JP4549170B2 - Pneumatic bladders and safety tires for safety tires - Google Patents

Description

  This invention is housed in a tire, filled with air at an internal pressure set in relation to a predetermined air pressure of the tire, and forms a space between at least the tire inner surface when the tire internal pressure is normal, The present invention relates to a hollow tubular safety tire air bladder for supporting a load from the tire, which is deformed with a decrease in the internal pressure of the tire, and a safety tire having such an air bladder, and particularly to improve recyclability. .

  Reinforcing members such as a reinforcing tube, reinforcing rubber, and reinforcing belt, or a foam, elastic body, medium, and the like as a safety tire that can travel a certain distance even in a run-flat state in which the tire internal pressure has suddenly decreased due to puncture or the like There are known tires that support the load of the tire on the shoulder, tires that are coated or filled with a sealant agent, block damaged parts such as holes formed in the tire, and prevent a decrease in internal pressure, and the like. In addition, these conventional safety tires have a complicated manufacturing method and are difficult to handle at the time of mounting. Recently, from the viewpoint of reducing the defective rate during manufacturing and improving manufacturing efficiency, In a run-flat state where the internal pressure of the tire is reduced and the internal pressure of the tire is reduced, a hollow circular air bladder that expands and deforms as the tire internal pressure is reduced and replaces the load from the tire is becoming widespread ( For example, see Patent Document 1). The air bladder maintains a space between the tire and the air bladder in a normal internal pressure state, while the outer surface of the tube is a support made of a composite of a nonwoven fabric and a rubber so that it can be rapidly expanded and deformed in a reduced internal pressure state. To obtain the desired modulus.

  In safety tires containing such air bladders, the tire part can be reused by repairing damaged parts such as puncture holes even after running in a run flat state, It cannot be reused and needs to be replaced with a new air bag. Since most of the air bags taken out by exchange are made of rubber with low recyclability, they are generally disposed of as industrial waste. Some of them are incinerated as fuel and thermally recycled. However, against the background of recent environmental problems, there is a strong demand to increase the material recycling rate with a lower environmental impact.

JP 2003-136923 A

  Accordingly, it is an object of the present invention to provide a safety tire air bladder and a safety tire that accommodates such air bladder, in which the use rate of renewable materials is increased and the recyclability is improved.

  In order to achieve the above object, the air bladder for a safety tire according to the present invention is housed in a tire and filled with air at an internal pressure set in relation to a predetermined air pressure of the tire, so that the internal pressure of the tire is normal. Is a hollow circular safety tire air bag that forms a space between at least the inner surface of the tire and expands and deforms as the internal pressure of the tire decreases to support the load from the tire. An impermeable tube, an annular support that tightly surrounds the entire outer surface of the tube, and a hoop reinforcement layer that surrounds the entire outer periphery of the crown of the annular support. A plurality of recyclable resin ring-shaped members extending in the radial direction are juxtaposed in the circumferential direction of the air bladder.

  In the present specification, the “predetermined air pressure” is an industrial standard effective in a region where tires are manufactured, sold, or used, such as JATMA, TRA, ETRTO, etc., for safety tires containing reinforced air bladders, It shall be the air pressure specified by the standard and specified according to the load capacity. The “internal pressure set in relation to the predetermined air pressure” means that a space is formed between the outer surface of the reinforcing air bladder and the inner surface of the tire in an air-filled state where the predetermined air pressure is applied to the tire. On the other hand, in the run-flat state where the internal pressure of the tire has decreased, the internal pressure of the reinforcing air bladder expands and deforms as the tire internal pressure decreases, and it can refer to the internal pressure that can replace the load support from the tire. Means an internal pressure larger than a predetermined air pressure, preferably a predetermined air pressure + 50% or less. Furthermore, “renewable resin” means a resin that can be recycled, and excludes a resin that can only be recycled.

