JP4723330B2 - Pneumatic tire and rim assembly - Google Patents

Description

  The present invention relates to an assembly of a pneumatic tire and a rim in which a band-shaped sound absorber made of a sponge material is disposed in a tire lumen.

  As one of tire noises, there is road noise generated in a frequency range of about 50 to 400 Hz, and the main cause is known as resonance vibration of air (cavity resonance) occurring in the tire lumen. Therefore, in order to reduce such road noise, the present applicant, for example, as shown in FIG. 14, a tire in which a band-shaped sound absorber b made of a sponge material extending in the tire circumferential direction within the tire lumen a is arranged. And a rim assembly c have been proposed (see, for example, Patent Document 1). The noise control body b can convert vibration energy of air in the tire lumen a into heat energy, and can effectively suppress cavity resonance in the tire lumen a.

JP 2002-67608 A

  By the way, in the general market, such an assembly c is often stored in the state of a composite in which the sound control body b is bonded to the tire in advance. However, sponge materials, particularly ether-based polyurethane sponges, which are preferable as the sound control body b, tend to be inferior in light resistance such as being easily deteriorated by ultraviolet rays. Therefore, when the composite is stored, there is a problem that the sponge material, which is the sound control body b, is deteriorated by ultraviolet rays outdoors or indoors, and the required durability cannot be sufficiently exhibited.

  The present invention has been devised in view of the above circumstances, and is based on covering the surface of the sound damper with a protective layer made of a light-shielding resin film to prevent the sound damper from being deteriorated by exposure. An object of the present invention is to provide an assembly of a pneumatic tire and a rim that can sufficiently exhibit the durability required for a sound control body.

According to the first aspect of the present invention, a rim, a pneumatic tire mounted on the rim, and a tire lumen surrounded by the rim and the pneumatic tire are fixed and extend in the tire circumferential direction. A sound-absorbing member made of a sponge material having a volume of 0.4 to 20% of the total volume of the tire lumen, and an ultraviolet transmittance of 20 % Of a light-shielding resin film and a protective layer covering the surface of the sound absorber by being bonded to the surface of the sound damper via an adhesive, the adhesive comprising an isocyanate compound, and The resin film is made of a polyurethane resin .

According to a second aspect of the present invention, the sound control tool does not include the protective layer at both ends in the circumferential direction of the sound control body .
According to a third aspect of the present invention, a rim, a pneumatic tire attached to the rim, a belt-like restraint extending in the tire circumferential direction is fixed in a tire lumen surrounded by the rim and the pneumatic tire. The sound control tool includes a sound control body made of a sponge material having a volume of 0.4 to 20% of the total volume of the tire lumen, and a light shielding device having an ultraviolet transmittance of 20% or less. And a protective layer covering the surface of the sound damper by being bonded to the surface of the sound damper through an adhesive, and the sound damper is fixed to the inner surface of the tread, The noise damper has a bottom surface on the inner surface side of the tread and an upper surface facing the tire lumen, and in the tire meridian cross section including a tire shaft, the noise damper has a maximum thickness from the bottom surface to the upper surface. The value (tm) is in the range of 5 to 45 mm, and A laterally oblong cross-sectional shape in which the width (W1) of the surface is larger than the maximum value (tm) of the thickness, and the upper surface has a peak portion having the maximum value (tm) of the thickness, and the peak portion A wave element consisting of a valley bottom portion having a minimum thickness (ti) and an inclined portion extending from the mountain top portion to each valley bottom portion along a wave-like curve repeated in the width direction, Both ends of the upper surface in the width direction are terminated at the valley bottom portion or the inclined portion, and the thickness (te) from the bottom surface of the upper surface in the width direction is 1.0 to 15.0 mm. It is characterized by.
According to a fourth aspect of the present invention, the sound control tool does not include the protective layer at both ends in the circumferential direction of the sound control body .
The invention described in claim 5 is characterized in that the adhesive is made of an isocyanate compound and the resin film is made of a polyurethane resin .
According to a sixth aspect of the present invention, there is provided a pneumatic tire and a noise control body comprising a pneumatic tire and the sound damping device according to any one of claims 1 to 5 fixed to the inner surface of the tread of the pneumatic tire. And a complex.

