JP2006143021A - Assembly of pneumatic tire and rim - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an assembly of a pneumatic tire and a rim capable of preventing damage to a band-like body comprising a sponge material arranged at the inside of the tire at tire exchange or the like. <P>SOLUTION: In the assembly 1 of the pneumatic tire and the rim, the band-like body 4 comprising the sponge material extending in a tire circumferential direction and having a volume of 0.4-20(%) of the whole volume of the inside of the tire is arranged at the inside i of the tire surrounded by the rim 2 and the pneumatic tire 3. The band-like body 4 is made to a laterally lengthy flat shape so that a maximum thickness from a fixed surface fixed to a tire inner side surface 3i or a rim inner side surface 2i to a free surface facing the inside of the tire is 5-45 mm, and the width of the fixed surface is larger than the thickness and includes at least one crest 10; taper parts 12 provided at both side of the crest 10 and having a gradually reduced thickness; and at least one valley 11 continued to the taper part 12 and extending in a width direction at a minimum thickness. Thereby, the free surface 4B of the band-like body 4 forms a trapezoid wave shape. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an assembly of a pneumatic tire and a rim in which a belt-like body made of a sponge material is disposed in a tire lumen.

  Road noise is known as one of tire noises generated when a vehicle travels on a road surface. Road noise is a sound having a frequency of about 50 to 400 Hz, and is heard by a passenger as a “go” sound. One of the main causes of road noise is air resonance vibration (cavity resonance) generated in the tire lumen. In order to reduce such road noise, the applicant of the present application, for example, as shown in FIG. 14, a tire and a rim in which a belt-like body b made of a sponge material extending in the tire circumferential direction is arranged in the tire lumen a. Has already been proposed (see, for example, Patent Document 1 below). The strip 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 2003-252003 A

  By the way, when removing the pneumatic tire d from the rim e, the air filled in the tire lumen a is first evacuated, and a part of the bead portion d1 of the tire d is dropped into the well portion e2 of the rim. Thereafter, the tire lever f is inserted into the gap between the bead portion d1 and the flange e1 of the rim e, and is tilted with the outer edge of the flange e1 of the rim as a fulcrum, thereby moving the bead portion d1 to the outside of the flange e1. Pulling out is done.

  However, the conventional belt-like body b has a relatively large thickness, and its cross-sectional shape is a rectangular shape or a vertically long trapezoidal shape, and both side surfaces rise with a relatively steep slope. For this reason, as shown by the phantom line in FIG. 14, the tip of the tire lever f comes into contact with the band-shaped body b, and the band-shaped body b is damaged or the band-shaped body is peeled off from the tire d. was there.

  The present invention has been devised in view of the above circumstances, and in a meridian cross section including a tire rotation axis, the band-like body is a horizontally long flat shape with a maximum thickness limited, and the band-like body is a maximum. At least one peak portion extending in the width direction at a thickness of, a taper portion provided on both sides of the peak portion and gradually decreasing in thickness, and at least one extending in the width direction at a minimum thickness connected to the taper portion. By including two troughs, the free surface of the strip is made trapezoidal and the both ends of the strip are provided with the trough or the taper having a thickness of 1.0 to 15.0 mm. Based on the above, it is intended to provide a pneumatic tire and rim assembly that can reduce the chance of contact between the belt-like body and the tire lever and prevent the damage, particularly when removing the tire from the rim, such as when exchanging the tire. It is aimed.

  The invention according to claim 1 of the present invention has a rim, a pneumatic tire attached to the rim, and a tire lumen that surrounds the rim and the pneumatic tire, and has a volume extending in the tire circumferential direction. An assembly of a pneumatic tire and a rim on which a band-shaped body made of a sponge material, which is 0.4 to 20% of the total volume of the tire lumen, is disposed, and the band-shaped body has a tire rotation axis. In the meridian cross section, the maximum thickness from the fixed surface fixed to the inner surface of the tire or the inner surface of the rim to the free surface facing the tire lumen is 5 to 45 (mm) and the fixed surface is larger than this thickness. The belt-shaped body has a horizontally long flat shape having a large width, and at least one peak portion extending in the width direction with the maximum thickness, and a tapered portion that is provided on both sides of the peak portion and gradually decreases in thickness. Consecutive to this taper, and with minimum thickness and width And the free surface of the band-like body has a trapezoidal wave shape, and both ends of the band-like body have a thickness of 1.0 to 15.0 mm or the taper. It consists of parts.

  The invention according to claim 2 is the pneumatic tire and rim set according to claim 1, characterized in that the belt-like body has valleys at both ends and has one peak between them. It is a solid.