  Further, the ring-shaped member is preferably formed by winding a ribbon-shaped member in the radial direction of the air bag and joining both ends thereof. In this case, it is preferable that the end of the ribbon-shaped member has a protrusion, and the both ends of the ribbon-shaped member overlapped by this protrusion are joined, and this protrusion is overlapped with the ribbon-shaped member. More preferably, it is a connecting member that penetrates both ends. More preferably, the connecting member is disposed at a position facing the rim in the tire storage state, and a gap is formed between the annular support and the rim.

  Furthermore, it is preferable that the annular support is formed by overlapping adjacent ring-shaped members in the circumferential direction to form an overlap portion. In this case, it is preferable that the overlap part of the ring-shaped member has a protrusion, and the overlap part is preferably joined by the protrusion, and the protrusion is a connecting member that penetrates the overlap part. More preferably.

  Furthermore, the annular support body has a plurality of protrusions at predetermined intervals at positions on two virtual circumferential lines separated in the width direction by substantially the same distance as the width of the hoop reinforcing layer. It is preferable that both width ends of the reinforcing layer are constrained by these protrusions. In this case, the protrusion is more preferably a restraining member that penetrates the annular support and extends radially outward at least by the same distance as the thickness of the hoop reinforcing layer. Here, “substantially the same distance as the width of the hoop reinforcement layer” means a distance at which the protrusions can effectively restrain the movement of the hoop reinforcement layer in the width direction, specifically, the width of the hoop reinforcement layer. The distance is in the range of 100 to 105% of the above.

  And the safety tire according to this invention has any of the above-mentioned air bladders.

  According to the present invention, it is possible to provide an air bladder for a safety tire and a safety tire that accommodates such an air bladder in which the usage rate of a renewable material is increased and the recyclability is improved.

  Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view in the width direction shown in a state where a typical safety tire containing a pneumatic bladder according to the present invention is mounted on a rim and filled with a predetermined internal pressure, and FIG. 2 is a run flat of the safety tire shown in FIG. FIG. 3 is a perspective view showing a state in which a part of the annular support constituting the safety tire air bladder shown in FIG. 1 is removed from the air bladder.

The air bladder 1 shown in FIG. 1 has a hollow circular tube shape and is housed in a tire 2 to form a safety tire 3. The safety tire 3 is mounted on the rim 4 to form a tire assembly. The tire 2 is filled with a predetermined air pressure, and the air bladder 1 is filled with air with an internal pressure set in relation to the predetermined air pressure of the tire 2. As a result, as shown in FIG. 1, a space S ₁ is formed in the tire 2, and a space S ₂ is formed in the air bladder 1. On the other hand, when the inner pressure of the space S ₁ of the tire 2 by puncture or the like is rapidly reduced, the internal pressure difference between the space S ₁ and the space S ₂ increases result, as shown in FIG. 2, the air bladder 1 is enlarged deformation Eventually, the inner surface 5 of the tire 2 is reached and the load is supported from the tire 2 by shoulder. The tire 2 and the rim 4 are not particularly limited, and various conventionally known structures can be used.

  The main features of the present invention are as follows: air bladder 1, air-impermeable tube 6, annular support 7 that tightly surrounds the entire outer surface of tube 6, and crown portion of annular support 7 And a hoop reinforcing layer 8 that surrounds the entire outer periphery of the ring, and as shown in FIG. 3, the annular support 7 has a reusable resin ring-shaped member 9 extending in the radial direction of the air bladder 1. There are two or more juxtaposed in the circumferential direction of No.1.

  The air bladder for safety tires is mainly composed of a tube and an annular support, and all of them have been made of rubber material, so that used air bladder has been disposed of as industrial waste. Among these members, the tube has physical properties that can be expanded and deformed instantaneously to the inner surface of the tire when the internal pressure of the tire decreases, and has high air impermeability in both the normal internal pressure state and the run flat state. From the viewpoint of satisfying these required performances and other performances such as weight, durability, productivity, and cost at the same time, rubber-based materials are the best at present. There is no material that can replace this. On the other hand, with respect to the annular support, in the normal internal pressure state, the shape of the air bladder is maintained to maintain the space between the air bladder and the tire. It is necessary to have physical properties that do not hinder the expansion deformation of the tube by stretching or breaking.

