WO2006093227A1

WO2006093227A1 - Method and apparatus for producing air bladder for safety tire

Info

Publication number: WO2006093227A1
Application number: PCT/JP2006/303986
Authority: WO
Inventors: Toshiaki Matsushima; Yukitaka Okafuji
Original assignee: Bridgestone Corporation
Priority date: 2005-03-03
Filing date: 2006-03-02
Publication date: 2006-09-08
Also published as: JP5052335B2; JPWO2006093227A1

Abstract

A method and apparatus for producing an air bladder for safety tire in which poor bonding of a hoop reinforcement layer and damage of a tube can be prevented by bonding the tube and the hoop reinforcement layer without using a press bonding means. The apparatus (1) for producing an air bladder for safety tires comprises a forming drum (2) for holding an air-impermeable toroidal tube (3) fixedly from the inside, a means (5) for carrying a ring-like hoop reinforcement layer (4) onto the outer circumference of the molding drum (2), an air supply means (6) for expanding the tube (3) by filling it with air, and a plurality of restriction means (7, 8) for suppressing expansion of the tube (3) filled with air. The forming drum (2) and the restriction means (7, 8) are united to surround the tube (3) and the hoop reinforcement layer (4). The tube (3) is expanded by filling it with air, and the tube (3) is press bonded to the hoop reinforcement layer (4) with inner pressure, thus forming an air bladder.

Description

Specification

Manufacturing method and manufacturing device for pneumatic tire for safety tire

Technical field

[0001] The present invention relates to a method and an apparatus for manufacturing a pneumatic tire for a safety tire, and more specifically, a hoop reinforcement layer formed in a ring shape is joined to a crown portion of an air-impermeable tube. In particular, the present invention relates to a method and an apparatus for manufacturing a steel sheet, and particularly prevents the hoop reinforcement layer from being poorly bonded and the tube from being damaged.

Background art

[0002] Safety tires that can travel for a certain distance even in a run-flat state in which the tire internal pressure has suddenly decreased due to puncture or the like include reinforcing members such as reinforcing tubes, reinforcing rubbers, reinforcing belts, foams, Tires containing elastic bodies, cores, and the like have been known in the past, and in recent years, runflats that are housed inside safety tires and reduce the internal pressure of tires from the viewpoint of suppressing manufacturing cost and weight increase. In this state, a safety tire that contains a hollow tubular air bladder that expands and deforms as the tire internal pressure decreases and replaces the load from the tire has been widely used (for example, JP-A-2004-90808). No. publication). In such a pneumatic tire-containing safety tire, the internal pressure of the air bladder is generally higher than the internal pressure of the tire in order to rapidly expand and deform the air bladder when the internal pressure decreases. However, if a centrifugal force due to rolling of the tire acts in addition to this internal pressure difference, the air bladder expands and reaches the inner surface of the tire, which may rub against the inner surface of the tire and reduce durability. For this reason, in a pneumatic tire containing safety tire, a crown hoop reinforcement layer made of a rubber covered body of a cord or a nonwoven fabric and a rubber is disposed at the crown portion to increase the rigidity of the crown portion. Prevents expansion deformation during normal internal pressure.

[0003] Generally, in the manufacture of tires, while narrowing the leg width of a raw case made of beads, carcass, sidewalls, etc., air is supplied into the case to inflate the raw case, and a belt, A raw tire is formed by attaching a reinforcing layer made of tread or the like. However, because the raw case itself has high rigidity, the outer diameter of the raw case can be increased just by narrowing the foot width, and the reinforcing layer can be After pasting, it can be crimped by a crimping means such as a roll. . However, in the production of safety tire pneumatic bladders, the tubes do not have a reinforcing structure such as a carcass and are closed in an annular shape. The only way to expand the outer diameter is to supply air inside and expand it

. However, even if an attempt is made to press the hoop reinforcement layer against the tube using a crimping means after the hoop reinforcement layer has been applied, the tube itself is less rigid and the tube shape is not stable. Can not. To increase the accuracy of shell occupancy, force that can compensate for the lack of rigidity of the tube itself with the internal pressure of the tube.If air is continuously supplied to the tube, the tube will be excessively stretched particularly in the width direction and damaged. There is a case. To prevent this, even if a bladder or the like is placed on both sides of the tube to restrict excessive expansion in the width direction, it can be deformed in the radial direction. The part where the roll 101 is in contact with the part located on the opposite side of the center axis 103 of the tube 102 is biased to expand and deform. There is concern about breakage of the tube at the site. Furthermore, when pasting by such a method, since the crimping cannot be performed with a force larger than the internal pressure of the tube, there is a concern that the hoop reinforcing layer may be poorly joined.

[0004] In Japanese Patent Application Laid-Open No. 2002-144444, an inner pressure is supplied to the hollow portion of the vulcanized tube to expand it, and the outer peripheral surface portion is crushed into a substantially flat shape. A hoop reinforcement layer made of non-woven fabric is affixed, and then the tube is further expanded in a vulcanization mold to enhance the circumferential orientation of the hoop reinforcement layer fibers and to adhere to the inner surface of the mold to vulcanize the tube. A method of manufacturing a pneumatic tire tire for safety tires is described. Although this method has the advantage that the hoop reinforcement layer can be applied relatively accurately, it is necessary to expand the tube after the hoop reinforcement layer is applied. there were.