Note that the volume of the sound damper is an apparent volume determined from the outer shape of the noise damper, and includes the volume occupied by the internal bubbles. Further, the “total volume of the tire lumen” is determined as a value V approximately obtained by the following equation (1) in a no-load state in which the assembly is filled with normal internal pressure.
V = A × {(Di−Dr) / 2 + Dr} × π (1)
In Formula (1), “A” is a tire lumen area obtained by CT scanning of the tire lumen in the normal state, and “Di” is a maximum outer diameter of the tire lumen in the normal state shown in FIG. , “Dr” is the rim diameter, and “π” is the circumference. In addition, “regular internal pressure” is the air pressure that each standard defines for each tire in the standard system including the standard on which the tire is based. The maximum air pressure for JATMA and the table “TIRE LOAD LIMITS AT for TRA” The maximum value described in “VARIOUS COLD INFLATION PRESSURES”. If ETRTO, “INFLATION PRESSURE”. However, when the tire is for a passenger car, the pressure is uniformly set to 200 kPa in consideration of the actual use frequency.

  In the present invention, the sound control device disposed in the tire lumen covers and protects the surface of the sound control body made of the sponge material with the protective layer made of the light shielding resin film. For this reason, it is possible to prevent the sound absorber from being deteriorated by ultraviolet rays, ozone, or the like even when the sound absorber is stored in a state of being attached to the tire in the market or the like. As a result, the durability required for the sound control body can be sufficiently exhibited while maintaining the effect of reducing road noise.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the pneumatic tire and rim assembly 1 according to the present embodiment includes a rim 2, a tire 3 attached to the rim 2, and a tire interior surrounded by the rim 2 and the tire 3. And a sound control device 4 disposed in the cavity i.

  The rim 2 has a well-known structure including an annular rim body 2a on which the bead portion 3b of the tire 3 is mounted, and a disk-shaped disk 2b for fixing the rim body 2a to the axle. In this example, the case where the regular rim prescribed | regulated by the said standards, such as JATMA, is illustrated.

  The tire 3 is a tubeless tire, and as shown in FIG. 3, a tread portion 3t, a pair of sidewall portions 3s extending inward in the tire radial direction from both ends thereof, and inner ends of the sidewall portions 3s. The tire inner surface 3i is covered with an inner liner made of low air permeable rubber. Thereby, an airtight tire lumen i is formed by the tire inner surface 3i and the rim inner surface 2i. Various tires can be applied as the tire 3 without being restricted by the internal structure or category. However, passenger car tires that are strongly required to be quiet in the passenger compartment, especially radial tires for passenger cars having a flatness ratio of 50% or less are preferably employed.

  The tire 3 is reinforced by a cord layer including a carcass 6 straddling between the bead portions 3b and 3b, and a belt layer 7 disposed radially outside the carcass 6 and inside the tread portion 3t.

  The carcass 6 is formed of one or more, for example, one carcass ply 6A in which organic fiber cords are arranged at an angle of, for example, 70 to 90 ° with respect to the tire circumferential direction. Both ends of the carcass ply 6 </ b> A are folded around the bead core 8. The belt layer 7 is formed of a plurality of, for example, two belt plies 7A and 7B in which steel cords are arranged at an angle of, for example, 10 to 40 ° with respect to the tire circumferential direction. The belt layer 7 is improved in belt rigidity by crossing steel cords between plies. Note that a known band layer or the like may be provided outside the belt layer 7 as necessary.

  Next, the sound control tool 4 includes a sound control body 10 made of a long band-like sponge material extending in the tire circumferential direction and a protective layer made of a light-shielding resin film and covering the surface of the sound control body 10. 11. The band-shaped sound control device 4 is bonded to the tire inner surface 3i or the rim inner surface 2i along the tire circumferential direction using a double-sided adhesive tape, an adhesive, or the like. As a result, the noise suppressor 4 is prevented from freely moving in the tire lumen i during traveling, preventing damage to the noise suppressor 4 and stably exhibiting the resonance suppression effect. In particular, it is preferable that the sound control device 4 is bonded to the tire inner surface 3i, particularly the tread inner surface 3ti, from the viewpoint of rim assembly. The tread inner surface 3ti means a surface of the tire inner surface 3i located at the tread portion 3t that contacts the road surface. In this specification, at least the width region TW in the tire axial direction in which the belt layer 7 is disposed. including. As a particularly preferable aspect, the sound control device 4 is attached so that the center of the width thereof is located on the tire equator C.

  The sound damper 10 has a substantially constant cross-sectional shape and extends in the tire circumferential direction. The “substantially constant cross-sectional shape” is used for the purpose of improving durability, and as shown in FIG. 2, tapered portions whose cross-sectional height gradually decreases are formed at both ends 10 e in the circumferential direction of the sound damper 10. It is because it has been. FIG. 2 shows a case in which a gap is formed between the end portions 10e and 10e of the sound damping body 10. However, by connecting the end portions 10e and 10e without any gap, The tool 4 may be formed in an annular shape. Further, as shown in FIG. 4 (A), the sound control device 4 may be spirally wound in the tire circumferential direction, and the sound control device 4 is divided into a plurality of pieces as shown in FIG. 4p may be intermittently arranged in the circumferential direction. Further, as shown in FIG. 4C, the sound control devices 4 may be arranged in a plurality of rows (for example, two rows).

