JP2013136204A - Method for producing flap, and apparatus for producing unvulcanized flap - Google Patents

Abstract

PROBLEM TO BE SOLVED: To produce a flap economically and efficiently without carrying out additional processing while preventing conventional generation of scrap.SOLUTION: A method for producing a flap includes: a process in which, by a molding drum 20 composed of a center drum and side drums arranged on both sides of the center drum, unvulcanized ribbon rubber wound/laminated on the molding drum 20 is molded into an unvulcanized flap 34 having a center part having a prescribed thickness and taper parts which adjoin the center part and have a diameter that is larger than that of the center part and in which the end parts become tips, respectively; a process in which a reinforcing member 40 is attached at a valve installing position of the molded unvulcanized flap; and a process in which the unvulcanized flap 34 attached with the reinforcing member 40 is vulcanized.

Description

  The present invention relates to a method for manufacturing a tube-filled tire flap and an apparatus for manufacturing an unvulcanized flap.

  In a tire with a tube, if the tip (bead toe) of the bead part is lifted from the rim (rim wheel) during traveling and a gap is formed between the bead toe and the rim, the tube may enter the gap. If the tube is pinched between the bead toe and the rim, the tube will be damaged and in the worst case punctured.

  Therefore, conventionally, a rubber flap 30 is provided on the outer peripheral surface side of the rim 53 and between the bead portion 52 and the tube 50 as shown in the sectional view of the tube-filled tire of FIG. Suppression of damage has been done.

  The flaps are produced by a press vulcanization method in which a mold is filled with unvulcanized rubber and vulcanized, and an unvulcanized rubber is wrapped around a cylindrical molding ring (drum) in an oven. An open vulcanization method in which vulcanization is performed is known. In addition to this, a manufacturing method called an injection method using an injection mold is also known. Although this method can manufacture the flap with high accuracy, it is not widely used because the equipment is expensive.

  In the press vulcanization method, a dough (rubber dough) is extruded by a normal extrusion line, and this is cut into fixed lengths to obtain a dough 100 as shown in FIG. 12A. Subsequently, the dough 100 is put between a lower mold 110b and an intermediate mold 110c of a press type vulcanizer (vulcanizing press machine) (FIG. 10), and the upper mold 110a is lowered to crush and fluidize the dough 100. And is vulcanized to form a flap 120 having a shape shown in FIG.

13A and 13B are diagrams illustrating a method of manufacturing a flap. FIG. 13A shows a fabric 100a having a horizontally long rectangular cross section, and FIG. 13B shows a fabric 100b having a square cross section having the same cross-sectional area as that shown in FIG. 13A. FIGS. 13C and 13D show flaps 120a and 120b manufactured from the fabric of FIG. 12A. FIG. 13E is a cross-sectional view of the vulcanization mold 110 charged with the dough 100.
That is, when the flap 120 is manufactured based on the fabrics 100a and 100b having different heights h1 and h2, as shown in FIGS. 13C and 13D, the flaps 120a and 120b having the sizes H1 and H2 are large and small, respectively. Is obtained. At the time of this molding, as shown in FIG. 13E, the cloth 100 is pressed between the upper mold 110a and the lower mold 110b and flows into the gap between the upper mold 110a and the middle mold 110c arranged in the upper mold 110b. The difference in shape, that is, the difference between the horizontally long rectangle and the square does not affect the product dimensions of the flaps 120a and 120b to be molded.

  By the way, a valve 55 (FIG. 11) is attached to the tube 50 of the tube-equipped tire. Rubber forming the tube 50 and the like is softened by radiant heat from the brake drum, and the softened rubber is valved by the high internal pressure of the tube 50. It may bulge out from the hole 54 and blow out and puncture. Therefore, in order to reinforce the valve hole 54, the portion of the valve hole 54 of the flap 30 is made up of a dough 100 to compensate for the rubber volume, as shown in FIG. 12B.

  Further, in a conventional flap manufacturing method using a vulcanizing press, rubber is charged into the vulcanizing press for the purpose of protruding the dough during molding and vulcanization. Therefore, about 5 to 10% of the protruding rubber is generated with respect to the product weight, and this protruding rubber is removed by trimming after vulcanization and processed as scrap.

