined intervals on an outer peripheral portion of the lifting cylinder. 6. The device for correcting and holding a shape of an unvulcanized tire according to claim 3, wherein the arc-shaped correction plate is formed corresponding to an inner diameter of a bead of the unvulcanized tire.