  The sponge material forming the sound damping body 10 is a sponge-like porous structure. For example, in addition to a so-called sponge having open cells in which rubber or synthetic resin is foamed, animal fibers, plant fibers or synthetic fibers are used. Includes webs that are intertwined and connected together. The “porous structure” includes not only open cells but also closed cells. Preferably, a synthetic resin sponge such as an ether polyurethane sponge, an ester polyurethane sponge, or a polyethylene sponge, a rubber sponge such as a chloroprene rubber sponge (CR sponge), an ethylene propylene rubber sponge (EDPM sponge), or a nitrile rubber sponge (NBR sponge). Polyurethane sponges, particularly ether-based polyurethane sponges, are particularly preferred from the viewpoints of sound damping, light weight, foaming controllability, durability, and the like.

  If the specific gravity of the sponge material is too large, the tire weight is likely to increase. On the other hand, if the sponge material is too small, it is difficult to obtain sufficient strength and the effect of suppressing cavity resonance is reduced. From such a viewpoint, the lower limit of the specific gravity of the sponge material is preferably 0.005 or more, and more preferably 0.01 or more. The upper limit of the specific gravity is preferably 0.06 or less, more preferably 0.04 or less, and further preferably 0.03 or less.

  The volume Vs of the noise control body 10 is set to 0.4 to 20% of the total volume V of the tire lumen i. As described in Patent Document 1 described above, by securing 0.4% or more of the volume Vs of the noise control body 10 with respect to the total volume V of the tire lumen i, a remarkable 2 dB or more is obtained. Expected to reduce road noise. This noise reduction level can be said to be a value that can be clearly confirmed in the passenger compartment. From such a point of view, preferably, the volume Vs of the noise damper 10 is 1% or more, more preferably 2% or more, and more preferably 4% or more of the total volume V of the tire lumen i. On the other hand, if the volume Vs of the noise control body 10 exceeds 20% of the total volume V of the tire lumen i, the effect of reducing road noise will reach its peak, increase the cost, or deteriorate the weight balance of the assembly 1. It is easy to invite. From this point of view, the volume Vs of the sound damper 10 is particularly preferably 15% or less, more preferably 10% or less of the total volume V of the tire lumen i. In addition, such numerical limitation is not only in the case where the sound control device 4 is configured by one sound control body 10, but also in the case where it is formed by being divided into a plurality of or a plurality of sound control bodies 10, It has been confirmed that the same effect is exhibited if the total volume Vs is within the numerical range.

  Next, the cross-sectional shape and the like in the cross section in the width direction (the tire meridian cross section including the tire shaft) of the noise damper 10 are not particularly limited, but as shown in FIG. 6, the bottom surface 10A on the side bonded to the tread inner surface 3ti. And a maximum value tm of the thickness t between the upper surface 10B facing the tire lumen i and a width W1 of the bottom surface 10A larger than the maximum value tm of the bottom surface 10A. It is formed with a flat cross-sectional shape. The maximum value tm and the width W1 of the thickness are measured in a state (normal temperature and normal pressure) before the rim assembly with the noise control device 4 attached to the tire 3. The maximum value tm of the thickness is measured in a direction perpendicular to the bottom surface 10A, and the width W1 is measured along the bottom surface 10A.

  The inventors performed a tire removal test on an assembly in which a noise control body having a rectangular cross section is arranged on the inner surface 3ti of the tread. And the damage condition of the sound control body 10 was investigated. As shown in FIG. 5, the tire removal test was performed by a plurality of workers using a tire changer (not shown) and a tire lever f. The operator is not informed in advance of the presence of the sound control body. In addition, many types of sample assemblies were used, including various sound absorbers with different maximum thicknesses tm and tires with different flatness ratios.

  When the tire 3 is removed from the rim 2, the tire lever f is inserted into the tire lumen i. The insertion length is determined depending on the type of tire (category, flatness, etc.), operator technique, wrinkles during operation, etc. Varies depending on the situation. However, as a result of the test, it was found that the number of damages of the sound control body is reduced in the assembly having the sound control body in which the maximum thickness tm is limited to 5 to 45 mm. The reason for this is that the insertion length of the tire lever f is limited by the general knowledge of the operator who tries to prevent the contact between the tire lever f and the tire inner surface 3i, and therefore the sound damper with a small thickness t is used. On the other hand, contact opportunities are expected to decrease. However, when the flat tire has a flatness ratio of 50% or less, the tire lever f tends to come into contact with the side surface of the sound control body more frequently.