In the flap manufacturing method using the conventional vulcanizing press machine, there is a problem that the cost of damage due to the protruding rubber increases, but there are the following problems in addition to this problem. That is,
(1) Variations in the workmanship of products due to variations in work.
There is know-how in putting dough, and there is variation in the input position because it is done manually.
In other words, the dough 100 is actually put in while the vulcanizing pot is closed, but since the rubber flows in the vulcanization mold at that time, the flow of the rubber changes by changing the dosing position of the dough. (Mold) Rubber may not flow to the tip of 110. In that case, the sharp edge of the flap (gauge at the tip) does not meet the specifications (0.5 mm or less), and those that cannot be reworked become scrap.

(2) There is a problem on equipment (existing extrusion train).
That is, the conventional flap manufacturing method does not use a device dedicated to the flap, but also uses existing equipment, for example, a device for forming a top tread, and thus has the following problems.
(I) There are differences between units of rubber extruder and fixed length cutter accuracy at each factory.
(Ii) When compared with the top tread, the shrinkage amount increases because the thickness of the fabric gauge of the flap is large. Further, depending on the length of the cooling conveyor belt for the top tread, the flap may not be completely cooled.
(Iii) There are restrictions due to the opening size of the rubber extruder.
That is, when compared with the top tread, since there is a fabric thickness of the flap, there is a restriction on the shape of the fabric by the rubber extruder for the top tread.
(Iv) The width of the flap fabric is restricted by the train conveyor belt specifications.
That is, if an existing extrusion train is used, a flap may be caught in a gap between a conveyor belt and a weighing machine.

(3) There are other problems as described below.
(I) The length of the dough is set based on the inner diameter of the mold so that the dough is uniformly arranged on the mold periphery. The cross-sectional area of the fabric is adjusted for each set length. Adjustment of the extrusion process and jigs are necessary to adjust the cross-sectional area.
(Ii) Since the fabric is thick and cannot be stored as a scroll, it is cut into a fixed length and stored, but a fixed length cutting facility is required for that purpose, and a booking cart for storage is required.

(Iii) When the dough weight deviates greatly from the target value or the center value (process value), a large amount of TMA (recycled rubber) is generated. In other words, the weight of the dough is measured per unit length (1 m) using a continuous scale in the extrusion train, but when the weight per unit length exceeds the process value, The dough weight is out (failed), and a large amount of TMA is generated for process adjustment.
(Iv) Since the cloth used in the conventional flap manufacturing method is thick, a long water tank is required to cool the inside.
(V) A truck and pallet for each size is required to store the fabric, and in order to prevent adhesion during storage, surface treatment with a release material or coating with a poly sheet (synthetic resin sheet) etc. Management is necessary.

  On the other hand, as an open vulcanization method, a high-viscosity unvulcanized rubber is extruded as a belt-like material from a die that matches the cross-sectional shape of the flap, and the belt-like material is wound around the ring for ring formation. A method for manufacturing a tire flap is known in which a material is vulcanized together with the molding ring in an oven (see Patent Document 1).

  However, when manufacturing flaps by the open vulcanization method, high-viscosity unvulcanized rubber is extruded as a strip from a die that matches the cross-sectional shape of the flap. In the following, it is considered difficult to form a thin wall.

If the both ends in the width direction of the annular flap are not thinly formed to a certain thickness or less, a gap will be created between both ends of the flap and the inner surface of the tube. When the inner surface of the tube is repeatedly rubbed, there is a problem that stress concentrates on this portion and the tube may be broken in the vicinity of the upper end portion of the flap.
Therefore, in the conventional flap manufacturing method described in Patent Document 1, before or after vulcanization, a processing step for adding both ends in the width direction of the annular flap to a thickness of less than 0.5 mm is added. We are trying to solve the problem.

  The flap manufacturing method described in Patent Document 1 does not require a deburring step when manufacturing the flap with the conventional vulcanizing press, but before or after the vulcanization, the width direction of the flap. Since the process of processing both ends of this is added, there is still room for improvement in this respect.

JP 2006-218664 A

  The present invention has been made in view of the above problems in the conventional flap manufacturing method, and its purpose is to use a low-cost dedicated manufacturing apparatus without using existing equipment as in the prior art. Thus, it is possible to solve the above-mentioned conventional problems and eliminate the need for additional processing and scrap generation for deburring and flaps, and to manufacture the flaps economically and efficiently.

