JP2001180217A - Assembly of pneumatic tire and rim - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce road noise. SOLUTION: In this assembly 1 of a pneumatic tire 2 and a rim 3, a tire inner cavity 4 is formed around the rim 3 by installing the tire 2 onto the rim 3. The assembly 1 has a noise damper 5. The noise damper 5 has a flexible annular band base body 6 mounted on the peripheral face of the rim 3; and one or more rising parts 7 formed in the band base body 6, rising to the tire radial direction from the peripheral face of the rim 3 by centrifugal force accompanying rotation of the assembly 1 to block the tire inner cavity 4. The band base body 6 comprises a first band base body part 6A disposed on the inner side of the tire radial direction and a second band base body part 6B disposed outside the first band base body part 6A. The second band base body part 6B is formed with an insertion part 17 allowing penetration and rise of the rising part 7 of the first band base body part 6A.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an assembly of a rim and a pneumatic tire, which can reduce road noise during traveling while improving rim assembly.

[0002]

2. Description of the Related Art In recent years, there has been a demand for lower noise and quieter vehicles. There are various types of noise generated by tires.
The so-called road noise that generates a “go” sound in the frequency range of 400 Hz is transmitted to the inside of the vehicle and becomes a muffled sound in the vehicle interior, giving the passenger discomfort. As a result of various experiments by the inventors, such road noise is caused when the tire is mounted on the rim, the tire lumen formed around the rim and formed by a cavity surrounded by the tire and the rim forms an air column tube. It is known that the fact that the air is undergoing resonance vibration (cavity resonance) has a great effect.

[0003] The applicant of the present application has proposed, for example,
Japanese Patent No. 14682 proposes disposing a shield made of a spherical body in the tire cavity to suppress such resonance.

[0004]

However, in the above method, the spherical body has a cross-sectional area of, for example, 40% of the tire lumen.
Since it has a size that blocks the above, there have been problems such as deterioration of the balance and dropping during transportation. The present invention has been devised in view of such a problem, and a flexible annular band base is mounted on the outer peripheral surface of a rim, and the rim is attached to the band base by centrifugal force accompanying rotation of an assembly. An assembly of a pneumatic tire and a rim that can reduce road noise without impairing the rim assembly of the tire, based on providing at least one rising portion that rises in the tire radial direction from the outer peripheral surface of the tire. It is intended to provide.

[0005]

The invention according to claim 1 of the present invention is an assembly of a rim and a pneumatic tire in which a tire cavity is formed around the rim by mounting the pneumatic tire on the rim. A flexible annular band base attached to the outer peripheral surface of the rim; and one or more of the flexible bases provided on the band base and rising in the tire radial direction by centrifugal force accompanying rotation of the assembly to block the tire bore. And a band suppressor having a rising portion, and wherein the band base is disposed on the innermost side in the tire radial direction having the rising portion.
And at least a second band base disposed radially outermost in the tire radial direction, and a rising portion of the first band base is provided in the second band base. A penetrating portion that can be raised through the portion is provided.

[0006] In such an assembly of a pneumatic tire and a rim, since the sound suppressor is constituted by a band base mounted on the outer peripheral surface of the rim, it does not hinder the rim assembling. There is no. In addition, during running, the rising portion provided on the band base rises in the tire radial direction due to centrifugal force, so that cavity resonance in the tire lumen can be suppressed and road noise can be reduced.

Further, the band base includes at least a first band base disposed radially innermost in the tire radial direction and a second band base disposed radially outermost in the tire radially having a rising portion. Since the second band base is provided with an insertion portion through which the rising portion of the first band base can penetrate through the second band base, the first band base and the second band base are provided. Since the rising portions provided on each of the band base portions can be raised in the tire lumen, a large number of rising portions can be easily provided in the tire lumen, which is useful for further reducing road noise.

Each of the band base portions has a width direction edge substantially continuous in parallel and of the same width, and each of the band base portions is spaced inward from the width direction edges on both sides thereof by the same distance X and at the same position in the circumferential direction. It has a U-shaped notch that is continuously connected by a horizontal notch between each end of a vertical notch extending in the same circumferential direction from the starting point, and the cut piece partitioned by this U-shaped notch rises due to centrifugal force. It is desirable to form the rising portion by the following method. Thus, the noise suppressor can be configured efficiently with a simple configuration. The distance X
Is 3 mm or more, the strength between the vertical cut and the width direction edge can be maintained, and a decrease in durability can be prevented.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view of an assembly of a pneumatic tire and a rim (hereinafter, may be simply referred to as an “assembly”) according to the present embodiment, FIG. 2 is a perspective view illustrating the sound suppressor, and FIG. The exploded plan view is shown. In the figure,
The assembly 1 is configured by mounting a pneumatic tire (hereinafter, may be simply referred to as a “tire”) 2 on a rim 3.
Tire bore 4 surrounded by tire 2 and rim 3 around rim 3
Is formed.