Therefore, when further experiments were repeated, as shown in FIG. 5, in the tire meridian section,
(1) A peak 20t where the thickness t has a maximum value tm, a valley bottom 21b which is located on both sides of the peak 20t and has a minimum value ti, and each valley bottom from the peak 20t The upper surface 10B of the sound damper 10 extends along a wavy curve 24 in which the wave element 23 composed of the inclined portion 22 extending 21b is repeated in the width direction:
(2) The width direction both ends 10Be of the upper surface 10B terminate at the valley bottom portion 21b or the inclined portion 22; and (3) The thickness te from the bottom surface 10A of the width direction both ends 10Be of the upper surface 10B is Be in the range of 1.0 to 15.0 mm;
Thus, it has been found that the tire lever f can be prevented from being damaged.

  In other words, when the upper surface 10B extends along the wavy curve 24, the sound damping body 10 has alternating peaks 20 having a large thickness and valleys 21 having a small thickness. It is formed. In addition, both end portions of the sound damper 10 are terminated at the trough portion 21, and the thickness te of the both end portions from the bottom surface 10 </ b> A is restricted to a range of 1.0 to 15.0 mm. The peak portion 20 is defined by a portion having a thickness larger than the amplitude center line KL with respect to the amplitude center line KL of the wavy curve 24, and the valley portion 21 is defined by the amplitude center line KL. The thickness t is defined by a smaller portion.

  1, 3, 6, and 8 show a case where the wavy curve 24 has a trapezoidal wave shape as a first embodiment of the sound damper 10. In the first embodiment, as shown in FIG. 6, the wavy curve 24 has the peak 20t formed of a linear upper side 30 parallel to the bottom surface 10A and the valley bottom 21b parallel to the bottom 10A. The trapezoidal wave-like curve is formed by repeating the wave element 23 composed of the linear lower side 31 and the inclined portion 22 composed of the linear hypotenuse 32 in the width direction. The hypotenuse 32 can be provided with an arc portion having a radius of curvature that is sufficiently smaller than the entire length of the hypotenuse 32 at the connection with the upper side 30 and / or the lower side 31. Here, the radius of curvature sufficiently smaller than the entire length of the hypotenuse 32 means 42% or less of the total length of the hypotenuse 32, preferably 35% or less, more preferably 20% or less.

  As described above, both ends of the sound damper 10 are terminated at the valley 21 and the thickness te of both ends is regulated to 15.0 mm or less. Therefore, contact between the tire lever f and the sound control body 10 is further avoided. Moreover, the sound damper 10 is composed of gentle inclined portions 22 from both end portions thereof to the peak portion 20t. By such an inclined portion 22, as shown in FIG. 7, a portion that easily interferes with the tire lever f is removed. Accordingly, contact between the tire lever f and the sound control body 10 is further avoided. The inclined portion 22 approximates an arcuate locus fL drawn by the tip of the tire lever f. Therefore, even if the tire lever f comes into contact with the sound damping body 10, the frictional force between the tire lever f and the inclined portion 22 is small, and the tip of the tire lever f does not easily bite into the sound damping body 10. And by these interaction, the remarkable damage of the damping body 10 and peeling from the tire 3 of the damping body 10 can be prevented effectively.

  If the thickness te of the both ends exceeds 15.0 mm, both ends of the sound damper 10 are likely to interfere with the tire lever f. Therefore, the thickness te is preferably 15.0 mm or less, more preferably 10.0 mm or less, and even 7.0 mm or less from the viewpoint of preventing damage to the sound damper 10. However, when the thickness te is smaller than 1.0 mm, it is difficult to obtain an effect of improving the productivity of the sound damper 10, and therefore the thickness te is 1.0 mm or more, further 3.0 mm or more, 4.0 mm or more is preferable. Further, the minimum thickness ti is preferably 1.0 mm or more, more preferably 3.0 mm or more, and further preferably 4.0 mm or more from the viewpoint of improving productivity. In particular, the thickness te of the both end portions is equal to the minimum value ti of the thickness, that is, the end portions of the sound damping body 10 are terminated at the valley bottom 21b to prevent damage to the sound damping body 10. From the viewpoint of improving productivity. However, if the thickness is within the range, the thickness te is larger than the minimum value ti, that is, both end portions or one end portion of the sound damper 10 are terminated on the inclined portion 22 different from the valley bottom portion 21b. You may do it.