The present invention provides an unvulcanized ribbon rubber wound around a molding drum by a molding drum including a central drum and side drums arranged on both sides of the central drum, a central portion having a predetermined thickness, and the central drum. A step of forming an unvulcanized flap including a taper portion having a diameter larger than that of the central portion, and a reinforcing member at a valve mounting position of the formed unvulcanized flap. And a step of vulcanizing the unvulcanized flap provided with the reinforcing member.
The present invention is an apparatus for producing an unvulcanized flap, comprising: an unvulcanized ribbon rubber extruder; and a flap forming drum for laminating and winding ribbon rubber extruded from the unvulcanized ribbon rubber extruder, The forming drum includes a center drum and side drums arranged on both sides of the center drum, and the side drum is an unvulcanized flap manufacturing apparatus formed to have a larger diameter than the center drum. is there.

  According to the present invention, it is possible to eliminate the conventional deburring and additional processing steps of the flap, and thus to eliminate the generation of scrap, and to manufacture the flap economically and efficiently.

It is a figure which shows typically the procedure of the manufacturing method of the flap which concerns on embodiment of this invention. FIG. 2A is a diagram schematically showing a molding drum according to the first embodiment, and FIG. 2A shows a state in which ribbon rubber is laminated on the molding drum and both end portions in the width direction are formed into a flap material having a predetermined thickness. FIG. 2B is a view showing a state in which a flap material is formed to form an unvulcanized flap. It is a flowchart which shows the procedure of the manufacturing method of the flap which concerns on 1st Embodiment. FIG. 4A is an unvulcanized flap before molding, and FIG. 4B is a cross-sectional view of the unvulcanized flap after molding. FIG. 5A is a diagram schematically showing a molding drum according to the second embodiment, and FIG. 5A shows a state in which ribbon rubber is laminated on the molding drum and both end portions in the width direction are formed into a flap material having a predetermined thickness. FIG. 5B is a view showing a state in which a flap material is formed to become an unvulcanized flap. It is a flowchart which shows the procedure of the manufacturing method of the flap which concerns on 2nd Embodiment. It is a figure which shows typically the shaping | molding drum which concerns on 3rd Embodiment. It is a flowchart which shows the procedure of the manufacturing method of the flap which concerns on 3rd Embodiment. It is a figure which shows roughly each process of winding the dough extruded from the rubber extruder around a rotary body, and charging the wound dough in a vulcanization mold. It is sectional drawing in the state which prepared the dough in the vulcanization type | mold. It is sectional drawing of the tire which shows the position of the flap in a tire with a tube. It is a figure which shows the manufacturing method of the conventional flap. FIG. 13A is a diagram showing a flap manufacturing method, FIG. 13A shows a fabric having a horizontally long rectangular cross section, FIG. 13B shows a fabric having a square cross section having the same cross-sectional area as that shown in FIG. 13A, and FIGS. FIG. 13 shows a flap manufactured from the fabric of FIGS. FIG. 13E is a cross-sectional view of a vulcanization mold charged with dough.

Embodiments of the present invention will be described below with reference to the drawings. First, the principle of the present invention will be described.
Drawing 1 is a figure showing typically the procedure of the manufacturing method of the flap concerning the embodiment of the present invention.
When the flap according to the present invention is manufactured, as shown in FIG. 1, ribbon rubber 12 extruded in a ribbon shape from a die using a conventional rubber extruder 10 is spirally wound and laminated on a forming drum 20. Thus, an unvulcanized flap 34 is formed. Subsequently, in order to reinforce the valve mounting position 34a of the formed unvulcanized flap 34, a separately created reinforcing rubber member 40 was attached by pasting or the like, and a reinforcing rubber member 40 as a reinforcing member was attached. The unvulcanized flap 34 is accommodated in a split mold of a vulcanizer (not shown) and vulcanized to form the flap 30.
In addition, the split mold to be used is known per se, and a mold body composed of a multi-part mold and upper and lower side molds, and an outer periphery of the multi-part mold for moving these in the radial direction with respect to the mold center. It consists of a segment and container ring and a top plate.

  FIG. 2 is a diagram schematically showing the molding drum according to the first embodiment. FIG. 2A is a diagram in which the ribbon rubber 12 is laminated on the molding drum 20 and the flap material 32 having a predetermined thickness at both ends in the width direction. FIG. 2B is a diagram showing a state in which the flap material 32 is formed and an unvulcanized flap 34 is formed.