[0005] Further, a tube serving as a base for an air bladder is formed by winding a sheet-like member on a molding drum, joining the circumferential ends thereof to each other, and then bending both side portions, In general, they are formed by stacking the parts and joining them together. As a method of folding back both side portions of a component member that is wound around a molding drum, for example, in Japanese Patent Application Laid-Open No. 62-109630, a component member is sandwiched between a rubber bladder and a cylindrical body, and this is centered in the width direction. For A method is described in which a tire component is folded back around a bead by moving it with force. According to the powerful method, the manufacturing equipment can be relatively simple, so that the manufacturing cost can be reduced and the quality of the folded portion can be made good and uniform.

[0006] However, such a manufacturing method cannot be applied as it is to the manufacture of a tube serving as a base for an air bladder. This is because the tire component has a bead with relatively high rigidity, which can be folded back with high accuracy, while the tube serving as the base of the air bladder has such a configuration. This is because there is no part with high rigidity that is the starting point of folding, and the whole is flexible. For this reason, even if a tube serving as a base for an air bladder is manufactured using the manufacturing method described in Japanese Patent Application Laid-Open No. 62-109630, the folded length may vary or the folded portion may be wrinkled. As a result, the quality of the folded part deteriorates, so that the shape of the obtained tube may be non-uniform or the joints at both ends may be poor.

Disclosure of the invention

As described above, there are various problems in pressing the hoop reinforcing layer against the tube by the pressing means. Accordingly, an object of the present invention is to provide a pneumatic tire for a safety tire that can prevent the occurrence of defective joining of the hoop reinforcing layer and the breakage of the tube by joining the tube and the hoop reinforcing layer without using a crimping means. It is to provide a manufacturing apparatus and a manufacturing method.

[0008] In order to achieve the above object, a method for producing a pneumatic tire pouch for a safety tire according to the present invention includes a toroidal tube that is impermeable to air on a molding drum, and is formed into a ring shape. The hoop reinforcement layer is conveyed onto the outer periphery of the molding drum, the molding drum and a plurality of restraining means are combined to surround the tube and the hoop reinforcement layer, the tube is filled with air, and the tube is expanded, and the internal pressure is increased. The tube is pressed and bonded to the hoop reinforcing layer to form an air bladder.

[0009] In addition, the diameter of the hoop reinforcement layer is within the range of ± 5% of the diameter of the product air bladder, and the shoulder portion of the hoop reinforcement layer used in this manufacturing method is the shoulder portion of the product air bladder. It has a shape corresponding to the shape, and the tube is filled with air and the molding drum and a plurality of restraining means are combined, and a part of the restraining means is from the inside in the radial direction of the tube. It is preferable that they move toward the outside in the radial direction, merge with the molding drum and other restraining means, and vulcanize while keeping the diameter of the air bladder substantially the same. In particular, when the forming drum and the restraining means are combined, it is more preferable to define an internal space having a cross-sectional shape corresponding to the cross-sectional shape of the product air bladder. The “state in which the diameters are kept substantially the same” here refers to a state in which the diameter is kept within a range of ± 5% of the original diameter.

[0010] Further, in this manufacturing method, a cylindrical tube constituent member is placed on the tube molding main drum, and is positioned radially inside both ends of the tube molding main drum, and is expanded by air filling. At least both width end portions of the tube constituent member are placed on a bladder, a cylindrical body is disposed radially outside one width end portion of the placed tube constituent member, and the one width end portion is placed. The placed bladder is filled with air and expanded, lifted in the direction of expanding one width end, and the expanded bladder and the cylindrical body sandwich one width end of the tube component, and the cylindrical body Is moved to the inside of the tube molding main drum in the width direction with one width end of the tube constituent member being sandwiched, and the bladder is deformed so as to be wound around the end of the tube molding main drum. of Folding one width end of the tube component starting from the section, pulling the air out of the bladder and reducing it, and moving the cylinder to the outside in the radial direction of the other width end of the mounted tube component Then, the bladder on which the other width end portion is placed is filled with air and expanded, and the other width end portion is lifted and expanded in the direction to expand the other end of the tube constituent member by the expanded bladder and the cylindrical body. The cylindrical body is moved inward in the width direction of the tube molding main drum with the other width end of the tube constituent member being clamped, and the bladder is wound around the end of the tube molding main drum. The tube width of the tube component is folded back from the end of the tube forming main drum, and the other width end is stacked on one width end of the tube component. Both width ends of member Preferably it includes that form a toroidal tube by bonding to each other.

[0011] In this case, the tube constituent member is fixedly held from the inside by holding means provided at both ends of the tube molding main drum, and both sides of the tube molding main drum and the tube molding main drum are fixed. A pair of tube-molding sub-driers with the same outer diameter After the sheet-like tube component is wound around the tube to form a cylindrical shape, the tube forming sub-drum is moved in the width direction of the tube forming main drum so that both width ends of the tube component are mounted on the bladder. It is preferable that the cylindrical body can be expanded and contracted.