  In addition, in the wavy curve 24 that determines the contour shape of the upper surface 10B, if the amplitude H is too small, the surface area of the upper surface 10B becomes small and the resonance suppression effect in the tire lumen i tends to decrease, and conversely it is too large. However, the inclined portion 22 becomes steep, which is disadvantageous for preventing damage to the sound damper 10. From such a viewpoint, the lower limit value of the amplitude H is preferably 4 mm or more, more preferably 8 mm or more, and more preferably 10 mm or more, and the upper limit value is 44 mm or less, further 40 mm or less, further 35 mm or less, and further 30 mm. The following is preferred.

  1, 3, and 6, the number of peaks 20 t formed on the top surface 10 </ b> B of the sound damping body 10 is one, particularly the top surface 10 </ b> B is formed by one wave element 23, that is, the sound damping body 10. A case is shown in which both ends of each end at the valley bottom 20b. However, the number of peak portions 20t formed on the upper surface 10B may be two or more, and FIG. 8 shows an embodiment in which the number of formations, particularly, the upper surface 10B is formed by two wave elements 23.

  When the number of the peak portions 20t is 2 or more, when the tire lever f is in contact with the inclined portion 22 by the valley portion 21 formed between the peak portions 20, the inward width direction of the peak portion 20 is reached. Deformation is easy. Therefore, the sound control body 10 can be released from the tire lever f, and the biting of the tire lever f can be further suppressed. In addition, the valley portion 21 is useful for preventing damage to the sound control body 10 and the tire 3 due to heat in order to suppress heat storage of the sound control body 10.

  If the width W1 of the bottom surface 10A is too large, the workability of attaching to the tire inner surface 3i tends to be lowered. From such a viewpoint, the width W1 of the bottom surface 10A is preferably 100% or less, more preferably 70% or less of the tread width TW.

  Further, as shown in FIG. 9, as the sound damping body 10, the wavy curve 24 may be a sine wave shape, and the same effect as in the first embodiment of the trapezoidal wave shape can be obtained. In such a case, in order to approximate the inclined portion 22 by the locus fL of the tire lever f, a ratio H / Wp between the wave pitch Wp, which is the width of the wave element 23, and the amplitude H is set to 0.3. In the following, it is more preferable to set it to 0.25 or less.

  Next, the protective layer 11 (shown in FIG. 3) is made of a thin resin film 12 having a light shielding property with a thickness of about 0.01 to 0.10 mm, for example. It is formed by adhering to the surface.

  As the adhesive, an isocyanate compound alone or an isocyanate-terminated prepolymer bonded with a polyol can be suitably used. These are also raw materials for polyurethane sponge, and can firmly adhere to a sponge material, particularly an ether polyurethane sponge material. The isocyanate compound is not particularly limited as long as it produces a urethane prepolymer. For example, aromatic polyisocyanate, aliphatic polyisocyanate, alicyclic polyisocyanate, carbodiimide-modified polyisocyanate of the above polyisocyanate, or these Examples include isocyanurate-modified polyisocyanate. And these are used individually by 1 type or in combination of 2 or more types.

Specific examples of the aromatic-containing polyisocyanate include 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), and 4,4′-diphenylmethane diisocyanate. (4,4′-MDI), 2,4′-diphenylmethane diison anate (2,4′-MDI),
Examples include p-phenylene diisocyanate, polymethylene polyphenylene polyisocyanate, xylylene diisocyanate (XDI), tetramethylxylylene diisocyanate (TMXDI), 1,5-naphthalene diisocyanate (NDI), and tolidine diisocyanate (TODI).
Specific examples of the aliphatic polyisocyanate include hexamethylene diisocyanate (HDI).
Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate, H6 XDI (hydrogenated XDI), and H12 MDI (hydrogenated MDI).

  In the case of an isocyanate-terminated prepolymer (prepolymer adsorbent), the molar ratio (NCO / OH) of the isocyanate group (NCO) in the polyisocyanate compound to the hydroxyl group (OH) of the polyol as a raw material is 1.5-2. The range is .5. When the molar ratio (NCO / OH) is less than 1.5, the viscosity of the resulting urethane prepolymer becomes too high to be used for a moisture-curable adhesive. On the other hand, when the molar ratio (NCO / HO) exceeds 2.5, foaming is likely to occur during curing, and the cohesive strength of the cured product is reduced, and sufficient adhesive strength cannot be obtained.

  As the resin film 12, various resin films such as polyvinyl chloride (PVC), acrylonitrile / styrene (AN / ST), polyethylene terephthalate (PET), polyethylene (PE), etc. can be used as long as they have light shielding properties. The material can be used. However, in order to obtain an excellent evaluation in the running durability test, it is necessary that the resin film 12 and the sound damping body 10 (sponge material) be firmly bonded. For this purpose, a polyurethane resin film is used. I like this.