  The invention according to claim 3 is the pneumatic tire and rim assembly according to claim 2, wherein the sum of the widths of the valleys is greater than 0 mm and less than or equal to the width of the peaks. It is.

  According to a fourth aspect of the present invention, in the belt-like body, the sum of the widths of the valleys is substantially equal to the width of the peak parts. It is a solid.

  The invention according to claim 5 is characterized in that the belt-like body has two peak portions and includes a valley portion between the two peak portions. It is an assembly.

  The invention according to claim 6 is the pneumatic tire and rim assembly according to claim 5, wherein the belt-like body has tapered portions at both ends.

  The invention according to claim 7 is a pneumatic tire comprising a pneumatic tire and a belt-like body according to any one of claims 1 to 4 fixed to the inner surface of the tread of the pneumatic tire. It is a complex.

  The invention according to claim 8 is the belt-like body according to any one of claims 1 to 6, wherein a flat sponge material having a substantially constant thickness is perpendicular to the thickness direction. A contour processing step of continuously slicing along a first trapezoidal wave-shaped cut surface along the first direction to obtain two slice materials in which one surface has a flat shape and the other surface has a trapezoidal wave shape; The slicing material is formed through a dividing step of dividing the sliced material along a second direction perpendicular to the first direction and the thickness direction at a valley portion forming the minimum thickness. It is said.

Here, the volume of the belt-like body is an apparent volume determined from the outer shape of the belt-like body, 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 the formula (1), “A” is a tire lumen area obtained by CT scanning of the tire lumen in the normal state, “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. “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 is for JATMA, and the table is “TIRE LOAD LIMITS AT” for TRA. Maximum value described in “VARIOUS COLD INFLATION PRESSURES”, “INFLATION PRESSURE” if it is ETRTO, but if tires are for passenger cars, it will be uniformly 200 kPa considering the actual frequency of use.

  The belt-like body used in the present invention has a horizontally long flat shape in which the maximum thickness from the fixed surface fixed to the tire inner surface or the rim inner surface to the free surface facing the tire lumen is limited to 5 to 45 mm. . For this reason, the protruding height of the belt-like body from the tire inner surface or the rim inner surface can be reduced. This helps to reduce the chance of contact with the tire lever inserted into the tire lumen during tire replacement.

  The band-shaped body has at least one peak portion extending in the width direction with the maximum thickness, a taper portion provided on both sides of the peak portion and gradually decreasing in thickness, and connected to the taper portion with a minimum thickness. By including at least one trough extending in the width direction, the free surface has a trapezoidal wave shape, and a trough or a taper having a limited thickness is provided at both ends of the belt-like body. Since the tire lever is particularly easy to contact with both ends of the belt-like body, the contact between the tire lever and the belt-like body can be further prevented by positioning a valley or taper portion having a small thickness at both ends of the belt-like body. .

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a tire rotation axis of a pneumatic tire (hereinafter simply referred to as “tire”) and a rim assembly (hereinafter also simply referred to as “assembly”) 1 of the present embodiment. FIG. 2 shows an AA end view, and FIG. 3 shows an enlarged sectional view showing the tire in an enlarged manner.

  The assembly 1 of the present embodiment includes a rim 2, a tire 3 attached to the rim 2, and a belt-like body 4 disposed in a tire lumen i surrounded by the rim 2 and the tire 3. Composed.

  In the present embodiment, the rim 2 is a so-called metal two-piece wheel rim having a rim body 2a to which the bead portion 3b of the tire 3 is mounted and a disk 2b that holds the rim body 2a and is fixed to the axle. Illustrated. However, it is not limited to this, and it is needless to say that 1 pcs rim may be used.

  As shown in FIG. 3, the tire 3 includes a tread portion 3t, a pair of sidewall portions 3s extending inward in the tire radial direction from both ends thereof, and a pair of bead portions provided at the inner ends thereof. 3b. The tire 3 is exemplified by a tubeless type radial tire for a passenger car reinforced by at least a radial carcass 6 and a belt layer 7 disposed outside the tire radial direction and inside the tread portion 3t. The tire 3 of the present embodiment is an ultra-low flat radial tire having a flatness ratio of 50% or less, and is formed with a small tire cross-sectional height. The internal structure and category of the tire 3 are not particularly limited, but a passenger car tire that is strongly required to be quiet in the passenger compartment is desirable.

  The carcass 6 is composed of, for example, one or a plurality of carcass plies 6A using an organic fiber cord, in this example, one carcass ply 6A, and both end portions thereof are folded around the bead core 8. The belt layer 7 is composed of two outer belt plies 7A and 7B, which are stacked in the tire radial direction in this example. Each belt ply 7A, 7B is arranged with the steel cord inclined with respect to the tire equator C at an angle of about 10 to 40 °, for example, and is overlapped in a direction in which the steel cords cross each other. Note that a known band layer or the like may be provided outside the belt layer 7 as necessary.