The forming drum 20 has a cylindrical shape as a whole, and includes a central drum 22 and left and right side drums 24 disposed adjacent to the central drum 22 along a rotation axis (not shown), and is not shown. It is supported by a drive mechanism so as to be rotatable on a common rotating shaft.
In this embodiment, the central drum 22 is configured to be expandable / contractable by a plurality of links (not shown), and the surfaces of the unvulcanized flaps 34, the left and right side drums 24, and the central drum 22 can be expanded and contracted, for example, rubber. Is formed as a single forming drum 20 as a whole.

  Further, at least one of the left and right side drums 24 is configured to be able to expand and contract to the diameter of the central drum 22 whose diameter has been reduced so that the unvulcanized flap 34 after forming can be removed from the forming drum 20. .

  Here, any mechanism can be used as the expansion / contraction mechanism of the forming drum 20. For example, an expansion / contraction drum having a plurality of divided segments and having a mechanism for expanding / contracting each segment in the radial direction, a spring that constantly urges the drum in the diameter expansion direction or the diameter reduction direction, and Known or well-known configuration including a fluid pressure drive means that drives in the direction of contraction against the spring when the diameter is expanded, a fluid cylinder connected to a fluid supply source, or a configuration that widens a link mechanism connected to a rotary drive device The mechanism can be used.

  In the present embodiment, as the expansion / contraction mechanism of the central drum 22, the central drum 22 uses, for example, a hydraulic mechanism that operates the link mechanism to widen the drum, and the left and right side drums 24 are radially outward with the rotation axis as the center. The expansion / contraction means 24a (FIG. 5) provided with a finger-shaped link that opens to the center is provided, and the expansion / contraction can be performed by moving the central portion of the finger-shaped link along the rotation axis of the drum with a drive mechanism.

Next, the procedure of the method for manufacturing the flap 30 will be described with reference to the flowchart shown in FIG.
First, as shown in FIG. 2A, the central drum 22 is expanded to the same diameter as the left and right side drums 24, and the forming drum 20 (drums 22 and 24) is rotated by a rotation mechanism (not shown) in this state (S101). Next, the ribbon rubber 12 extruded from the die of the rubber extruder 10 (FIG. 1) is spirally wound around the rotating molding drum 20 and laminated, and the laminated cross section has a predetermined thickness as shown in FIG. 4A. The flap material 32 is formed such that the substantially flat central portion 32a, the tapered portion 32b following the central portion 32a, and the tip of the tapered portion 32b become a sharp tip portion 32c of 0.5 m or less (S102). ).

  Subsequently, as shown in FIG. 2B, the diameter of the central drum 22 is reduced by the expansion / contraction mechanism in a state where the pressing roller 25 is pressed against the position corresponding to the central drum 22 of the flap material 32 (S103). As a result, the central portion 32a of the flap material 32 is reduced in diameter, and as a result, the tapered portion 32b is bent inward at the side drum 24, and an unvulcanized flap having the cross-sectional shape shown in FIG. The vulcanization flap 34 is formed (S104).

When the unvulcanized flap 34 is formed in this way, the reinforcing rubber member 40 is attached to the valve mounting position 34a of the unvulcanized flap 34 by sticking or the like (S105; see FIG. 1). Subsequently, the unvulcanized flap 34 formed by reducing the diameter of one side drum 24 is removed from the forming drum 20 (S106).
Subsequently, the unvulcanized flap 34 is put into a split mold and vulcanized (S107), and the product flap 30 is formed.

Next, a method for manufacturing the flap 30 according to the second embodiment will be described.
FIG. 5 is a diagram schematically showing a molding drum according to the second embodiment. FIG. 5A is a diagram in which ribbon rubber 12 is laminated on the molding drum 20 and a flap material 32 having a predetermined thickness at both ends in the width direction. FIG. 5B is a diagram showing a state where the flap material 32 is formed into an unvulcanized flap.
The molding drum 20 is formed in a cylindrical shape as in the first embodiment, and includes a central drum 22 and left and right side drums 24 disposed adjacent to the central drum 22 along its rotation axis (not shown). It is rotatably supported on a common rotating shaft by a driving mechanism (not shown).