  Here, having light-shielding properties means performance capable of shielding ultraviolet rays and suppressing the transmittance to 20% or less. This light-shielding property can be imparted, for example, by adding a light-shielding agent made of an ultraviolet absorber, an ultraviolet diffusing agent, a coloring dye, or the like to the resin material of the resin film 12. Alternatively, the surface of the resin film 12 can be imparted by performing a light shielding treatment such as coating a film containing the light shielding agent such as vapor deposition of metal (aluminum) or the like.

  Such a resin film 12 covers and protects a part of the surface of the sound damping body 10, thereby preventing the sound damping body 10 from being deteriorated by ultraviolet rays and preventing the strength of the sound damping body 10 from being lowered during storage. . From the viewpoint of preventing this deterioration, the protective layer 11 covers the entire circumference of the cross-section in the width direction in an airtight manner over a length range of 70% or more, further 90% or more of the entire length of the sound damper 10. Is preferred. However, if the sound damper 10 is completely sealed, the sound absorber 10 may excessively rise in temperature during traveling. Further, both end portions in the circumferential direction of the sound damper 10 are less likely to be deteriorated such that ultraviolet rays do not act directly. Therefore, in this example, the protective layer 11 is not formed only at both ends in the circumferential direction of the sound damping body 10, thereby ensuring the air permeability of the sound damping body 10. In the case of this example, at the time of storing the tire, by holding the tire 3 upright with both ends in the circumferential direction facing upward, it is possible to prevent water absorption such as rain water and condensed water from both ends in the circumferential direction. Therefore, it is possible to prevent adverse effects such as unbalanced tire weight. However, the protective layer 11 may be formed on both ends of the sound damper 10 in the circumferential direction so that the sound damper 10 is completely sealed.

Moreover, the following protective layer formation method I is employable by use of the said adhesive agent. In this forming method I, as shown in FIG. 10A, the adhesive is applied to the bottom surface 10A and the top surface 10B of the sound damper 10 using a known roll coater (not shown). The coating amount at this time is about 24 g per 1 m ² . Next, as shown in FIGS. 10B to 10C, the sound control body 10 is placed on the resin film 12 that has been cut into a predetermined size in advance with the bottom surface 10A facing downward. Thereafter, the width direction both side portions 12e of the resin film 12 are folded back, and the respective side portions 12e are overlapped and covered with the upper surface 10B of the sound control body 10. The protruding portion of the resin film 12 that protrudes from both ends in the circumferential direction of the sound damping body 10 is usually excised, but it may be folded back to cover both ends in the circumferential direction of the sound damping body 10. After that, for example, by using a heating press machine or the like to cure the adhesive, the sound control device 4 in which the entire circumference of the cross section in the width direction of the sound control body 10 is covered and protected by the protective layer 11 is efficiently obtained. Can be formed. In this forming method, as in this example, the wavy curve 24 of the upper surface 10B is preferably trapezoidal from the viewpoint of securing the bonding area on the upper surface 10B.

  In addition to the protective layer forming method I using the adhesive, for example, as schematically shown in FIG. 11, a method of covering the sound damping body 10 so as to be wrapped with the resin film 12, that is, around the sound damping body 10. A method II may be considered in which the protective film is formed by tightly winding the resin film 12 and closing the joint J (seam portion) surface with an adhesive tape 15 such as vinyl. However, such a packaging method II is difficult to mechanize such as having a skill level because the sound control body 10 is soft and long, and it takes about 40 minutes to form one sound control tool. That is, the productivity is inferior to that of the forming method I, such as requiring about 8 times the work time. Further, the reliability for sealing the mating portion J is also poor.

  The sound control device 4 configured as described above can be fixed to the tire inner surface 3i by various methods, but it is particularly preferable to adhere the double-sided adhesive tape from the viewpoint of cost and workability. And the sound control tool 4 is adhere | attached on the pneumatic tire 3, and these can also be set sale etc. as a composite_body | complex of the pneumatic tire 3 and the sound control tool 4. FIG. In order to improve adhesiveness, it is desirable that the tire inner surface 3i be finished smooth. Usually, the tire inner surface 3i is formed with a ridge formed by transferring an exhaust groove formed on the surface of the vulcanization bladder, but it is desirable to remove and smooth the ridge. Also, by using a bladder with no exhaust groove on the surface, the tire inner surface can be finished flat from the beginning. In order to further improve the adhesion to the tire inner surface 3i, the tire is preferably vulcanized without applying a release agent to the tire inner surface 3i.