  The belt-like body 4 has a belt-like shape that is long in the tire circumferential direction, and extends in the tire circumferential direction with substantially the same cross-sectional shape in this embodiment. As shown in FIG. 2, “substantially” means that each end 4 e, 4 e in the circumferential direction of the strip 4 has a tapered portion whose sectional shape gradually decreases for the purpose of improving durability. This is because there is provided. For example, the belt-like body 4 is formed into a rod shape, and then curved in a circular arc shape in the tire circumferential direction along the tire lumen surface 3i, and is fixed to the tire inner surface 3i using a double-sided adhesive tape, an adhesive, or the like. . In the example of FIG. 2, the end portions 4e and 4e of the belt-like body 4 are separated by a slight gap, but may be joined so as to continue 360 °. Although not shown in the figure, the belt-like body 4 may be fixed to the tire inner side surface 3i or the like in a spiral manner continuously in the tire circumferential direction. Furthermore, the belt-like body 4 may be divided into two or more and may be arranged intermittently in the tire circumferential direction and / or in parallel in the tire axial direction.

  The strip 4 is made of a sponge material. The sponge material is a sponge-like porous structure, for example, a web in which animal fibers, plant fibers, or synthetic fibers are entangled and integrally connected in addition to a so-called sponge having open cells in which rubber or synthetic resin is foamed. It shall be included. The “porous structure” includes not only open cells but also those having closed cells.

  The sponge material as described above converts vibration energy of air that vibrates on the surface or inside of the porous portion into heat energy. As a result, cavity resonance in the tire lumen i is suppressed, and road noise is reduced. Further, since the sponge material is easily deformed such as contraction and bending, it does not substantially affect the deformation of the tire during running. For this reason, it can prevent that steering stability deteriorates.

  The sponge material is preferably an ether polyurethane sponge, ester polyurethane sponge, synthetic resin sponge such as polyethylene sponge, chloroprene rubber sponge (CR sponge), ethylene propylene rubber sponge (EDPM sponge), nitrile rubber sponge (NBR sponge), etc. A rubber sponge can be suitably used, and a polyurethane or polyethylene-based sponge including an ether polyurethane sponge is particularly preferable from the viewpoints of sound damping properties, light weight, foaming controllability, durability, and the like.

The specific gravity of the sponge material is not particularly limited, but if it is too large, the tire weight tends to increase, and conversely if it is too small, the effect of suppressing cavity resonance tends to decrease. From such a viewpoint, the specific gravity of the sponge material is preferably 0.005 or more, more preferably 0.01 or more, and the upper limit is preferably 0.06 or less, more preferably 0.04 or less, and still more preferably. 0.03 or less is desirable (in terms of density, preferably 5 kg / m ³ or more, more preferably 10 kg / m ³ or more, and the upper limit is preferably 60 kg / m ³ or less, more preferably 40 kg / m ³ or less. More preferably, it is 30 kg / m ³ or less.)

  The strip 4 has a volume Vs of 0.4 to 20% of the total volume V of the tire lumen. FIG. 4 shows a result of an experiment when the road noise is measured by disposing the band 4 in the tire lumen i. The vertical axis represents the road noise reduction allowance, and the horizontal axis represents the volume ratio (Vs / V). The road noise reduction allowance is a road noise reduction amount (dB) when compared with an assembly in which no belt-like body is arranged in the tire lumen i.

  As is clear from FIG. 4, a road noise reduction effect of approximately 2 dB or more can be expected by securing the volume of the strip 4 to 0.4% or more with respect to the total volume of the tire lumen i. This noise reduction level can be said to be a value that can be clearly confirmed in the passenger compartment. Particularly preferably, the strip 4 has a volume Vs of 1% or more, more preferably 2% or more, more preferably 4% or more of the total volume of the tire lumen i. On the other hand, when the volume of the belt-like body 4 exceeds 20% of the total volume of the tire lumen i, the effect of reducing the road noise becomes a peak and the cost is easily increased or the weight balance of the assembly 1 is easily deteriorated. From such a viewpoint, the volume of the belt-like body 4 is preferably 16% or less, more preferably 10% or less of the total volume of the tire lumen i. Although this experimental result uses one strip 4, even if the strip 4 is divided into two, the same effect is exhibited as long as the total volume is within the above numerical range. It has been confirmed that

  The belt-like body 4 has a fixed surface 4A fixed to the tire inner side surface 3i or the rim inner side surface 2i, and a free surface 4B located on the opposite side of the fixed surface 4A and facing the tire lumen i. The fixed surface 4A prevents the strip 4 from freely moving in the tire lumen i during traveling, prevents damage to the strip 4 and provides a stable resonance suppression effect. Note that the fixed surface 4A of the present embodiment is formed of a substantially smooth flat surface.