As shown in FIG. 1, the rim 3 of the present embodiment
Is a so-called two-piece wheel rim having, for example, a rim main body 3a on which the tire 2 is mounted and a disk 3b holding the rim main body 3a, and a bead portion 2a A rim bottom (also referred to as a well) 9 having a reduced outer diameter in order to drop the rim is formed. Further, the tire 2 of the present embodiment is assembled on a rim by bringing the bead portion 2a into close contact with the flange 10 of the rim main body 3a. The tire 2 is, for example, for a passenger car in which noise performance tends to be a problem, and has a tubeless structure in which a so-called inner liner rubber that hardly allows air to pass through is provided on the inner surface facing the tire cavity 4, and is airtight with the rim main body 3a. The tire cavity 4 is formed.

A sound suppressor 5 is mounted on the outer peripheral surface of the rim 3 in the tire radial direction. Sound suppressor 5 of the present embodiment
Is a flexible annular band base 6 mounted on the outer peripheral surface of the rim 3, and is provided on the band base 6. The centrifugal force accompanying the rotation of the assembly 1 causes the outer peripheral surface of the rim 3 to extend in the tire radial direction. One or more rising portions 7 that block the rising tire lumen 4
And is configured.

As shown in FIGS. 1 to 3, the band base 6 includes a first band base 6A disposed radially inward in the tire and a second band base disposed outside the band base 6A. 6A and 6B. Each of the band base portions 6A, 6B is made of a stretchable vulcanized rubber in this example,
For example, the rim 3 is stretched and attached to the outer peripheral surface of the rim 3 from one flange 10 side, in this example, the outer peripheral surface of the rim bottom portion 9 in a slightly stretched state, and is shown as an example. ing. The vulcanized rubber is not particularly limited. For example, natural rubber (NR), isoprene rubber (IR), butadiene rubber (BR), styrene butadiene rubber (SB)
R), nitrile rubber (NBR), chloroprene rubber (C
Diene rubbers such as R) are preferred. Especially NR, SBR
And the like are preferred.

If the thickness of each of the band base portions 6A and 6B is too large, the tension at the time of mounting the rim tends to be too large, and the rim assembling property tends to be deteriorated. There is a problem in terms of durability. From such a viewpoint, each of the band base portions 6A and 6B has, for example, a thickness of 0.5 to 3 mm, more preferably 0.5 to 2 mm, and still more preferably 1 to 3 mm (the thickness before the rim is attached). Desirably, it is about 2 mm. In this example, the band base portions 6A and 6B have their widthwise edges 6e and 6B, as shown in FIGS.
In FIG. 4, e has the same width BW (shown in FIG. 4) which is substantially parallel and continuous. Each of the band base portions 6A, 6B
Can be made substantially equal to the width of the rim bottom 9 of the rim 3, for example. Here, the width of the rim bottom 9 is, for example, a width RW (shown in FIG. 5) in which a small-diameter portion capable of dropping the bead portion 2a is substantially continuous. Each of the band base portions 6A and 6B has such a width BW, so that the band base portions 6A and 6B are attached to the outer peripheral surface of the rim bottom 9 and, for example, stay in the rim bottom 9 in combination with the small thickness, thereby further increasing the rim. Prevents the deterioration of assembly. The rim bottom 9 may be inclined at a small angle with respect to the tire axial direction.

When each of the band base portions 6A and 6B is made of vulcanized rubber as in this embodiment, for example, the ratio (Lb / Lb) of the circumferential length La before the rim is mounted and the circumferential length Lb when the rim is mounted. L
It is desirable that a) is larger than 1.0 and 1.3 or less, more preferably 1.08 to 1.16. Thereby, an effective tightening force or frictional force for attaching each band base portion 6A, 6B to the outer peripheral surface of the rim 3 can be given, and the attachment to the rim 3 becomes easy. Note that the ratio (Lb
/ La) is 1.0 or less, each band base portion 6A,
6B tends to loosen on the outer peripheral surface of the rim 3, so that the rising portion 7 is difficult to rise, and conversely, the ratio (Lb /
When La) exceeds 1.3, a large tension acts on each of the band base portions 6A and 6B during or during attachment to the rim 3, so that the band base portions 6A and 6B tend to be cut, and the durability tends to decrease.