  The inventors have repeatedly studied the formation of this annular support with a recyclable material and have come to the idea of using a resin. In general, a resin behaves as a high-rigidity material having a low elongation rate in a low tension region, but has a characteristic that the elongation rate rapidly increases when a certain tension (yield strength) is exceeded. Also, the yield strength can be adjusted relatively easily by adjusting the thickness. Therefore, an annular support is formed using resin, and its yield strength is greater than the tension acting on the air bladder due to the internal pressure difference between the tire and the air bladder during normal running, and the air flow during run flat running If the tension is adjusted to be smaller than the tension acting on the air bladder in accordance with the internal pressure of the bladder, the diameter expansion of the air bladder can be suppressed in the normal internal pressure state, and the diameter can be expanded rapidly in the run-flat state. It can be done.

  However, if the annular support is simply formed of resin and vulcanized and bonded to the tube in the same manner as the conventional annular support made of a rubber-based material, both the tube and the annular support are separated at the time of disposal. In addition to the need for force, there is a concern that tube fragments may adhere to the separated annular support, which impedes material recycling of the annular support. Therefore, the inventors have further studied the application form of the annular support to the tube, and formed a resin with a predetermined width in a ring shape, and arranged a plurality of these in the circumferential direction of the air bladder to arrange the outer surface of the tube. If it is formed into an annular body that tightly surrounds the entire body, a high frictional force acts between the tube and the annular support body, so that both can be fixed without vulcanization bonding, and from the used air tank The inventors have found that the annular support can be easily separated and the recyclability can be improved, and the present invention has been completed. Furthermore, since the annular support is formed of resin, large equipment such as a rolling device, a cutting device, and a vulcanizing device, which were necessary when the annular support was formed of a conventional rubber-based material, is not necessary. Since the manufacturing process is also simplified, the energy required for manufacturing the air bladder is reduced, and the product has a low environmental impact not only during disposal but also during manufacturing.

  It should be noted that the tube 6 and the annular support 7 do not need to be adhered simply by being brought into close contact with each other, but there is a concern that the tube 6 and the annular support 7 may be displaced in the circumferential direction due to sudden acceleration and sudden deceleration. Alternatively, both may be bonded with an adhesive or a double-sided tape. Examples of the recyclable resin include a wide range of resins such as a styrene resin, an olefin resin, a vinyl chloride resin, and a polyester resin, but the viewpoint of satisfying other performances required for the annular support 7 at the same time. Is preferably an olefin resin and a polyester resin, particularly preferably polypropylene (PP) or polyethylene terephthalate (PET).

  4 is a cross-sectional view in the width direction of an annular support constituting another air bladder for a safety tire according to the present invention, and FIG. 5 is a side view of the connecting member shown in FIG. As shown in FIGS. 3 and 4, the ring-shaped member 9 is preferably formed by winding a ribbon-shaped member 10 in the radial direction of air and joining both end portions 11 thereof. According to this, since the ribbon-like member 10 is wound on the tube 6 that has been subjected to vulcanization molding, and finally the both end portions 11 are joined to form the ring-like member 9, the manufacturing process of the air bladder 1 is performed. In addition to simplification, only the ribbon-like member 10 can be easily separated by peeling off the joined end portions 11 at the time of disposal. As shown in FIG. 3, an adhesive, a double-sided tape, heat welding, or the like can be used for joining the both ends 11. However, a protrusion is provided on the end 11 of the ribbon-like member 10, and the protrusion It is preferable to join the both end portions 11 by locking each other. In particular, as shown in FIG. 4, it is preferable to use a connecting member 12 as a protruding portion and to penetrate both end portions 11 on which the ribbon-like member 10 is overlapped to join. This is because joining using such protrusions facilitates joining at the time of manufacturing the ribbon-like member 10 and peeling at the time of disposal. From the viewpoint of further improving the recyclability, it is more preferable that the connecting member 12 is made of a recyclable resin and collected at the time of disposal and recycled, or made of metal and collected at the time of disposal and reused.