  The tire inner surface 3i is the surface of the tire 3 facing the tire lumen i, and the rim inner surface 2i is the surface of the rim 2 facing the tire lumen i. Since the rim inner side surface 2i may be strongly pressed by the bead portion 3b during tire replacement, the belt-like body 4 is preferably fixed to the tire inner side surface 3i, particularly the tread inner side surface 3ti, as in the present embodiment. Is desirable.

  The tread inner side surface 3ti means the inner side of the tread surface that contacts the road surface of the tire inner side surface 3i, and includes at least a range in the tire axial direction in which the belt layer 7 is disposed in the present specification. As a particularly preferred embodiment, as shown in FIG. 3, the center of the width W1 of the fixing surface 4A of the strip 4 is substantially aligned with the center of the tread inner surface 3ti in the tire axial direction (that is, the tire equator C). It is desirable to be fixed. More preferably, the strip 4 has a symmetrical arrangement and cross-sectional shape around the tire equator C as in the present embodiment.

  Further, as shown in FIG. 5, the strip 4 has a maximum thickness tm from the fixed surface 4A to the free surface 4B of 5 to 45 mm in the meridian cross section including the tire rotation axis, and from this thickness tm Also, the fixed surface 4A is formed in a horizontally flat shape having a large width W1. The thickness tm and the width W1 are measured in a state in which the strip 4 is attached to the tire 3 and before the rim assembly (normal temperature and normal pressure), and the thickness tm is perpendicular to the fixed surface 4A. The width W1 is measured along the fixed surface 4A.

  The inventors performed a tire removal test on the assembly 1 in which the belt-like body 4 having a rectangular cross section is disposed on the inner surface 3ti of the tread. And the damage condition of the strip | belt-shaped body 4 was investigated. As illustrated in FIG. 14, the tire removal test was performed by a plurality of workers using a tire changer and a tire lever f (not shown). The operator is not informed in advance of the presence of the strip. In addition, many types of sample assemblies were used, such as various strips having different maximum thicknesses tm and tires having 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 testing, it has been found that the number of breakage of the belt-like body is reduced in the assembly having the belt-like body 4 in which the maximum thickness tm is limited to 5 to 45 mm. The reason for this is that there is an almost constant upper limit for the insertion length of the tire lever f due to the general knowledge of the worker who tries to prevent the contact between the tire lever and the tire inner surface 3i. It is considered that the chance of contact with the small band 4 is reduced. However, the inventors considered that there was room for further improvement regarding the breakage of the strip 4. In particular, in the case of an ultra-low flat tire such as the present embodiment having a small tire cross-section height, the tire lever f tended to contact the side surface of the strip 4 more frequently.

  And when further experiments were repeated, as shown in FIG. 5, in the meridian cross section including the tire rotation axis, the belt-like body 4 has at least one peak portion 10 extending in the width direction with the maximum thickness, and The free surface includes a tapered portion 12 provided on both sides of the crest portion 10 and gradually decreasing in thickness, and at least one trough portion 11 connected to the tapered portion 12 and extending in the width direction with a minimum thickness. It has been found that it is very effective to make 4B trapezoidal.

  The peak portion 10 is a portion extending substantially continuously in the width direction at the maximum thickness tm, and the trough portion 11 is a portion extending continuously in the width direction with a minimum thickness ti. The tapered portion 12 is provided on both sides of the peak portion 10. The taper portion 12 of this embodiment is formed between the peak portion 10 and the valley portion 11. Since the fixed surface 4A of the belt-like body 4 forms a flat surface, the tapered portion 12 forms an inclined surface 13 that is smoothly inclined from the peak portion 10 in the free surface 4B.

  This inclined surface 13 can round the corner by providing an arc having a sufficiently small radius of curvature as compared with the entire length of the inclined surface 13 at the connecting portion with the peak portion 10 and / or the valley portion 11. Here, the radius of curvature sufficiently smaller than the total length of the inclined surface 13 is, for example, 42% or less, more preferably 35% or less of the total length of the inclined surface, in order to make the free surface 4B trapezoidal. More preferably, an arc having a radius of curvature of 20% or less is allowed.