[0012] Then, the safety tire pneumatic apparatus according to the present invention includes a molding drum for fixing and holding an air-impermeable toroid-shaped tube from the inside thereof, and a loop reinforcement formed in a ring shape. A conveying means for conveying the layer on the outer periphery of the molding drum; an air supply means for filling the tube with air and expanding; and a plurality of restraining means for suppressing expansion of the tube filled with air; The molding drum and the plurality of restraining means are combined to surround the tube and the hoop reinforcing layer.

[0013] Further, the molding drum and the plurality of restraining means are combined to define an internal space having a cross-sectional shape corresponding to the cross-sectional shape of the product air bladder, and the restraining means is provided on both sides of the tube. It is preferable to include an expansion / contraction restraining means that is positioned and capable of expanding and contracting in the radial direction of the molding drum, and that the transporting means includes a part of the restraining means.

[0014] Further, the manufacturing apparatus further includes an apparatus for manufacturing a toroidal tube by folding back both end portions of the cylindrical tube constituent member and then joining them together. The apparatus is located on the radially inner side of both end portions of the tube forming main drum on which the tube constituent member is placed, and expands by air filling to expand the width end portion of the tube constituent member. A pair of bladders that are lifted in the direction, a cylindrical body that is located radially outside the placed tube constituent member and sandwiches the wide end of the tube constituent member together with the expanded bladder, and the cylindrical body is connected to the tube constituent member. It is preferable to include moving means for moving the tube forming main drum to the inner side in the width direction with the width end portion sandwiched so as to fold back the width end portion of the tube constituent member.

[0015] In this case, the tube molding main drum is provided with holding means for fixing and holding the portion that becomes the fold-back base point of the tube constituent member from the inside at both ends, and on both sides of the tube molding main drum. It is preferable to further include a pair of tube molding sub-drums having the same outer diameter and capable of moving in the width direction of the tube molding main drum, and that the cylindrical body can be expanded and contracted. . Brief Description of Drawings

[FIG. 1] FIG. 1 is a cross-sectional view schematically showing a typical apparatus for producing a pneumatic tire for a safety tire according to the present invention.

FIG. 2 is a diagram for explaining a process of forming an air bladder using the apparatus shown in FIG. 1.

FIG. 3 is a diagram for explaining a process of forming an air bladder using the apparatus shown in FIG. 1.

[FIG. 4] FIG. 4 is a diagram for explaining a process of forming an air bladder using the apparatus shown in FIG.

[FIG. 5] FIG. 5 is a cross-sectional view showing a process of attaching a shoulder portion of a hoop reinforcing layer used in the present invention.

FIG. 6 is a cross-sectional view showing the change before and after applying the internal pressure of the tube used in the present invention.

[FIG. 7] FIG. 7 is a cross-sectional view schematically showing another device for producing a pneumatic tire bladder according to the present invention.

FIG. 8 is a diagram for explaining a process of forming an air bladder using the apparatus shown in FIG.

FIG. 9 is a cross-sectional view schematically showing still another pneumatic tire manufacturing apparatus for safety tires according to the present invention.

[FIG. 10] FIG. 10 is a side view showing an outline of a typical toroidal tube manufacturing apparatus according to the present invention, and shows an essential part thereof in cross section.

FIG. 11 is a partial cross-sectional side view for explaining a process for manufacturing a toroidal tube using the tube manufacturing apparatus shown in FIG.

12 is a partial cross-sectional side view for explaining a process for manufacturing a toroidal tube using the tube manufacturing apparatus shown in FIG.

FIG. 13 is a partial cross-sectional side view for explaining a process for manufacturing a toroidal tube using the tube manufacturing apparatus shown in FIG.

[FIG. 14] FIG. 14 shows the production of a toroidal tube using the tube production apparatus shown in FIG. It is a partial cross section side view for demonstrating the process to be.

15] FIG. 15 is a partial cross-sectional side view for explaining a process of manufacturing a toroidal tube using the tube manufacturing apparatus shown in FIG.

FIG. 16 is a partial cross-sectional side view for explaining a process for producing a toroidal tube using the tube production apparatus shown in FIG.

17] FIG. 17 is a side view schematically showing another toroidal tube manufacturing apparatus according to the present invention, and shows a cross section of the main part thereof.

FIG. 18 shows a state where the tube forming sub drum of the apparatus shown in FIG. 17 is retracted. FIG. 19 is a cross-sectional view showing the deformation of the tube when the tube is pressed by the crimping means in the conventional manufacturing method.

20] FIG. 20 (a) is a cross-sectional view of a main part of a conventional folding device for a tire component, and FIG. 20 (b) shows a tube component using the folding device shown in FIG. 20 (a). It is sectional drawing of the principal part at the time of folding up.