In the present embodiment, the central drum 22 is not expanded or contracted, while the side drum 24 is configured to be expanded or contracted by expansion / contraction means 24a having finger-like links. The surfaces of the left and right side drums 24 and the central drum 22 are covered with a stretchable material, for example, a rubber cover member 26, and are configured as one molding drum 20 as a whole.
Further, when the unvulcanized flap 34 after molding is removed from the molding drum 20, one of the left and right side drums 24 is reduced to the diameter of the central drum 22.

FIG. 6 is a flowchart showing the procedure of the flap manufacturing method according to the second embodiment.
When manufacturing a flap, first, the left and right side drums 24 are set to a reduced diameter position in accordance with the diameter of the central drum 22, the molding drum 20 (the central drum 22, the side drum 24) is rotated (S201), and rubber extrusion is performed. The ribbon rubber 12 pushed out from the die of the machine 10 (FIG. 1) is laminated while being wound around a rotating forming drum 20 by a driving mechanism (not shown), and is substantially flat with a predetermined thickness (gauge) as shown in FIG. 4A. The flap material 32 is formed so that the central portion 32a, the tapered portion 32b following the central portion 32a, and the tip of the tapered portion 32b become a sharp tip portion 32c of less than 0.5 m (S202). Subsequently, the side drum 24 is expanded in diameter by the expansion / contraction means 24a having the finger-shaped link while pressing the pressing roller 25 at a position corresponding to the central drum 22 of the flap material 32 (S203). As a result, the taper portion 32b of the flap material 32 is bent so as to open outward to form the unvulcanized flap 34 having the cross-sectional shape shown in FIG. 4B (S204).

Thereafter, the reinforcing rubber member 40 is attached to the valve mounting position of the unvulcanized flap 34 by sticking or the like (S205). Next, the diameter of one side drum 24 is reduced to the same diameter as that of the central drum 22, and the formed unvulcanized flap 34 is removed from the forming drum 20 (S206).
Next, the unvulcanized flap 34 is put into a split mold and vulcanized (S207), and the product flap 30 is formed.

In any of the above embodiments, the flap material 32 is once formed on the molding drum 20 and then the unvulcanized flap 34 is molded. However, the unvulcanized flap 34 does not follow the above procedure, and the ribbon rubber 12 is formed on the molding drum 20. The unvulcanized flap 34 can also be manufactured by winding and laminating.
Hereinafter, the manufacturing method of the flap will be described as a third embodiment.
FIG. 7 is a diagram schematically showing a forming drum according to the third embodiment.
The molding drum 20 is generally cylindrical with a central portion constricted, and has a small-diameter central drum 22 and a large-diameter left and right side drum disposed adjacent to the central drum 22 along its rotation axis (not shown). 24, and is rotatably supported on a common rotating shaft by a driving mechanism (not shown).

  In the present embodiment, the central drum 22 does not expand and contract, and the side drum 24 may be originally fixed. However, in order to remove the formed unvulcanized flap 34, at least one side drum 24 is configured to be expandable and contractable. ing. The expansion / contraction mechanism is the same as in the first and second embodiments. Further, the surfaces of the left and right side drums 24 and the central drum 22 are covered with a stretchable material, for example, a rubber cover member 26 so as to be configured as one molding drum 20 as a whole.

FIG. 8 is a flowchart showing the procedure of the flap manufacturing method according to the third embodiment.
When manufacturing a flap, first, the side drums 24 on both sides of the central drum 22 are set in a state in which the diameter is increased. In this case, one of the side drums 24 may be freely expanded and contracted, and the other may be a drum having the same diameter as the diameter of the central drum 22 that has been expanded. That is, the side drum 24 with respect to the central drum 22 has a diameter relationship between the side drum 24 and the central drum 22 after the diameter expansion in the second embodiment shown in FIG. 22 and the side drum 24) are rotated by a drive mechanism (not shown) (S301). The ribbon rubber 12 extruded from the die of the rubber extruder 10 (FIG. 1) is spirally wound around the rotating molding drum 20. Thus, the unvulcanized flap 34 having the cross-sectional shape shown in FIG. 4B is formed (S302).

Thereafter, the reinforcing rubber member 40 is attached to the valve mounting position of the unvulcanized flap 34 by pasting or the like (S303). Next, the diameter of one side drum 24 is reduced to the same diameter as that of the central drum 22, and the formed unvulcanized flap 34 is removed from the forming drum 20 (S304).
Next, the unvulcanized flap 34 is put into a split mold and vulcanized (S305), and the product flap 30 is formed.