  In the present invention, both ends K of the belt-like body 4 are constituted by the valley portion 11 or the tapered portion 12 having a thickness of 1.0 to 15.0 mm. In this embodiment, the belt-like body 4 with the valleys 11 positioned at both ends is shown. This is useful for preventing contact between the tire lever f and the strip 4. The trough 11 has a thickness ti of 1.0 to 15.0 mm, more preferably 3.0 to 10.0 mm, and even more preferably 4.0 to 7.0 mm. desirable. If the thickness ti is less than 1.0 mm, the productivity of the strip 4 is lowered. This point will be described in detail later. Moreover, when the thickness ti of the valley portion 11 exceeds 15.0 mm, both ends K of the strip 4 tend to easily interfere with the tire lever f.

  Moreover, the free surface 4B of the strip | belt-shaped body 4 is comprised by the said inclined surfaces 13 and 13 from the trough parts 11 and 11 of the both ends K to the peak part 10, respectively. As shown in FIG. 6, the inclined surface 13 removes a portion that easily interferes with the tire lever f that tilts in the tire lumen i when the tire 3 is removed from the rim 2. Therefore, the contact between the tire lever 3 and the strip 4 can be avoided as much as possible, and damage to the strip 4 can be effectively prevented.

  Further, the inclined surface 13 or the valley portion 11 as described above approximates the tangential direction of the arc-shaped locus fL drawn by the tip portion of the tire lever f. For this reason, even if the tire lever f contacts the strip 4, the frictional force between the tire lever f and the inclined surface 13 (or the valley 11) is small, and the tip of the tire lever f is the strip. 4 is difficult to bite into. Therefore, the strip 4 is peeled off from the tire 3 and significant damage to the strip 4 is effectively prevented.

  In addition, in the trapezoidal wave-like curve that determines the contour shape of the free surface 4B, if the total amplitude H (ie, tm-ti) is too small, the surface area of the free surface 4B is reduced and the resonance suppression effect in the tire lumen i is reduced. On the contrary, even if it is too large, the inclined surface 13 tends to be along the tire radial direction, which is not preferable. From such a viewpoint, the total amplitude H is preferably 4 to 40 mm, more preferably 5 to 35 mm, and still more preferably 10 to 35 mm.

  Moreover, the free surface 4B of this embodiment has a trapezoidal wave shape having one peak portion 10 between the valley portions 11 and 11 at both ends K, that is, having a length of one period or more. However, as shown in FIG. 7, it may be configured by one peak portion 10, tapered portions 12 and 12 on both sides thereof, and a valley portion 11 connected to only one of the tapered portions 12. The belt-like body 4 is configured such that one end K is a trough 11 and the other end K is a taper 12. Each thickness at the end K is 1.0 to 15.0 mm. Also in such an embodiment, as described above, interference with the tire lever f can be effectively prevented.

  As shown in FIGS. 8 and 9, the belt-like body 4 may have two ridges 10 and one trough 11 between them. In such an embodiment, the free surface 4B of the belt-like body 5 is formed in a trapezoidal wave shape having a length of two periods, and can exhibit a higher resonance suppression effect. The belt-like body 4 shown in FIG. 8 has both ends K constituted by valleys 11, and the belt-like body 4 shown in FIG. 9 has both ends K constituted by taper portions 12. Although not shown in the figure, also in such an embodiment having two ridges 10, one end K is constituted by a trough 11 and the other end K is constituted by a taper 12 similarly to FIG. You can also.

  Moreover, such a strip | belt-shaped body 4 has the trough part 11 extended in the tire circumferential direction near the center part of the width direction. When the tire lever f comes into contact with the inclined surface 13 on the end portion side, the valley portion 11 promotes the deformation of the mountain portion 10 and releases the belt-like body 4 from the tire lever, whereby the tire lever f to the belt-like body 4 is obtained. Can be prevented. Therefore, it helps to prevent the belt 4 from being seriously damaged. Further, the trough 11 increases the surface area of the strip 4 and has a chance to make more contact with the air in the tire lumen i, effectively reducing the cavity resonance and enhancing the heat dissipation effect. It is also useful to prevent thermal destruction of the material.

  The volume of the belt-like body 4 is limited to a constant ratio with respect to the total volume of the tire lumen i. For this reason, if the length in the circumferential direction of the strip 4 is determined, the cross-sectional area per unit length is determined, and further restrictions such as the maximum thickness tm are added, and the shape of the side surface is determined, The width W1 of the fixed surface 4A can be determined naturally. However, if the width W1 of the fixed surface 4A is too large, the workability of attaching to the tire inner surface 3i tends to deteriorate as described above. From such a viewpoint, when the tire 3 is a passenger car radial tire, the width W1 of the fixing surface 4B of the strip 4 is preferably 30 to 250 mm, more preferably about 60 to 140 mm. This is desirably 5 to 100%, more preferably 20 to 70% of the tread width TW.