  Further, from the viewpoint of securing the both end portions 11, the connecting member 12 has a ribbon-shaped member 10 having a diameter larger than that of the central portion at one end portion thereof as shown in FIG. 5. It is preferable to have a flange-shaped head portion 13 that can be formed. Further, as shown in FIG. 6, the connecting member 12 is disposed so as to be opposed to the rim 4 in the tire storage state, and the ribbon is so arranged that the head portion 13 is on the rim 4 side, for example. It is preferable to form a gap between the annular support 7 and the rim 4 by being fixed to the shaped member 10. In normal tires, the heat generated by bending deformation and rolling resistance of the tread is carried to the rim by the convection of air in the tire and is radiated from here, so the temperature in the tire does not rise extremely. . On the other hand, in tires that contain air bladders, the flow of air to the rim is hindered by the air bladders and heat dissipation from the rim is reduced, so the temperature inside the tire continues to rise, and finally the tires are removed. There is a possibility that the durability of the constituent members may be reduced. If a gap is formed between the annular support 7 and the rim 4 by the head portion 13 of the connecting member 12, the air flows in the gap, so that the amount of heat released from the rim 4 is secured and the temperature inside the tire is reduced. The rise can be suppressed.

  As shown in FIG. 3, the annular support 7 is preferably formed by overlapping the adjacent ring-shaped members 9 in the circumferential direction to form an overlap portion 14. The overlap portion 14 is formed when a gap exists between the adjacent ring-shaped members 9, and the tube 6 expanded by applying the internal pressure protrudes outward from the gap and is formed at the edge of the ring-shaped member 9. This is because the tube 6 may be damaged, so that the overlap portion 14 is formed to eliminate a gap between the adjacent ring-shaped members 9. FIG. 7 is a side view of the air bladder thus formed. Adhesive, double-sided tape, heat welding, or the like can be used for joining the overlap portion 14, but a protrusion is provided on the overlap portion 14, and the overlap portion 14 is locked to each other by the protrusion. And are preferably joined. In particular, as shown in FIG. 8, it is preferable to use a connecting member 15 as a protruding portion and to join through the overlapping portion 14. This is because, when such a protrusion is used for joining, joining at the time of manufacturing the ring-shaped member 9 and peeling at the time of disposal become easier. From the viewpoint of further improving the recyclability, it is more preferable that the connecting member 15 is made of a recyclable resin and collected at the time of disposal and recycled, or made of metal and collected at the time of disposal and reused.

  In addition, from the viewpoint of securing the overlapped portion 14, the connecting member 15 is omitted from illustration, but at least one end thereof, like the connecting member 12 used for joining the ribbon-like member 10, It is preferable to have a flange-shaped head portion that has a larger diameter than the central portion and can lock the ring-shaped member 9. Further, as shown in FIG. 9, the connecting member 15 is disposed so as to be opposed to the rim 4 in the tire storage state, and for example, a ring-like shape is formed such that the head portion as described above is on the rim 4 side. It is preferable to form a gap between the annular support 7 and the rim 4 by being fixed to the member 9. According to this, as a result of the air flowing in the gap, a heat radiation amount from the rim 4 is ensured, and an increase in temperature in the tire can be suppressed.

FIG. 10 is a top view of a portion of the air bladder 1 according to the present invention. As shown in FIG. 10, the annular support 7 has a predetermined interval at a position on _two virtual circumferential lines C ₁ and C ₂ that are substantially the same distance as the width of the hoop reinforcement layer 8 and are separated in the width direction. It has a plurality of projections 16, and both width ends 17, 17 of the hoop reinforcing layer 8 are preferably restrained by these projections 16, 16. According to this, since it becomes unnecessary to adhere the hoop reinforcement layer 8 to the annular support 7 in order to suppress the movement of the hoop reinforcement layer 8 in the width direction, the annular support 7 and the hoop reinforcement layer 8 are disposed at the time of disposal. Separation and collection can be easily performed, and the recyclability of the air bladder is further improved. The protrusion 16 may be formed integrally with the annular support 7. However, from the viewpoint of facilitating separation and collection at the time of disposal and disposal, the protrusion 16 penetrates the annular support 7 and extends radially outward. It is preferable to use a restraining member that extends at least the same distance as the thickness of the hoop reinforcing layer 8. As this restraining member, the thing of the same structure as the connection member mentioned above can be used.