  In the sound control device 4 as described above, since the protective layer 11 made of the resin film 12 is thin and can transmit sound vibration, vibration waves of air generated in the tire lumen i cause the protective layer 11 to pass through. It passes and is transmitted to the sound control body 10 (sponge material). As a result, part of the vibration energy of the cavity resonance is consumed as thermal energy, and road noise can be reduced. Further, since the resin film 12 is thin, the flexibility of the sound control body 10 can be maintained to some extent, and therefore the rim assembly property is not deteriorated and steering stability is not affected. In the forming method of this example, the resin film 12 is not in close contact with the entire surface of the sound damper 10, and therefore, when the tire 3 is removed from the rim 2, the tire lever f and the resin film 12 come into contact with each other. There is a fear. However, since the resin film 12 is thin and easily deformed, it can easily escape from the tire lever f at the time of contact, and the frictional force with the tire lever f is also small. Therefore, the above-described effect due to the upper surface 10B of the sound damper 10 having a wavy curve can also be exhibited.

  Although the embodiment of the present invention has been described above, the above embodiment is merely an example, and it is needless to say that the present invention can be modified and implemented in various modes.

  A sound damper having the specifications shown in Table 1 is bonded to the inner surface of a tread of a radial tire for a passenger car (215 / 45R17) to produce a composite of the tire and the noise suppressor. The noise performance was tested.

The sound control device uses an ether polyurethane sponge with a specific gravity of 0.016 (product number E16, Maruzu). Both ends in the tire circumferential direction are tapered at 45 ° as shown in FIG. gave. In each example, the total volume V of the tire lumen, the volume Vs of the sound damper and the cross-sectional shape (shown in FIG. 12) are all the same, and the total volume V of the tire lumen is 25318 cm ³ . The volume Vs is 2300 cm ³ and the ratio Vs / V is 9.1% (note that the unit in FIG. 12 is mm). Further, the sound control tool and the inner surface of the tread were bonded using a double-sided adhesive tape (manufactured by Nitto Denko Corporation, model 5000NS). The tire was vulcanized without applying a release agent to the inner surface of the tire, and a bladder without an exhaust groove on the surface was used as a bladder for forming the inner surface of the tire. For this reason, the inner surface of the tire is finished flat, and good adhesion to the sound control tool is obtained.

  In addition, as a resin film for the protective layer in the table, film A is a polyethylene food packaging wrap film manufactured by ITOCHU Sampras Co., Ltd., film B is a polyethylene film manufactured by Mitomo Sangyo Co., Ltd., and film C is Okura Kogyo Co., Ltd. Polyurethane film made from was used.

  In addition, the sound-damping tool before bonding is cut at a length of 150 mm, and a sound-damping tool sample without a protective layer is prepared on both ends in the length direction, and the anti-exposure performance test is performed on the sound-damping tool sample. Went.

  In Comparative Examples 1 and 2, the protective layer is formed by the packaging method II using a commercially available adhesive tape without using an adhesive. In the examples, the protective layer is formed by the forming method I using an adhesive (isocyanate compound). The formation efficiency of the protective layer is indicated by the time (minutes) required for one worker to form the protective layer on one sound absorber.

(1) Water absorption performance:
In a state where the composite is erected (both ends in the circumferential direction of the sound control device are on the upper side), 3 liters of water is poured and left for 24 hours. Thereafter, water was discarded, and water on the tire inner surface and the surface of the noise control body was removed with a cloth, and the increased weight was measured. Even when there is no sound control, the inner surface of the tire is not completely dry, so that the weight is usually increased by 10 g.
The composite immediately after the water absorption test was mounted on the right front wheel of the vehicle (2000 cc domestic FR vehicle) with internal pressure (200 kPa) and rim (17 × 7JJ), and the peripheral circuit was run at a speed of 100 km / h. The presence or absence of vibration was evaluated based on the driver's sensation.

(2) Noise performance:
A dry composite that is not used for water absorption performance is mounted on all wheels of a vehicle (2000cc domestic FR vehicle) with internal pressure (200kPa) and rim (17x7JJ), and road noise with one passenger Car interior noise when driving at a speed of 60 km / h on the measurement road (asphalt rough road) is measured at the driver's window side ear position, and the sound pressure level of the peak value of air column resonance around 240 Hz is compared. The increase / decrease value based on Example 1 is shown. -(Minus) display means a reduction in road noise.