  The belt-like body 4 and the tire inner side surface 3i or the rim inner side surface 2i can be fixed by various methods. From the viewpoint of bonding cost and workability, it is particularly preferable to use an adhesive or a double-sided pressure-sensitive adhesive tape. In this embodiment, although the aspect fixed to the tire inner surface 3i by the double-sided pressure-sensitive adhesive tape 16 is shown, other than these, for example, a method using a screw, a mounting bracket, or the like, a method of integrating in a vulcanization process, or the like can be adopted. . And the pneumatic tire 3 and the strip | belt-shaped body 4 are adhere | attached previously, These can also be set-sold as a composite_body | complex of the pneumatic tire 3 and the strip | belt-shaped body 4. In order to improve the adhesion to the belt-like body 4, it is desirable that the tire inner side surface 3i be finished smooth. Usually, the tire lumen surface 3i is formed with protrusions formed by inverting and transferring the air vent groove of the bladder used during vulcanization, but this may be removed by polishing and smoothed. desirable. In addition, by using a smooth surface with no exhaust groove on the surface, the tire lumen surface can be flattened from the beginning. Particularly preferably, the pneumatic tire is vulcanized and molded without using an inside paint (release agent) on the tire lumen surface 3i. Thereby, the adhesiveness between the tire lumen surface 3i and the adhesive or the like is further improved.

Next, a preferred method for manufacturing the strip 4 will be described.
As shown in FIG. 10A, a flat sponge material S having a constant thickness T and having a substantially parallel first surface P1 and second surface P2 is prepared. The sponge material of the present embodiment has a rectangular shape.

  Next, for example, as shown in FIG. 10B, the sponge material S is stopped so that the blade 18 becomes a trapezoidal wavy cut surface 19 between the first surface P1 and the second surface P2. The so-called contour processing step of continuously slicing the sponge material is performed. The blade 18 has a blade span longer than the width of the sponge material S, and preferably a cutting blade such as a split blade that can physically cut the sponge material at room temperature. A blade that is thermally cut using a high-temperature wire or the like is not preferred because it tends to melt the surface of the sponge material S and close the pores to impair the sound absorption effect.

  In this embodiment, two slice materials Sa and Sb having substantially the same shape are obtained from one sponge material S by such a contouring process. As shown in FIG. 10B, the slice materials Sa and Sb are obtained in a state where the crests 10 and the troughs 11 face each other. In other words, in each of the slice materials Sa and Sb, the sum (tm + ti) of the thickness tm of the peak portion 10 and the thickness ti of the valley portion 11 is equal to the thickness T of the sponge material S.

  Next, as shown in FIG. 10C, one of the double-sided pressure-sensitive adhesive sheets 23 is provided on almost the entire areas of the first surface P1 and the second surface P2 forming the flat shape of the slice materials Sa and Sb. A double-sided pressure-sensitive adhesive sheet batch attaching step for attaching the surface is performed. In FIG. 10C, only one slice material Sb is shown, but the same can be done for the other slice material Sa.

  Next, the slice material Sb to which the double-sided pressure-sensitive adhesive sheet 23 is attached is cut together with the double-sided pressure-sensitive adhesive sheet along the direction C parallel to the longitudinal direction of the blade 18 in the valley 11 where the thickness is small, A dividing step for obtaining a plurality of strips 4 as shown in FIG. Thereby, many long strip | belt-shaped bodies 4 can be efficiently taken from one flat sponge material S. FIG. The width of the strip 4 along the direction C (in this embodiment, this length is the length in the tire circumferential direction) is cut at the stage of the flat sponge material S according to the size of the tire to be used in advance. In addition, after the dividing step, a cutting process or the like may be appropriately performed to adjust the length. Moreover, the process etc. which provide a taper part in both ends can be suitably performed to the both ends of the strip | belt-shaped body 4 as needed.

  As shown in FIG. 10D, the belt-like body 4 formed through such a manufacturing method has a peak portion 10, a valley portion 11, and a taper portion, and its free surface 4B is wavy in a trapezoidal shape in the width direction. Moreover, since at least one valley portion 11 is provided at both ends in this example, it can be suitably used for the pneumatic tire and rim assembly 1 of the present invention. Moreover, since the strip | belt body 4 formed by the said manufacturing method can take many strip | belt bodies of the substantially same shape from sponge material S efficiently, productivity can improve and the yield of material can also be improved. Therefore, a strip can be provided at low cost. Further, for example, in order to obtain the belt-like body 4 having two peak portions 11, it is only necessary to cut every other trough portion 11.