  According to the third embodiment, since the unvulcanized flap 34 can be formed directly without forming the flap material in the first and second embodiments, the process becomes simpler and the working efficiency is high. There is an advantage of becoming.

Next, a fourth embodiment will be described.
In the fourth embodiment, in the third embodiment, at least one of the side drums 24 can be expanded and contracted, but unlike this, neither the central drum 22 nor the side drum 24 is provided with an expansion / contraction mechanism. The diameter is fixed. The other points are the same as those of the third embodiment.
That is, as in the third embodiment, the molding drum 20 has a cylindrical shape with the central portion constricted, and is disposed adjacent to the small-diameter central drum 22 and the central drum 22 along the rotation axis thereof. It consists of large-diameter left and right side drums 24 and is rotatably supported on a common rotating shaft by a drive mechanism.
In addition, since the shaping | molding process of the unvulcanized flap 34 by this shaping | molding drum 20 is the same as 3rd Embodiment, the description is used here and it abbreviate | omits. However, when the unvulcanized flap 34 is removed from the molding drum 20 after molding, since the diameters of the central drum 22 and the side drum 24 are both fixed, for example, the elasticity of rubber is used as it is from one side drum. Try to pull it out.

Although the embodiments of the present invention have been described above, according to these embodiments, the rubber material to be attached to the molding drum 20 is not vulcanized with a high viscosity from a die matched to the cross-sectional shape of the flap 30 as in the past. Instead of extruding rubber as a band and winding this band around the molding ring in a ring, ribbon rubber 12 extruded from the die of the rubber extruder 10 is spirally wound around the molding drum 20 and laminated. The flap material 32 is formed as a body (in this case, for example, using a stitching roller, the ribbon rubber 12 to be laminated and wound is appropriately pressed against the molding drum 20 and joined together).
Therefore, unlike the prior art, it is not necessary to add a processing step to make both end portions in the width direction of the annular strip material less than 0.5 mm before or after vulcanization, and the sharp edge of the flap 30 Can be molded according to the specifications (here, 0.5 mm or less).

  In addition, in this embodiment, since the top tread manufacturing equipment is not shared as in the prior art, there is no restriction due to gauge differences from the top tread, and there is no variation due to machine number differences in the manufacturing equipment, and the necessary accuracy is provided. The flap 30 can be easily obtained. Further, since a method of laminating and molding the unvulcanized flap 34 using the ribbon rubber 12 is adopted and the molding is completed before vulcanization, the product variation of the flap 30 can be reduced without requiring an additional process. It can be reduced to the same as the product variation of tires.

Further, according to the present embodiment, the ribbon rubber 12 is molded for the problem that the adjustment of the extrusion process and the jig / tool are necessary for the cross-sectional area adjustment mentioned in the problem (3) (i). Since the unvulcanized flap 34 is formed by spirally winding and laminating on the drum 20, it is not necessary to set the length of the dough based on the inner diameter of the mold as in the prior art. No extrusion process settings or tools are required.
With respect to the problem of the fixed length cutting equipment mentioned in the above problem (3) (ii), according to the present flap manufacturing method, it is directly connected from the extrusion process of the ribbon rubber 12 to the molding process of the unvulcanized flap 34. In order to do so, there is no need to provide a fixed length cutting facility.

Even when the problem (3) (iii) described above occurs when the material weight is outside the center value standard, the weight per unit length is measured and the ribbon rubber 12 is wound around the molding drum 20. The weight of the unvulcanized flap 34 can be adjusted by adjusting the stacking length.
In the conventional flap manufacturing method mentioned in the above problem (3) (iv), since the dough is thick, a long water tank is required to cool to the inside, and the ribbon rubber 12 is used immediately after extrusion. There is no need to do.
For the points that need to be managed for the preservation of the dough mentioned in the above problem (3) (v), the extruded dough is wound around the molding drum 20 and used as it is, so there is no need to store the dough, Therefore, it is not necessary to manage for storage.

Although the novel flap manufacturing method according to this embodiment has been described above, another flap manufacturing method that is not an embodiment of the present invention will be described for reference.
In this flap manufacturing method, as shown in FIG. 9, the dough 100 extruded from a rubber extruder (here, a cold tuba) 130 is wound around a rotating body 140 such as a drum as it is. However, in this case, unlike the embodiment, the dough 100 is wound spirally without being stacked.