The respective band base portions 6A and 6 of the present embodiment
B, as shown in FIG. 4, each end of a vertical cut 12 extending from the widthwise edge 6e on both sides inward in the width direction at a distance X in the width direction and extending from the same position in the circumferential direction to the same circumferential side as the starting point S. It has a substantially U-shaped notch 14 which is continuously connected between G and G by a horizontal notch 13, and each of the notch pieces 11 defined by the U-shaped notch 14 rises due to centrifugal force to form a cut. Rising parts 7A, 7B
(Note that reference numeral "7A" denotes a rising portion formed on the first band base portion 6A, and reference numeral "7B" denotes a rising portion formed on the second band base portion 6B. However, when they are collectively referred to, they are simply displayed as “rising portion 7”.) Thus, the rising portions 7A and 7A can be configured with a simple configuration, efficiently and inexpensively.
B can be formed on the first and second band base portions 6A and 6B to constitute the sound suppressor 5. The rising portion 7 is
As long as the cut piece 11 is made of rubber and does not transmit air, the cut piece 11 made of rubber can be used in various ways.

The distance X is, for example, 2 mm or more, more preferably 3 mm or more, so that each band base 6
The strength of the edge portion between the vertical cuts 12 and 12 of A and 6B and the width direction edge 6e can be maintained, and a decrease in durability can be prevented. The starting point S of the vertical cuts 12, 12
In this case, stress tends to concentrate when the cut piece 11 rises due to centrifugal force, and damage such as a crack is easily generated from the starting point S. In order to prevent such damage, the present embodiment exemplifies a preferred embodiment in which the starting point S is provided with a substantially circular hollow part 16 in order to prevent stress concentration on the starting point S. In this example, the hollow portion 16 has a circular shape with a diameter d with the center as the starting point S, and the diameter d is, for example, preferably 2 to 6 mm, more preferably 3 to 5 mm. It can also be. Further, such a hollow portion 16 is provided at the starting point S of the cut piece 11.
The base 11a on the side can be made smaller and its rigidity relatively weakened, so that it can be more easily started up.

In the present embodiment, the rising portion 7 of the first band base portion 6A is provided on the second band base portion 6B.
A has an insertion portion 17 that can be raised through the second band base portion 6B. In the present embodiment, the insertion portion 17 is formed by the U-shaped cut 14 of the second band base portion 6B. That is, as shown in FIGS. 2 and 3 in an exploded manner, the first band base portion 6A and the second band base portion 6B are formed in the same shape in this example, and the notches in the band base portions 6A and 6B are formed. Since the pieces 11 are mounted on the outer peripheral surface of the rim 3 while being aligned at the respective positions, the first band portion 6B of the second band base portion 6B is cut from the space in which the notch is formed in a U-shape to define the first band. The rising portion 7A of the band base portion 6A can be raised by penetrating the second band base portion 6B.

[0018] Such a noise suppressor 5 is used to connect the tire 2 to the rim 3.
When the rim is assembled, it is possible to attach the rim 3 to the outer peripheral surface of the rim 3 substantially flush.
Can be easily incorporated and the rim assemblability is not impaired.
In addition, while the assembly 1 is running, the noise suppressor 5
The rising portion 7 rises in the radial direction of the tire to block the air flow in the tire cavity, thereby suppressing cavity resonance and reducing road noise. In particular, in the present invention, a plurality of rising portions 7A and 7B are formed on a plurality of band base portions 6A and 6B overlapping in the tire radial direction, respectively, and these can be raised together in the tire lumen 4, so that a large number of rising portions 7 are used. As a result, it is possible to further suppress the resonance vibration in the tire inner cavity 4, and the road noise reduction width is increased. In the case of the above embodiment, a pair of rising portions 7 is provided.
A and 7B rise relatively close to each other. When the rising portions 7A and 7B are densely arranged as described above, for example, the road noise is larger than that in the case where only the rising portions 7A are provided. It has been found from various experiments that a reduction effect can be exhibited.