  In addition, including the case where the belt-like body 4 is formed by performing such a contour processing step, if the minimum thickness of the valley portion 11 is less than 1.0 mm, the valley portion 11 is obtained at the stage of obtaining the cut sponge materials Sa and Sb. It is easy to impair the durability of the belt-like body 4 such as breaking. In this case, the single-sided double-sided pressure-sensitive adhesive sheet 23 for attaching the single double-sided pressure-sensitive adhesive sheet 23 to almost the entire area of the first surface P1 or the second surface P2 cannot be performed, and the double-sided pressure-sensitive adhesive sheet is pasted on each strip 4. It must be attached and it is easy to lose productivity.

  Further, in order to most effectively cut a large number of strips 4 from a single sponge material, the strips 4 have a sum of widths Wt of less than 0 mm when valleys 11 are provided at both ends K. It is desirable that the sum of the width Wt of the large peak portion 10 or less, more preferably the width Wt of the valley portions 11 at both ends is substantially equal to the width Wy of the single peak portion 10. Most preferably, the widths Wt of the valleys at both ends should be made equal. In addition, such a strip | belt-shaped body 4 can be obtained by performing the division | segmentation in the intermediate position of the width | variety of the trough part 11 in slice material Sa and Sb of FIG.10 (C), and improves the yield of material further. sell. However, the strip 4 used in the present invention is not limited to such an embodiment.

  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 pneumatic tire and rim assembly was prototyped and tested for noise performance and damage to the strip when the tire was removed. In all the assemblies, 235 / 45ZR17 low-flat radial tires for passenger cars were used for pneumatic tires, and 17 × 7.5JJ aluminum wheel rims were used for rims. The pneumatic tire was vulcanized without using an inside paint (release agent) on the tire cavity surface. In addition, a bladder having an exhaust groove on its surface was used as a bladder for molding the tire inner surface. For this reason, the tire lumen surface is finished flat, and good adhesion to the belt-like body is obtained.

As the strip, an ether polyurethane sponge (product number E16, Maruzu Co., Ltd.) having a specific gravity of 0.016 is used, the length of each is 185 cm, and both ends in the tire circumferential direction are 45 as shown in FIG. The taper was cut at an angle of °. In each example, the total volume of the tire lumen is 26154 cm ³ . The volume, cross-sectional shape, and the like of the band-like body in each example are as shown in Table 1 and FIG. 11 (the unit of numerical values in the figure is millimeters). Further, the belt-like body and the tire inner surface (tread inner surface) were bonded using a double-sided adhesive tape (manufactured by Nitto Denko Corporation, model 5000NS). In addition, Examples 1-8 are all formed through a contouring process, and Example 7 cuts the troughs on both sides to reduce the width thereof. In Example 8, The troughs on both sides are cut at full width to form tapered portions at both ends.
The test method is as follows.

<Noise performance>
When the rim is assembled at an internal pressure of 200 kPa and mounted on all wheels of a vehicle (a domestic FR vehicle with a displacement of 3000 cm ³ ), traveling on a road noise measurement road (asphalt rough road) at a speed of 60 km / H with one passenger Car interior noise is measured at the driver's window side ear position, and the sound pressure level of the peak value of the air column resonance around 230 Hz is used as a reference for the vehicle interior noise of Comparative Example 1 (an assembly without a strip). It was shown by the increased or decreased value.

<Durability of strip when removing tire>
Using a tire changer (manufacturer name: EIWA, model: WING320) and a tire lever, an operation of removing the tire of the assembly from the rim was performed. 20 assemblies were prepared and removed by 20 workers. In the evaluation, the number of assemblies in which the belt-like body was damaged such as cuts and tears and the number of assemblies in which the belt-like body was peeled off from the inner surface of the tire were measured.

<Cost of strip>
The manufacturing cost for producing the strips for 100 assemblies was indicated by an index with Comparative Example 2 as 100. The smaller the value, the better.

  In addition, the strip | belt-shaped body of the comparative example 2 affixed the single-sided double-sided adhesive sheet 23 on the whole area of one surface of the flat sponge material S, as shown to FIG. 12 (A), (B), (C) is cut into a long body, and thereafter, both ends are tapered as shown in FIG.

In addition, as shown in FIGS. 13A and 13B, the band-like body of Comparative Example 3 is obtained by cutting a flat sponge material S into long bodies, and further cutting each long body with an inclined surface 13 with a cutter. After that, the double-sided adhesive tape 28 was attached.
Table 1 shows the test results.

The test results are briefly described below.
<Comparative example 2>
The strip of Comparative Example 2 is suitable for mass production. Therefore, a large amount can be supplied at low cost. However, the band-shaped body easily interferes with the tire lever, and the conventional drawback that many damage and peeling occur cannot be solved.