  In addition, the place mentioned above only showed a part of embodiment of this invention, and can change a various change in a claim. For example, FIG. 1 and the like show an embodiment having one wide hoop reinforcing layer 8, but a hoop reinforcing layer may be formed by spirally winding a narrow ribbon-like member. Further, a protective layer wider than the hoop reinforcing layer is disposed on the outer periphery of the hoop reinforcing layer 8, or is made of vulcanized rubber or a thermoplastic resin between the air bladder 1 and the rim 4, and is formed in the tire space. Or a flap provided with an air flow passage that allows the air to flow to the rim.

  Next, a safety tire pneumatic bladder according to the present invention was prototyped and performance evaluation was performed, which will be described below.

  In a state filled with 70 kPa (relative pressure), the outer periphery of a vulcanized rubber tube having a width of 400 mm, an outer diameter of 800 mm, and an inner diameter of 575 mm has a shape as shown in FIG. 11, a width of 70 mm, a length of 960 mm, A ribbon-shaped member made of PET having a thickness of 0.7 mm and a breaking elongation of 100% is wound in the radial direction to form a ring-shaped member, which is connected in the circumferential direction. Specifically, the ribbon-shaped member was wound around the outer periphery of the rubber tube, and joined to the holes 18 at both ends through the connecting member. As a connecting member, it has a shape as shown in FIG. 5 and has a flange-like head portion with a diameter of 15 mm at one end, a diameter at the center is 5 mm, and a diameter at the other end is 7 mm. , 6 nylon was used. Further, the same connecting member was passed through the hole 19 and the hole 20 of the adjacent ring member, and the ring members were joined to each other. Further, the connecting member was used as a restraining member, passed through the hole 21, and after the annular support was completed, a hoop reinforcement layer was fitted between the restraining members. A protective layer made of a thermoplastic elastomer (TPE) having a thickness of 1.5 mm and an elongation at break of 200% was disposed on the outer periphery to obtain an air bladder of the example.

  For comparison, the same rubber tube as that used in the examples was used, and five layers of aramid non-woven fabric coated with rubber on the crown portion and one layer of PET non-woven fabric coated with rubber on the side portion and the base portion were each vulcanized and bonded. A prototype of an air bladder (conventional example) was also made.

(Durability test)
Each of the sample air bladders was accommodated in a tire having a tire size of 495 / 45R22.5 and mounted on a rim having a rim size of 17.00 × 22.5 to form a tire wheel. Next, an internal pressure of 970 kPa was applied to the tire wheel and 900 kPa was applied to the tire, and the drum tester was run at 50,000 km under conditions of a tire load of 56.88 km and a running speed of 60 km / h. As a result, the tires of both the example and the conventional example completed 50,000 km without any failure or expansion of the air bladder. Further, when the state of the air bladder in the tire wheel was confirmed with a CT scanner, no side bulge occurred and the initial shape was maintained. In addition, when the internal pressure in the tire side space of the tire wheel is gradually released, the air bladder expands substantially uniformly when the pressure in the tire becomes a predetermined value or less, and does not bulge on the inner surface of the tire. I was able to contact you. Therefore, it has been found that the air bladder according to the present invention exhibits at least the same performance as the conventional air bladder with respect to the basic characteristics required of the air bladder.

(Recyclability)
The mass of the air bladder of the example and the conventional example was measured. The tubes used for these were common and the weight was 12 kg. The mass of the air bladder excluding the tube is 6 kg in the example and 16 kg in the comparative example. In the conventional example, the total of 28 kg of the tube and other parts is treated as industrial waste, whereas in the example, 12 kg of the tube is treated as industrial waste. 6 kg can be recycled, and the recyclability is greatly improved. Further, in the case of the air bladder of the example, since the annular support was not vulcanized and bonded, removal and separation were easy.