Explanation of symbols

1 Pneumatic production equipment

2 Molding drum

3 tubes

4 Hoop reinforcement layer

5 Transport means

6 Air supply means

7, 8, 13, 14 Restraint

9 Air bag

10 Sub-molding drum

11 Stitch Yarrow

12 Shoulder part of hoop reinforcement layer

21 Tube molding main drum

22a, 22b End of tube forming main drum

23a, 23b Blada 24 cylinder

25 means of transportation

29 Tube components

30a, 30b Wide end of tube component

31 tubes

32a, 32b Tube forming secondary drum

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a cross-sectional view schematically showing a typical apparatus for producing a pneumatic tire for a safety tire according to the present invention, and FIGS. 2 to 5 illustrate a process of forming an air bladder using the apparatus shown in FIG. It is a figure for doing.

A manufacturing apparatus 1 shown in FIG. 1 includes a molding drum 2. An air-impermeable toroidal tube 3, which is a component of an air bag for safety tires, is attached to the molding drum 2, and is fixedly held from the inside. This fixing and holding can be performed, for example, by slightly expanding the diameter of the molding drum 2. The manufacturing apparatus 1 further includes a conveying means 5 that conveys the hoop reinforcing layer 4 formed in a ring shape by a drum or the like (not shown) onto the outer periphery of the molding drum 2. Although not shown in the drawings, the transport means ₅ includes a holding means for expanding and contracting the segments by an air cylinder, a motor, or the like, in order to hold the hoop reinforcing layer 4 in a detachable manner. Further, the manufacturing apparatus 1 includes an air supply means 6 such as an air compressor for filling the tube 3 with air via an air filling valve (not shown) of the tube 3. Furthermore, the manufacturing apparatus 1 includes a plurality of restraining means 7 and 8 that suppress the expansion of the tube 3 filled with air. These restraining means 7 and 8 are movable in at least one direction, and after the hoop reinforcing layer 4 is transported to a predetermined position, it is united with the forming drum 2 to surround the tube 3 and the hoop reinforcing layer 4. . The material constituting the restraining means 7 and 8 is not particularly limited, and metals and plastics can be used. However, it is necessary that the material be a high-rigidity material with little deformation even when internal pressure is applied to the tube 3. . Although not shown, the restraining means may be divided not only in the width direction as shown in FIG. 1, but also in the circumferential direction like a sector molding for tire molding.

[0020] Next, a method of manufacturing an air bladder using the manufacturing apparatus 1 configured as described above will be described. I will explain. First, as shown in FIG. 1, the tube 3 is attached to the molding drum 2 and held securely. As the tube 3, either a vulcanized tube or an unvulcanized tube can be used depending on the heat resistance of the hoop reinforcing layer 4 and the bonding method between the hoop reinforcing layer 4 and the tube 3. The hoop reinforcement layer 4 can be made of a material having high extensibility in the circumferential direction such as a non-woven fabric / rubber composite, but a material having low extensibility in the circumferential direction, such as a cord / rubber composite. For example, it can be configured by spirally winding. In particular, it is preferable to use the latter from the viewpoint of suppressing creep deformation of the air bladder in a state where it is housed in a tire and an internal pressure is applied. When installing the tube 3, an air filling valve (not shown) is connected to the air supply means 6. Next, the transport device 5 is moved to transport the hoop reinforcement layer 4 onto the outer periphery of the molding drum 2 as shown in FIG. Next, the molding drum 2 and the restraining means 7 and 8 are combined to surround the tube 3 and the hoop reinforcing layer 4 as shown in FIG.

In this state, when the tube 3 is filled with air using the air supply means 6 and the tube 3 is expanded, the tube 3 is against the hoop reinforcement layer 4 by the internal pressure as shown in FIG. Pressed. When this state is maintained for several seconds to several minutes, the tube 3 and the hoop reinforcing layer 4 are joined to each other, and an air bladder 9 having a hoop reinforcing layer at the crown portion of the tube is obtained. The obtained air bladder 9 is removed from the molding drum 2 using the conveying means 5 and the like, and is subjected to post-treatment such as vulcanization treatment as necessary. When vulcanization is required, it can be performed according to the following procedure, for example. First, the air filled in the tube is discharged through the air filling valve, and the tube with the hoop reinforcement layer is contracted. This is stored in a vulcanization mold, and air is again filled into the tube via an air filling valve. At this time, in the same manner as in the conventional method for producing air bladder, the diameter of the tube with the original hoop reinforcement layer which can be expanded to a diameter larger than the diameter of the tube with the original hoop reinforcement layer is substantially the same. You can inflate to the diameter. In particular, when using a low-stretch hoop reinforcing layer, the latter is preferable. Next, heat is applied to the vulcanization mold to cause a vulcanization reaction.