<Comparative Example 3>
Comparative Example 3 can be evaluated in that it has excellent noise performance and there is almost no damage to the belt-like body even when the tire is replaced. However, since the thickness of both end portions of the belt-like body is zero, as shown in FIGS. 13B and 13C, first, a long body is formed, and the slanted surface processing and double-sided adhesion are performed for each of the long bodies. It is necessary to attach a sheet. For this reason, it turns out that the manufacturing cost of a strip | belt shaped object is high, and is unsuitable for mass production. In particular, as shown in FIG. 13C, the amount of sponge discarded due to the processing of the inclined surface is large, and the yield is extremely poor.

<Examples 1-8>
In the assembly of the example, the noise performance was excellent, the belt-shaped body was hardly damaged even when the tire was replaced, and the strip-shaped body could be formed at a low cost, and the most preferable result was confirmed.

It is sectional drawing of the assembly of the pneumatic tire and rim | limb of this invention. It is the AA end elevation. It is an expanded sectional view of the composite of a tire and a strip. It is a graph which shows the relationship between the volume of a strip | belt shaped object, and a road noise reduction allowance. It is an enlarged view of the strip | belt shaped object of FIG. It is a principal part expanded sectional view which shows the tilting state of the tire lever in a tire lumen. It is sectional drawing which shows other embodiment of a strip | belt shaped object. It is sectional drawing which shows other embodiment of a strip | belt shaped object. It is sectional drawing which shows other embodiment of a strip | belt shaped object. (A)-(D) are the diagrams explaining the manufacturing method of a strip | belt shaped object. (A)-(F) It is sectional drawing which shows the strip | belt shaped object of an Example and a comparative example. (A)-(D) are explanatory drawings of the manufacturing method of the strip | belt-shaped body of the comparative example 2. FIG. (A)-(D) are explanatory drawings of the manufacturing method of the strip | belt-shaped body of the comparative example 3. FIG. It is a section schematic diagram explaining removal of a tire from a rim using a tire lever.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Assembly 2 Rim 2i Rim inner side surface 3 Pneumatic tire 3i Tire inner side surface 4 Band-shaped body 4A Fixed surface 4B Free surface 10 Mountain part 11 Valley part 12 Tapered part

Claims (8)

A rim, a pneumatic tire attached to the rim, a tire lumen surrounded by the rim and the pneumatic tire, and a tire extending in a circumferential direction and having a volume of 0.4 to the total volume of the tire lumen. An assembly of a pneumatic tire and a rim on which a belt-shaped body made of a sponge material that is 20% is arranged,
The strip has a maximum thickness of 5 to 45 (mm) from a fixed surface fixed to the inner surface of the tire or the inner surface of the rim to a free surface facing the tire lumen in a meridian cross section including the tire rotation axis. And the width of the fixed surface is larger than this thickness, making a horizontally flat shape,
In addition, the belt-like body has at least one peak portion extending in the width direction with the maximum thickness, a taper portion provided on both sides of the peak portion and gradually decreasing in thickness, and a minimum thickness connected to the taper portion. By including at least one valley portion extending in the width direction, the free surface of the band-like body has a trapezoidal wave shape,
A pneumatic tire and rim assembly characterized in that both ends of the belt-like body are formed of the valley or the taper having a thickness of 1.0 to 15.0 mm.   2. The pneumatic tire and rim assembly according to claim 1, wherein the belt-like body has valleys at both ends and has one peak between them.   The pneumatic tire and rim assembly according to claim 2, wherein the sum of the widths of the valleys is greater than 0 mm and less than or equal to the width of the peaks.   The pneumatic tire and rim assembly according to claim 2, wherein the band-like body has a sum of widths of the valleys substantially equal to a width of the peaks.   The pneumatic tire and rim assembly according to claim 1, wherein the belt-shaped body includes two peak portions and includes one valley portion therebetween.   The pneumatic tire and rim assembly according to claim 5, wherein both ends of the belt-like body are tapered portions.   A composite of a pneumatic tire and a belt-like body comprising a pneumatic tire and a belt-like body described in any one of claims 1 to 4 fixed to a tread inner surface of the pneumatic tire. A strip according to any one of claims 1 to 6,
By flatly slicing a flat sponge material having a substantially constant thickness along a trapezoidal corrugated cut surface along a first direction perpendicular to the thickness direction, one surface is flat. A contouring process for obtaining two slices having a shape of a trapezoidal wave on the other surface;
The slicing material is formed through a dividing step of dividing the sliced material along a second direction perpendicular to the first direction and the thickness direction at a valley portion forming the minimum thickness. A strip.

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