As shown in FIG. 6, the first band base portion 6A and the second band base portion 6B are formed in the same shape, and the positions of the cut pieces 11 in the tire circumferential direction are set to a distance Y. By shifting, each band base 6
The rising portions 7A, 7B of A, 6B can be raised from the outer peripheral surface of the rim 3 with the phases shifted in the tire circumferential direction. Also in this case, the rising portion 7A of the first band base portion 6A uses the space opened by the U-shaped notch 14 of the second band base portion 6B to insert the insertion portion 17A.
And the rising portion 7A of the first band base portion 6A is exposed outside of the second band base portion 6B in advance. In this mode, as shown in FIG. 7, it is effective to increase the number of the rising portions 7 in the tire radial direction while ensuring a large height in comparison with the circumferential length of the band base portion. Similarly, the tire lumen 4 can be efficiently shielded. Note that the phase shift amount Y can be set variously.

In the rising state, it is desirable that the height Ha in the tire radial direction, the width Wa in the tire axial direction, and the like be limited. FIG. 5 illustrates a meridional cross-sectional view of the assembly including the tire shaft when the tire is running under load. If the height Ha of the rising portion 7 is too small or the width Wa is too small, the effect of reducing the road noise is reduced. From such a viewpoint, the height Ha of the rising portion 7 is 85 to 100% of the tire lumen height H, which is the maximum height of the tire lumen when the tire is loaded, and the width Wa is the tire height when the tire is loaded. 20% or more of the maximum width W of the tire lumen is preferable in that the resonance in the tire lumen 4 can be more effectively prevented.

The normal running state of the tire under load varies variously depending on the load, the internal pressure, etc. In this specification, "when the tire is running under load" refers to the case where the tire 2 is mounted on the normal rim 3 and the normal internal pressure is maintained. Filling and regular load of 74
% Is defined as the state when a load is applied and pressed against a flat surface. Here, the “regular rim” is a rim defined for each tire in the standard system including the standard on which the tire is based. For example, a standard rim for JATMA, a “Design Rim” for TRA, Or ETRTO
Then "Measuring Rim".

The "regular internal pressure" is the air pressure specified 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" for TRA. LOAD LIMITS AT VARIOUS
Maximum value described in "COLD INFLATION PRESSURES", ETRT
If it is O, it is "INFLATION PRESSURE". However, if the tire is for a passenger car, the actual frequency of use etc. should be taken into consideration.
0 kPa. Further, the "regular load" is a load defined for each tire in the standard system including the standard on which the tire is based. For JATMA, the maximum load capacity, and for TRA, the table "TIRE LOAD LIMITS" AT VA
RIOUS COLD INFLATION PRESSURES "
For TRTO, use "LOAD CAPACITY".

Also, the ratio (Ab / As) of the cross-sectional area As (when no load is applied) in the cross section including the tire axis of the tire lumen 4 to the cross-sectional area Ab of the rising portion 7 included in one tire meridian cross section. ) Is desirably 5% or more, 10% or more, more preferably 15% or more, and still more preferably 20% or more, in that the road noise can be more effectively reduced.

FIG. 8 is a perspective view showing another embodiment of the band base 6 of the present invention, and FIG. 9 is an exploded development view thereof.
In this embodiment, the insertion portion 17 is formed by an opening different from the U-shaped cut 14 of the second band base portion 6B. First band base 6
The position of the rising portion 7A of the second band base portion 6A
B is determined in accordance with the position of the insertion portion 17 of B.
7, a rising portion 7A of the first band base portion 6A
Can be passed through the second band base portion 6B in advance and exposed to the outside. Also in this embodiment, each band base portion 6
The rising portions 7A, 7B of A, 6B can be arranged at a distance in the tire circumferential direction.

Although the embodiment of the present invention has been described above, it goes without saying that the present invention can be carried out in various modes, for example, the band base 6 may be composed of three or more band bases. No.

[0026]

EXAMPLES Tires (195 / 65R15) and rims (15
× 6JJ, rim bottom width: 55 mm, rim bottom circumference: 1
10 cm), an assembly of a pneumatic tire and a rim was prototyped using the above sound suppressor, and the noise performance and the like were evaluated. For comparison, an assembly (comparative example) other than the present invention, such as an assembly from which a sound suppressor was removed, was also trial-produced and tested. The first and second embodiments have the basic structure of the sound suppressor of FIG. 2, and the third and fourth embodiments have the basic structure of the sound suppressor of FIG. Further, the amount of deviation of the rising portions 7A and 7B in the tire circumferential direction in Example 3 was 20 mm, and that in Example 4 was 25 mm.
The deviation amount was set to substantially zero. The content of the test is as follows.