[0022] If the air bladder is formed in this way, the tube 3 and the hoop reinforcing layer 4 are surrounded by the molding drum 2 and the restraining means 7 and 8, so that the tube can be obtained even when a high internal pressure is applied. There is no excessive expansion and damage. In addition, since bonding is performed without using a crimping means such as a roll, the tube 3 can be attached accurately without being biased in the negative direction. wear. Furthermore, since the expansion amount of the tube 3 is limited by the restraining means 7 and 8, it becomes possible to increase the internal pressure of the tube 3 without considering the expansion limit pressure, and the tube 3 and the hoop reinforcement layer 4 The pressure required for joining can be easily achieved. Furthermore, this invention can be used when a hoop reinforcement layer is applied to a vulcanized tube and when a low-extension hoop reinforcement layer is applied to an unvulcanized tube. Compared to the manufacturing method, there are few restrictions on the tube and hoop reinforcement layer. In order to increase the bonding force, a known bonding means such as an adhesive or a double-sided tape can be interposed between the tube 3 and the hood reinforcing layer 4.

[0023] As described above, in the manufacturing method according to the present invention, either a high-extension material or a low-extension material can be used as the hoop reinforcement layer. It is suitable for the production of a reinforcing layer having a low elongation material force, which has been difficult, in particular, an air bladder having a hoop reinforcing layer having a diameter within a range of ± 5% of the diameter of the product air bladder. This is because it is not necessary to greatly expand the diameter of the tube and the hoop reinforcement layer in the production.

[0024] When the molding drum 2 and the restraining means 7 and 8 are combined, it is preferable that the cross-sectional shape of the internal space defined by them be a shape corresponding to the cross-sectional shape of the product air bladder. This is because there is almost no change in shape between joining and use, and the accuracy of the position where the hoop reinforcing layer 4 is attached is further improved.

[0025] Further, when the hoop reinforcing layer 4 is wide and reaches the shoulder portion of the tube 3, for example, as shown in FIG. 5, on the sub-molding drum 10 for forming the hoop reinforcing layer 4, It is preferable to attach the shoulder portion 12 of the hoop reinforcement layer 4 in advance to a shape corresponding to the shape of the shoulder portion of the product air with a texture roll 11 or the like. This is also because the accuracy of the attaching position of the hoop reinforcing layer 4 is further improved.

[0026] When the inner pressure is applied to the tube 3 to cause expansion deformation, the width of the tube 3 is as follows before applying the inner pressure (shown by a solid line) and after applying the inner pressure (shown by a broken line) as shown in FIG. ) Narrows mainly due to expansion in the radial direction. For this reason, it may be difficult to surround the tube 3 by the restraining means 7 that restrains the expansion of the tube 3 in the width direction. Therefore, while the tube 3 is filled with air and expanded in the radial direction, the restraint means 7 is moved to form the molding drum 2 and the like. If they are combined, the tube 3 can be easily enclosed, which is preferable. Alternatively, as shown in FIGS. 7 and 8, a part of the restraining means is located on both sides of the tube 3 and is used as the expansion / contraction restraining means 13 capable of expanding and contracting in the radial direction of the molding drum 2. When fixing tube 3 to molding drum 2 of tube 3, position the tube 3 radially inward of tube 3, move it radially outward after fixing, and push tube 3 radially outward. Alternatively, the molding drum 2 and other restraining means 14 may be combined. Further, by combining these, the expansion / contraction restraining means 13 may be moved radially outward while filling the tube 3 with air.

Furthermore, as shown in FIG. 9, it is preferable that the conveying means 5 is configured to include a part of the restraining means. With this configuration, since the transportation from the hoop reinforcement layer 4 to the joining to the tube can be performed consistently by the transportation means 5, the manufacturing efficiency is improved.

[0028] Although not shown in the figure, generally a pneumatic device such as a rotating means for rotating the molding drum 2, a conveying means 5 and a driving means for driving the restraining means 7, 8, 13, 14 is used. It goes without saying that the components necessary for manufacturing are the same as those used in the conventional apparatus for forming an air bladder.

[0029] The toroidal tube may be a pre-molded tube, but the both end portions of the cylindrical tube structural member are arranged on the apparatus for producing a pneumatic tire bladder for safety according to the present invention. It is also possible to manufacture by joining each other after folding. Hereinafter, an apparatus for producing such a toroidal tube will be described.

FIG. 10 is a side view showing an outline of a typical toroidal tube manufacturing apparatus according to the present invention, and the main part thereof is shown in cross section. 11 to 16 are partial cross-sectional side views for explaining a process of manufacturing a toroidal tube using the apparatus shown in FIG.

[0031] The toroidal tube manufacturing apparatus shown in FIG. 10 includes a tube molding main drum 21, a pair of bladders 23a and 23b positioned radially inward of both end portions 22a and 22b of the tube molding main drum 21, and a tube A cylindrical body 24 having an inner diameter larger than the outer diameter of the molding main drum 21 and a moving means 25 for moving the cylindrical body 24 in the width direction of the tube molding main drum 21 are provided. The tube molding main drum 21 has the same structure as the molding drum used for the production of ordinary green tires. The tube forming main drum 21 is wound around the tube forming main drum 21 with a tube forming member formed in a cylindrical shape in advance by another forming drum or the like, or a sheet-like tube forming member. A tube constituent member formed in a cylindrical shape by joining the drum circumferential ends is placed. The bladders 23a and 23b have inner end portions in the drum width direction on the inner side in the drum width direction corresponding to the corresponding end portions 22a and 22b of the tube forming main drum 21, and outer end portions in the drum width direction on the tube forming main drum 21. It is located on the outer side in the drum width direction than the corresponding end portions 22a and 22b, and expands mainly toward the outer side in the drum radial direction by air filling. The cylindrical body 24 can be moved in the width direction of the tube forming main drum 21 by the moving means 25, and is stopped at an arbitrary position surrounding the main drum 21 and the bladders 23a and 23b from the outside in the radial direction, and at a position away from them. Is possible. For example, as shown in FIG. 10, the moving means 25 may be configured to run on a rail 26 installed on the floor surface in parallel with the width direction of the tube forming main drum 21 by a motor or the like. However, the present invention is not limited to this, although it may be configured to reciprocate with an air cylinder or the like provided. Further, in the illustrated example, the tube molding main drum 21 is connected to a rotating shaft 27 that rotatably supports the tube forming main drum 21, and the rotating shaft 27 is supported by a bearing 28.