  According to the present invention, it has become possible to provide a safety tire air bladder and a safety tire that accommodates such air bladder, in which the usage rate of renewable materials is increased and the recyclability is improved.

1 is a cross-sectional view in the width direction showing a state in which a typical safety tire containing a pneumatic bladder according to the present invention is mounted on a rim and filled with a predetermined internal pressure. FIG. 2 is a cross-sectional view in the width direction of the safety tire shown in FIG. 1 in a run-flat state. It is a perspective view which shows a part of annular support body which comprises the air bladder for safety tires shown in FIG. 1 in the state removed from the air bladder. It is sectional drawing of the width direction of the cyclic | annular support body which comprises the air bladder for other safety tires according to this invention. It is a side view of the connection member shown in FIG. FIG. 6 is a cross-sectional view in the width direction showing a state in which a safety tire containing another air bladder according to the present invention is mounted on a rim and filled with a predetermined internal pressure. It is a side view of the air bladder formed by juxtaposing ring-shaped members. It is a perspective view which shows a part of annular support body in the state removed from the air bladder. FIG. 6 is a cross-sectional view in the width direction showing a state in which a safety tire containing another air bladder according to the present invention is mounted on a rim and filled with a predetermined internal pressure. FIG. 6 is a top view of a part of another air bladder according to the present invention. It is an expanded view of a typical ribbon-shaped member.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Air bladder 2 Tire 3 Safety tire 4 Rim 5 Tire inner surface 6 Tube 7 Annular support body 8 Hoop reinforcement layer 9 Ring-shaped member 10 Ribbon-shaped member 11, 14 Overlap part 12, 15 Connecting member 13 Head part 16 of a connecting member Protrusion 17 Width end of hoop reinforcement layer 18, 19, 20, 21 hole

Claims (11)

The tire is housed in a tire and filled with air at an internal pressure set in relation to a predetermined air pressure of the tire. When the tire internal pressure is normal, a space is formed at least between the tire inner surface and the tire internal pressure. In the air bladder for a hollow circular safety tire that expands and deforms as it falls and replaces the load from the tire,
The air bladder comprises an air-impermeable tube, an annular support that tightly surrounds the entire outer surface of the tube, and a hoop reinforcement layer that surrounds the entire outer periphery of the crown portion of the annular support,
The annular support body is formed of a plurality of recyclable resin ring-shaped members extending in the radial direction of the air bladder in the circumferential direction of the air bladder.   2. The pneumatic tire for a safety tire according to claim 1, wherein the ring-shaped member is formed by winding a ribbon-shaped member in a radial direction of the air bladder and joining both ends thereof.   The air bladder for a safety tire according to claim 2, wherein an end portion of the ring-shaped member has a protruding portion, and both end portions of the ribbon-shaped member overlapped by the protruding portion are joined.   The pneumatic tire for a safety tire according to claim 3, wherein the protrusion is a connecting member that penetrates both ends of the ribbon-like member that are overlapped with each other.   5. The air bag for a safety tire according to claim 3, wherein the protrusion is disposed at a position facing the rim in a tire storage state, and a gap is formed between the annular support and the rim.   The said annular support body is the air bag for safety tires as described in any one of Claims 1-5 formed by making adjacent ring-shaped members overlap in the circumferential direction, and forming an overlap part.   The air bladder for a safety tire according to claim 6, wherein the overlap portion of the ring-shaped member has a protrusion, and the overlap is joined by the protrusion.   The safety tire air bladder according to claim 7, wherein the protrusion is a connecting member penetrating the overlap portion.   The annular support has a plurality of protrusions at predetermined intervals at positions on two virtual circumferential lines separated in the width direction at substantially the same distance as the width of the hoop reinforcement layer. Both the width | variety ends of these are restrained by these protrusion parts, The air bladder for safety tires as described in any one of Claims 1-8.   10. The air bag for a safety tire according to claim 9, wherein the protrusion is a restraining member that penetrates the annular support and extends radially outward at least by the same distance as the thickness of the hoop reinforcing layer.   A safety tire having an air bladder according to any one of claims 1 to 10.

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