  When the dough 100 is wound, the rotating body 140 is rotated by a driving device such as a motor (not shown) in synchronization with the extrusion of the dough 100. The rotational speed of the rotating body 140 can be changed by changing the rotational speed of the motor, for example. The rubber extruder 130 is configured to be movable in the axial direction of the rotating body 140 in synchronization with the rotation of the rotating body 140. These mechanisms are already well known.

In the above configuration, the extrusion speed of the dough 100 of the rubber extruder 130 and the rotation speed of the rotating body 140 are synchronized, and the extruded dough 100 is overlapped by moving the rubber extruder 130 in the axial direction of the rotating body 140. The rotating body 140 is spirally wound so that it does not become. In this case, the rubber extruder 130 extrudes the dough 100 by a length corresponding to the required preparation weight and winds it around the rotating body 140.
That is, the rubber extruder 130 moves in the axial direction of the rotating body 140 while extruding the dough 100 having a constant extrusion speed and a constant width and in synchronization with the rotation of the rotating body 140. The rotating body 140 rotates in synchronization with the extrusion speed of the dough 100 and winds the extruded dough 100 in a spiral shape.

  After the dough 100 is wound around the rotating body 140 by a predetermined amount, the dough 100 is pulled out from the winding start end side. This withdrawal is performed manually as a simple method. The pulled out fabric 100 is wound around the middle mold 110c in the lower mold 110b of the vulcanizing mold 110 as it is.

The dough 100 immediately after winding is heated. While the dough 100 is wound around the rotating body 140, the dough 100 is simultaneously pulled out (rewinded) manually from the winding end in synchronism with the winding, and the vulcanization mold 110 may be wound around the middle mold 110c. Further, when the fabric 100 is pulled out from the rotating body 140, the rotating body 140 may be rotated by a driving device.
Alternatively, the rubber extruder 130 may be fixed, and the rotating body 140 may be rotated relative to the rubber extruder 130 and moved in the axial direction in synchronization therewith.

FIG. 10 is a cross-sectional view showing a state in which the dough 100 is charged into the vulcanizing mold 110.
As shown in the figure, the dough 100 is wound around four rounds in the example shown between the lower mold 110b and the upper mold 110a. The upper mold 110a is lowered while the dough 100 is accommodated in the lower mold 110b. Subsequent processes are the same as in the prior art, and will not be described. However, the dough (rubber) 100, which has collapsed by lowering the upper mold 110a, is flowed in the vulcanizing mold 110, molded, heated to a predetermined temperature and heated. The product flap 120 can be produced by vulcanization.

According to this flap manufacturing method, the rubber extruder 130 can cope with the manufacture of flaps of different sizes by changing the length of the extruded dough 100 while keeping the dimensions of the dough 100 constant. In other words, for example, a radial tire flap for trucks and buses can be manufactured with relatively small equipment.
Further, in this method, the dough 100 is wrapped around the middle mold 110c several times, so the problem of the above (1) is that the flow of rubber changes by changing the dosing position of the dough, up to the tip of the vulcanization mold. It is unlikely that rubber will not flow.

  In addition, since the flap manufacturing method is performed using the dedicated flap equipment, there are no restrictions on the equipment listed as the problem (2), and other restrictions listed as the problem (3). Among these, for the problem that the adjustment of the extrusion process and jigs and tools are necessary for the adjustment of the cross-sectional area mentioned in the above (3) (i), the dimensions of the dough 100 are set in common. Since it suffices to wrap around the middle mold 110c, it is not necessary to set the length of the dough 100 based on the inner diameter of the vulcanizing mold 110. Therefore, unlike the prior art, setting of extrusion process for each size and tools are not required.

  For the problem of the constant length cutting equipment mentioned in (3) and (ii) above, according to the manufacturing method of this flap, since it is directly connected from the extrusion process of the dough 100 to the vulcanization process, it is necessary. It can be a process of extruding the dough as much as necessary. Further, by changing the shape of the die of the rubber extruder 130 and making the extruded shape of the dough 100 into a plate shape, for example, it can be managed on the rotating body 140 by reel winding as it is.