Next, a method for manufacturing a toroidal tube using the manufacturing apparatus configured as described above will be described. First, as shown in FIG. 11, a cylindrical tube constituent member is placed on the tube molding main drum 21, and both width ends 30a, 30b of the tube constituent member 29 are placed on the bladders 23a, 23b, respectively. Put. Next, after the cylindrical body 24 is moved by the transfer means 25 and arranged on the radially outer side of one of the width end portions 30b of the tube constituent member 29, when the bladder 23b is filled with air and expanded, the width end portion 30b As shown in FIG. 12, the wide end 30b is sandwiched between the expanded bladder 23b and the cylindrical body 24. As shown in FIG. If the cylindrical body 24 is moved inward in the width direction of the tube molding main drum 21 in this state, the bladder 23a cannot adhere to and slide on the inner surface of the cylindrical body 24. Deformation moves between the drum 21 and the cylindrical body 24. For this reason, the width end portion 30b of the tube constituent member 29 moves toward the inner side in the width direction while being sandwiched between the bladder 23a and the cylindrical body 24. As a result, the tube constituent member 29 is gradually reversed and folded back. It is. At this time, as shown in FIG. 13, the bladder 23b is rolled over the end 22b of the tube forming main drum 21. Therefore, the one end portion 22b of the tube constituent member 29 is folded back starting from the end portion 22b of the tube forming main drum 21.

[0033] Subsequently, the bladder 23b is evacuated to reduce the size, and the cylindrical body 24 is arranged by the transfer means 25 and arranged on the radially outer side of the other width end portion 30a of the tube constituent member 29. When the container is filled and expanded, the width end portion 30a is lifted in the direction of expanding the diameter, and the expanded end bladder 23a and the cylindrical body 24 hold the width end portion 30a as shown in FIG. When the cylindrical body 24 is moved inward in the width direction of the tube forming main drum 21 in this state, the bladder 23a is deformed so as to be wound around the end portion 22a of the tube forming main drum 21, as shown in FIG. Starting from the end 22a of the molding main drum 21, the other width end 30a of the tube constituent member 29 is folded back and stacked on the width end 30b. Subsequently, the bladder 23a is evacuated and reduced, the cylinder 24 is retracted from the radially outer side of the tube constituent member 29 by the transfer means 25, and both width end portions 30a and 30b of the tube constituent member 29 are bonded with an adhesive or the like. When joined together, a toroidal tube 31 is formed. If it is necessary to avoid contact between the inner surfaces of the tube components 29 after folding, a sheet, liquid, solid agent, etc. that has a release effect contributes to the joining of the width end portions 30a and 30b. It is preferable to apply except for the part to be applied.

[0034] In the conventional method for turning back tire constituent members used in the production of green tires, as shown in Fig. 20 (a), the bladder 111 arranged on both sides of the molding drum 110 and the radially outer side are arranged. The tire constituent member 113 placed on the molding drum 110 is folded back by the cylindrical body 113. At this time, a bead 114 having a relatively high rigidity is arranged in the end region of the tire constituent member 113, and this is the starting point of the folding, so that the folding can be performed with high accuracy. However, if such a method is applied as it is to the manufacture of the tube that is the base of the air bladder, the force that does not exist in the tube constituent member as the starting point of folding is as shown in Fig. 20 (b). In addition, the position of the folded end of the tube constituent member 115 is not constant, the variation in the folded length is sufficient, and the folded portion is wrinkled. As a result, the quality of the folded portion may be deteriorated, resulting in a non-uniform shape of the tube or a joint failure at both width ends.

[0035] In contrast, in the method according to the present invention, the bladder is spread over the end portion of the tube molding main drum. Because the end of the tube molding main drum is always the starting point of folding by deforming it, even if it is a tube component that does not have a relatively rigid member such as a bead, the folded part This makes it possible to achieve good and uniform quality.