(Noise test) The rim was assembled at an internal pressure of 200 KPa and mounted on a 2000cc FR car manufactured in Japan. The speed of the road noise measurement road (asphalt rough road) was set to 6 by one passenger.
The sound inside the front seat when traveling at 0 km / H is passed through a 1/24 octave band filter to 226 Hz, 240 Hz,
The three-channel partial overall of 253 Hz was calculated, and evaluated by the increase / decrease value based on Comparative Example 1.

(Suitability of sound suppressor, rim assemblability) The wearability of the sound suppressor to the rim and the rim assemblability by hand assembly after attaching the sound suppressor to the rim were examined.

(Durability of the sound suppressor) The drum was run on the drum at an internal pressure of 200 KPa, a vertical load of 500 N, and a speed of 60 km / H for 1 hour, and the degree of damage to the sound suppressor and the state of occurrence of cracks were visually examined. Table 1 shows the test results and the like.

[0030]

[Table 1]

As a result of the test, it was confirmed that each of the assemblies of the example reduced the road noise as compared with the comparative example. Almost good results were also confirmed for the rim assemblability.

[0032]

As described above, in the assembly of the present invention, the rising portion of the sound suppressor rises in the tire radial direction from the outer peripheral surface of the rim using centrifugal force. The cavity resonance of the tire lumen can be suppressed without impairing the tire, and the road noise can be greatly reduced.
Further, the band base includes at least a first band base disposed radially innermost in the tire and a second band base disposed outermost in the tire radial direction, and further includes the second band base. The first band base portion has an insertion portion through which the rising portion of the first band base portion penetrates the second band base portion and can be raised, so that the first band base portion and the second band base portion are respectively provided. Since any of the provided rising portions can be raised in the tire cavity, a large number of rising portions can be easily provided, which helps to further reduce road noise.

[Brief description of the drawings]

FIG. 1 is a partial perspective view illustrating an assembly of a pneumatic tire and a rim according to an embodiment.

FIG. 2 is a perspective view illustrating a sound suppressor.

FIG. 3 is an exploded partial view of the band base.

FIG. 4 is an enlarged partial development view of a band base portion.

FIG. 5 is a cross-sectional view showing a state of the assembly during load running.

FIG. 6 is an exploded development view of a band base showing another embodiment of the present invention.

FIG. 7 is a schematic cross-sectional view of an assembly using the same in a tire circumferential direction.

FIG. 8 is a perspective view of a band base showing another embodiment of the present invention.

FIG. 9 is an exploded development view thereof.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 assembly 2 pneumatic tire 3 rim 5 sound suppressor 6 band base 6A first band base 6B second band base 7, 7A, 7B rising section 9 rim bottom 11 cut piece 12 vertical cut 13 horizontal cut 13 Notch 14 U-shaped notch 17 Insertion part

Claims (4)

[Claims] 1. An assembly of a rim and a pneumatic tire that forms a tire cavity around the rim by mounting the pneumatic tire on the rim, the flexible rim being mounted on an outer peripheral surface of the rim. A noise suppressor provided on the band base and having at least one rising portion that rises in a tire radial direction by a centrifugal force caused by rotation of the assembly and blocks a tire lumen; Includes at least a first band base portion disposed on the radially innermost side of the tire having the rising portion and a second band base portion disposed on the outermost side in the tire radial direction, and further includes the second band base. An assembly of a pneumatic tire and a rim, characterized in that an insertion portion is provided in the portion so that a rising portion of the first band base portion can penetrate through the second band base portion. 2. Each of the band base portions has a width direction edge substantially continuous in parallel and of the same width, and each of the band base portions is separated from the width direction edges on both sides thereof by a distance X inward and in a circumferential direction. It has a U-shaped notch that is continuously connected by a horizontal notch between each end of a vertical notch that extends in the same substantially circumferential direction from the same position as a starting point, and the cut piece partitioned by this U-shaped notch is centrifugal force The pneumatic tire and rim assembly according to claim 1, wherein the rising portion is formed by standing up. 3. The pneumatic tire and rim assembly according to claim 2, wherein said insertion portion is formed by said U-shaped cut of said second band base portion. 4. The combination of a pneumatic tire and a rim according to claim 2, wherein said insertion portion is formed with an opening different from said U-shaped cut of said second band base portion. Three-dimensional.