(3) Exposure resistance:
Using a sunshine carbon arc lamp type light resistance and weather resistance tester stipulated in JIS B7753, artificial light irradiation (90 minutes) and water spray (10 minutes) approximate to sunlight at a temperature of 63 ° C The cycle was repeated. And the powdered part which sponge material deteriorated was shaken off from the edge part of the noise suppression tool sample, and while the weight reduction amount of the noise suppression body by this was measured, the result was shown in FIG. The smaller the weight loss, the better the exposure resistance. In addition, although the sponge material is exposed at both ends of the sound damping sample, water and light do not act directly, and deterioration can be almost ignored.

  As shown in the table, in the examples, it can be confirmed that the deterioration due to the exposure of the sound damper can be effectively prevented while the road noise reduction effect is sufficiently exhibited, and the durability of the sound damper can be maintained.

It is sectional drawing which shows the assembly of the pneumatic tire and rim | limb of this invention. It is the II end view. It is an expanded sectional view showing the composite of a tire and a sound control body. (A)-(C) are the perspective views which show schematically the other example of the formation state of a damping body. It is sectional drawing explaining the operation | work which removes a tire from a rim | limb using a tire lever. It is an enlarged view of a sound control body. It is a fragmentary sectional view explaining the positional relationship between a sound control body and a tire lever. It is sectional drawing which shows the other example of a damping body. It is sectional drawing which shows the other example of a noise suppression body. (A)-(C) are sectional drawings which show the protective layer formation method to a noise suppression body. It is a perspective view which shows the protective layer formation method to the noise suppression body using an adhesive tape. It is sectional drawing which shows the cross-sectional shape and dimension of a noise suppression body used for Table 1. FIG. It is a graph which shows the result of an exposure resistance test. It is a fragmentary sectional view of the tire assembly which shows an example of the conventional noise suppression tool.

Explanation of symbols

2 Rim 3 Pneumatic tire 3ti Tread inner surface 4 Damping tool 10 Damping body 10e Both ends 10A in the circumferential direction Bottom surface 10B Upper surface 11 Protective layer 12 Resin film 20 Mountain peak portion 21 Valley bottom portion 22 Inclined portion 23 Wave element 24 Wavy curve i In tire Cavity

Claims (6)

A rim, a pneumatic tire attached to the rim, and a band-shaped sound damping tool fixed in a tire lumen surrounded by the rim and the pneumatic tire and extending in the tire circumferential direction,
The sound control device is composed of a sound control body made of a sponge material having a volume of 0.4 to 20% of the total volume of the tire lumen, and a light- shielding resin film having an ultraviolet transmittance of 20% or less and bonded. A protective layer covering the surface by being adhered to the surface of the sound control body via an agent ;
The pneumatic tire and rim assembly , wherein the adhesive is made of an isocyanate compound, and the resin film is made of a polyurethane resin . 2. The pneumatic tire and rim assembly according to claim 1 , wherein the sound control tool does not include the protective layer at both ends in the circumferential direction of the sound control body. A rim, a pneumatic tire attached to the rim, and a band-shaped sound damping tool fixed in a tire lumen surrounded by the rim and the pneumatic tire and extending in the tire circumferential direction,
The sound control device is composed of a sound control body made of a sponge material having a volume of 0.4 to 20% of the total volume of the tire lumen, and a light-shielding resin film having an ultraviolet transmittance of 20% or less and bonded. A protective layer covering the surface by being adhered to the surface of the sound control body via an agent;
The sound control tool is fixed to the inner surface of the tread, and the sound control body has a bottom surface on the inner surface side of the tread and an upper surface facing the tire lumen,
In the tire meridian cross section including the tire axis, the sound damping body has a maximum thickness (tm) from the bottom surface to the top surface in the range of 5 to 45 mm, and the bottom surface width (W1) is the maximum thickness. A laterally oblong cross-sectional shape larger than the value (tm), and the upper surface has a peak having the maximum value (tm) of the thickness, and is located on both sides of the peak and has a minimum thickness ( ti) and a wave element composed of a sloped part extending from the peak to the bottom of each valley along a wave-like curve repeated in the width direction, and both ends in the width direction of the upper surface are the valley bottom or with terminating at inclined portions, the thickness from the bottom surface of the width direction ends of the upper surface (te) is provided with air-filled tires and rims you characterized in that the range of 1.0~15.0mm Assembly. 4. The pneumatic tire and rim assembly according to claim 3 , wherein the sound control tool does not include the protective layer at both ends in the circumferential direction of the sound control body. The pneumatic tire and rim assembly according to claim 3 or 4, wherein the adhesive is made of an isocyanate compound, and the resin film is made of a polyurethane resin . A composite of a pneumatic tire and a sound control body, comprising the pneumatic tire and the sound control tool described in any one of claims 1 to 5 fixed to the inner surface of the tread of the pneumatic tire.

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