[0036] Further, the tube component member 19 can be fixedly held on the tube molding main drum 21 by various holding means, but particularly strong holding means are provided at both end portions 22a and 22b of the tube molding main drum 21, It is preferable to fix and hold the tube constituent member 29 from the inside. According to this, since the tube constituent member 29 does not lift from the tube molding main drum 21 at the time of folding, the starting point of the folding can be determined more accurately, and the folded portion of the tube constituent member 29 is wrinkled. This can be prevented more reliably. As the force and holding means, for example, a means can be used in which suction ports are provided at both end portions 22a and 22b and the tube constituting member 29 is adsorbed to the tube forming main drum 21 by connecting the suction ports to a vacuum pump.

[0037] Further, as the tube constituting member 29, a member formed in a cylindrical shape in advance may be used, but a sheet-shaped member may be wound around the tube forming main drum 21 to be a cylindrical shape. In this case, since there is a difference in diameter between the tube forming main drum 21 and the bladders 23a and 23b, the both end portions 30a and 30b of the tube constituent member 29 are satisfactorily soldered and end. It becomes difficult to join the parts. Therefore, as shown in FIG. 17, a pair of tube forming sub drums 32a having the same outer diameter on both sides of the tube forming main drum 21 and capable of moving the tube forming main drum 21 in the width direction, 32b is placed and the tube-shaped sub drums 32a and 32b are placed in the tube forming main drum 21 and the tube forming sub drums 32a and 32b by sprinkling sheet-like tube constituent members to form a cylindrical shape. By moving in the width direction of the drum 21, it is preferable to place both width end portions 30a, 30b of the tube constituent member 29 on the bladders 33a, 33b as shown in FIG. According to this, the manufacturing efficiency and manufacturing cost are greatly improved as compared with the case where the tube forming main drum 21 is transported and attached after being formed into a cylindrical shape with another forming drum, and the tube forming sub drums 32a, 32b are improved. Compared with the case where the tube forming member force is formed in a cylindrical shape on the tube forming main drum 21 and the bladders 23a, 23b, the tube forming member can be wound evenly, so that the accuracy of folding is improved. Will improve. [0038] Furthermore, as the tube constituent member 29, those having different thicknesses and materials depending on the size of the air bladder and the applied internal pressure are used. From the viewpoint of being able to respond to these various tube components in a short time without replacing parts, etc., the cylindrical body 24 is configured to be able to expand and contract, and according to the thickness and rigidity of the tube components. It is preferable to adjust the clearance between the bladders 23a and 23b. As a means for enabling the cylindrical body 24 to be enlarged or reduced in diameter, for example, the cylindrical body 24 is constituted by divided segments, and the segments are enlarged or reduced by an arm or a taper.

[0039] It should be noted that the above description only shows a part of the embodiment of the present invention, and various changes can be made within the scope of the claims. For example, in the illustrated embodiment, both the width end portions 30a, 30b of the tube component 29 need to be joined to each other, and therefore, the width ends 30a, 30b of the tube component 29 are sequentially connected by one cylindrical body 24. However, when joining both width end portions 30a, 30b via other members, two cylindrical bodies 24 and two moving means 25 are provided, and each width end portion 30a, 30b is provided. It's okay to go back at the same time. Further, in the illustrated embodiment, the force shown in the example in which the folding amounts of the both width end portions 30a and 30b of the tube constituent member 29 are uneven is equal, and both width end portions 30a are at the center of the tube width. 30b can be joined. In this case, the lengths of the bladder 23a and the bladder 23b may be different or the same as long as the both width end portions 30a and 30b can be joined. Further, when the cylindrical body 24 can be enlarged / reduced, it can be used as an apparatus for conveying the manufactured tube.

Industrial applicability

As is apparent from the above description, according to the present invention, the tube and the hoop reinforcement layer are joined without using the crimping means, thereby preventing the joint failure of the hoop reinforcement layer and the breakage of the tube. It has become possible to provide a manufacturing apparatus and a manufacturing method for a safety tire pneumatic bladder.

[0041] In addition, when forming both sides of a cylindrical tube constituent member to form a hollow circular tube, the starting point of folding can be determined with a relatively simple manufacturing facility, so that the manufacturing cost is low. In addition, it is possible to provide a manufacturing apparatus and a manufacturing method that can be folded back with high accuracy.

Claims

The scope of the claims

[1] Hold the air-impermeable toroidal tube on the molding drum,

A hoop reinforcement layer formed in a ring shape is conveyed on the outer periphery of the molding drum, the molding drum and a plurality of restraining means are combined to surround the tube and the hoop reinforcement layer, and the tube is filled with air to form a tube. Inflated,

A method for producing a pneumatic bladder for a safety tire, comprising forming a pneumatic bladder by pressing and joining a tube to a hoop reinforcing layer by internal pressure.

[2] The diameter of the hoop reinforcing layer is in the range of ± 5% of the diameter of the product air bladder.

The method for producing a pneumatic tire tire for safety tires according to 1.

[3] The method for producing an air bladder for a safety tire according to claim 1 or 2, wherein the shoulder portion of the hoop reinforcing layer has a shape corresponding to the shape of the shoulder portion of the product air bladder.

[4] The method for producing an air bladder for a safety tire according to any one of claims 1 to 3, wherein the molding drum and the plurality of restraining means are combined while the tube is filled with air.