The problems mentioned in the above (3) and (iii), and the problem when the standard value of the fabric weight is out of the standard, are also measured because the weight per unit length of the fabric 100 is measured during the execution of this method. By adjusting the thickness, the charge weight to the vulcanization mold 110 can be adjusted, which can be eliminated.
Since the conventional dough mentioned in (3) and (iv) is thick, the problem that a long water tank is required to cool to the inside is because the dough is used immediately after extrusion in the manufacturing method of this flap. It is not necessary to cool.
For the problems mentioned in (3) and (v) above, that is, the problem that management is necessary to preserve the dough, the extruded dough is wrapped around a cylindrical body and used as it is, so it is necessary to store the dough Therefore, there is no need to manage.

Furthermore, according to the reference example, since the tire extrusion process is not used as in the prior art, processing costs in the conventional extrusion process can be reduced.
Moreover, according to this flap manufacturing method, as described above, since the dough 100 need not be stored, the dough storage area can be reduced. By using an integrated manufacturing facility from extrusion to vulcanization for flaps, it is possible to obtain advantages such as being able to be installed by completely separating the distribution and layout from the conventional tire manufacturing process.

  DESCRIPTION OF SYMBOLS 10 ... Rubber extruder, 12 ... Ribbon rubber, 20 ... Molding drum, 22 ... Center drum, 24 ... Side drum, 25 ... Pressure roller, 26 ... Cover member, 30 ... Flap, 32 ... Flap material, 32a ... Center part, 32b ... Taper part, 32c ... Tip part, 34 ... Unvulcanized flap, 40 ... Reinforcing rubber member .

Claims (9)

An unvulcanized ribbon rubber wound and laminated on the molding drum by a molding drum comprising a central drum and side drums disposed on both sides of the central drum is adjacent to the central portion having a predetermined thickness and the central portion. A step of forming an unvulcanized flap provided with a tapered portion whose diameter is larger than that of the central portion, the tip portion being a sharp tip;
A step of attaching a reinforcing member to the valve attachment position of the molded unvulcanized flap;
Vulcanizing the unvulcanized flap provided with the reinforcing member;
The manufacturing method of the flap which has. It is a manufacturing method of the flap according to claim 1, Comprising:
The step of forming the unvulcanized flap is formed in a shape in which the tapered portion is bent radially outward according to a difference in diameter between the central drum and a side drum having a larger diameter than the central drum. A method for manufacturing a flap, comprising a step of forming an unvulcanized flap. A method of manufacturing a flap according to claim 2,
The step of forming the unvulcanized flap is performed by winding and laminating the unvulcanized ribbon rubber in a state where the central drum and the side drum have the same diameter, and then pressing the central portion of the unvulcanized ribbon rubber with a pressing roller. A method of manufacturing a flap, which is performed by reducing the diameter of the central drum by an expansion / contraction mechanism while pressing. A method of manufacturing a flap according to claim 2,
In the step of forming the unvulcanized flap, the unvulcanized ribbon rubber is wound and laminated in a state where the central drum and the side drum have the same diameter, and then the central portion of the unvulcanized flap is pressed with a pressing roller. A method for manufacturing a flap, which is performed by expanding the diameter of the side drum by an expansion / contraction mechanism while pressing. A method of manufacturing a flap according to claim 2,
The molding drum includes a central drum and side drums arranged on both sides of the central drum and having a diameter larger than that of the central drum.
The step of forming the unvulcanized flap is a flap manufacturing method in which the unvulcanized ribbon rubber is wound and laminated on the forming drum. A method for manufacturing a flap according to any one of claims 1 to 5,
The method of manufacturing a flap, wherein the vulcanizing step is a step of vulcanizing using a split mold. An unvulcanized flap manufacturing apparatus comprising: an unvulcanized ribbon rubber extruder; and a flap molding drum for laminating and winding ribbon rubber extruded from the unvulcanized ribbon rubber extruder,
The flap forming drum includes a central drum and side drums arranged on both sides of the central drum, and the side drum is manufactured so as to have a larger diameter than the central drum. apparatus. The unvulcanized flap manufacturing apparatus according to claim 7,
The unvulcanized flap manufacturing apparatus provided with an expansion / contraction mechanism for reducing the diameter of the central drum so that the diameter of the central drum is smaller than that of the side drum. The unvulcanized flap manufacturing apparatus according to claim 7,
The unvulcanized flap manufacturing apparatus provided with an expansion / contraction mechanism for expanding the diameter of the side drum so that the diameter of the side drum becomes larger than that of the central drum from the same diameter.

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