[5] The part of the restraint means moves from the radially inner side to the radially outer side of the tube, and unites with the molding drum and other restraint means. The manufacturing method of the pneumatic tire for safety tires described.

[6] The production of a pneumatic tire for a safety tire according to claim 5, wherein the molding drum and the restraining means are combined to define an internal space having a cross-sectional shape corresponding to a cross-sectional shape of the product pneumatic bladder. Method.

[7] The method for producing a pneumatic tire for a safety tire according to any one of [6] to [6], wherein vulcanization is performed while keeping the diameter of the pneumatic bladder substantially the same.

[8] A cylindrical tube constituent member is placed on the tube forming main drum,

At least both width end portions of the tube constituent member are placed on a pair of bladders positioned on the radially inner side of both ends of the tube forming main drum and inflated by air filling, and one of the placed tube constituent members is placed. A cylindrical body is arranged on the outer side in the radial direction of the width end portion, and the bladder on which the one width end portion is placed is filled with air and expanded, and the one width end portion is lifted in the direction of expanding the diameter, One end of the tube constituent member is sandwiched between the expanded bladder and the cylindrical body, and the inner end of the tube forming main drum in the width direction with the cylindrical body sandwiching the one end of the tube constituent member. , And deform the bladder so that it wraps around the end of the tube forming main drum, and then turn back one end of the tube component from the end of the tube forming main drum.

Remove the air from the bladder and shrink it.

The cylindrical body is moved to the outside in the radial direction of the other width end of the placed tube constituent member, and the bladder on which the other width end is placed is filled with air and expanded, and the other width end is expanded. Lift in the direction

The other end of the tube constituent member is sandwiched between the expanded bladder and the cylindrical body, and the inner end of the tube forming main drum in the width direction is sandwiched with the other end of the tube constituent member. , The bladder is deformed so as to be wound around the end of the tube molding main drum, and the other width end of the tube constituent member is folded back starting from the end of the tube molding main drum.

Stacking the other width end on one width end of the tube component;

The method for producing an air bladder for a safety tire according to any one of claims 1 to 7, comprising forming a toroidal tube by joining both width end portions of the tube constituent members to each other.

9. The manufacturing method according to claim 8, wherein the tube constituent member is fixed and held from the inside by holding means provided at both ends of the tube molding main drum.

[10] The tube-forming main drum and the tube-forming main drum are located on both sides of the tube-forming main drum, and a pair of tube-forming sub-drums having the same outer diameter as above are rolled into a cylindrical shape by rolling sheet-like tube components. 10. After that, by moving the tube forming sub-drum in the width direction of the tube forming main drum, the both end portions of the tube constituent member are placed on the bladder. Manufacturing method.

[11] The method for producing an air bladder for a safety tire according to any one of [8] to [10], wherein the cylindrical body is capable of expanding and contracting.

[12] A molding drum that holds and holds the air-impermeable toroidal tube from the inside, A hoop reinforcement layer formed in a ring shape on the outer periphery of the molding drum; a supply means for filling the tube with air and expanding; and an expansion of the tube filled with air is suppressed. An apparatus for producing a pneumatic tire for a safety tire, comprising a plurality of restraining means, wherein the molding drum and the plurality of restraining means are combined to surround the tube and the hoop reinforcing layer.

13. The manufacturing apparatus according to claim 12, wherein the molding drum and the plurality of restraining means are combined to define an internal space having a cross-sectional shape corresponding to a cross-sectional shape of the product air bladder.

[14] The manufacturing apparatus according to claim 12 or 13, wherein the restraining means includes expansion / contraction restraining means that are located on both sides of the tube and capable of expanding / contracting in a radial direction of the molding drum.

[15] The manufacturing apparatus according to any one of claims 12 to 14, wherein the transport unit includes a part of the restraint unit.

[16] The apparatus further comprises a device for producing a toroidal tube by folding both width ends of the cylindrical tube component and joining them together.

The tube manufacturing apparatus is positioned on the radially inner side of both ends of the tube forming main drum on which the tube forming member is placed, and is expanded by air filling to expand the width end of the tube forming member. A pair of bladders that lift in the direction of expanding the diameter, a cylindrical body that is positioned radially outward of the placed tube constituent member and sandwiches the wide end of the tube constituent member together with the expanded bladder, and the cylindrical body 16. The moving device according to any one of claims 12 to 15, further comprising moving means for moving the tube forming main drum to the inner side in the width direction while sandwiching the width end portion of the constituent member and folding back the width end portion of the tube constituent member. The manufacturing apparatus according to one item.

17. The manufacturing apparatus according to claim 16, wherein the tube forming main drum includes holding means for fixing and holding a portion serving as a reference point for folding the tube constituent member from the inside at both ends thereof.

[18] The tube forming main drum further comprises a pair of tube forming sub drums on both sides of the tube forming main drum and having the same outer diameter and capable of moving in the width direction of the tube forming main drum. The manufacturing apparatus described in 1.

[19] The production according to any one of claims 16 to 18, wherein the cylindrical body is capable of expanding and contracting.

986C0C / 900Zdf / X3d 61 60 / 900Z OAV