JP2000343912A - Tire having damper part - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce road noise and improve comfortableness and operation stability by at least providing extended parts extending from bead parts to the inside in the width direction of a tire, and providing a mounting part to a wheel and a damper part connecting together the mounting part and the bead part on the extended part. SOLUTION: A tire 10 is provided with a tread part 11 having both end parts in the width direction, side wall parts 12 connected to both end parts in the width direction of the tread part 11, respective bead parts 13 connected to the respective side wall parts 12, and extended parts 14 extending from the respective bead parts 13 to the inside in the width direction of the tire. The each extended part 14 is provided with a mounting part 15 to a wheel 20, and a damper part 16 connecting together the mounting part 15 and the bead part 13. Hereby by tuning the spring constant in the vertical direction of the damper part 16, comfortableness can be improved. Further because the damper part 16 is flexible construction, the tread part 11 is hardly floated up from the ground surface, and improvement of road surface gripping property, restraint of rutting, and improvement of operation stability can be attained.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a tire having a damper portion.

[0002]

2. Description of the Related Art In recent years, reducing the fuel consumption of automobiles has become an important issue from the viewpoint of protecting the global environment, and there is a strong demand for reducing the rolling resistance of tires. Although there are various means, the method of suppressing the deflection of the sidewall portion of the tire is particularly effective, and a high-pneumatic tire, a low-profile tire having a low height, that is, a small difference in inner and outer diameters, and a thickness of the sidewall are large. The adoption of tires and the like with increased weight is increasing.

[0003]

However, in the tire in which the deflection of the side wall portion is suppressed, the role of the tire in reducing the transmission of vibration from the road surface to the vehicle body, which has been achieved by the tire, is reduced. The ride quality deteriorates (so-called lumpy feeling). The cause is that the vertical vibration in the region of 10 Hz or more is less attenuated than that of a normal tire. For the same reason, road noise (noise when traveling on the road surface) worsens. 200 ~ 30 due to car structure
There is a resonance point at 0 Hz. Drivability is generally improved by increasing the cornering force of the tires, but the camber thrust is reduced and rutability is worsened. In addition, a wheel having a combination of a normal tire and a wheel which is separate from each other generally has the following problem. In order to compensate for unbalance and uniformity, it is necessary to install balance weights and work to balance them. When the rim flange is deformed due to collision with a curb, it is necessary to adopt a structure in which air leakage of the tire does not occur or hardly occurs, and the rim thickness increases. At the time of a sharp turn or the like, the rim comes into contact with the road surface, and measures to prevent the vehicle from rolling over are required. An object of the present invention is to provide a tire having a damper portion, which can improve the ride quality. Another object of the present invention is to provide a tire having a damper portion, which can improve the riding comfort and reduce road noise. Another object of the present invention is to provide a tire having a damper portion, which can improve the riding comfort and the operability.
Another object of the present invention is to improve ride comfort,
An object of the present invention is to provide a tire having a damper portion, which can achieve automatic alignment. Another object of the present invention is to provide a tire having a damper portion, which can improve the ride comfort and suppress the problem of rim deformation at the time of a curb collision. Another object of the present invention is to provide a tire having a damper portion, which can improve the riding comfort and prevent the vehicle from rolling over due to a rim touch during a sharp turn.

[0004]

The present invention to achieve the above object is as follows. (1) It has a tread portion, a sidewall portion connected to the tread portion, a bead portion connected to the sidewall portion, and an extension portion extending inward in the tire axial direction from the bead portion, wherein the extension portion is a portion attached to a wheel. A tire having a damper part connecting the mounting part and the bead part. (2) A tread portion, a sidewall portion connected to the tread portion, and an extension portion connected to the sidewall portion and extending inward in the tire axial direction, wherein the extension portion is a mounting portion to a wheel, and the mounting portion and the sidewall. A tire having a damper part connecting the parts.

In the tire having the damper portion (1) or (2), the vertical spring constant of the damper portion of the vibration system having the vehicle body as a mass and the damper portion as a spring is 10H.
By tuning for vibration attenuation of z or more, for example, 10 to 20 Hz, riding comfort is improved (10 to 2
The stiffness in the 0 Hz range is lost). In addition, the damper part is a spring, the tread part, the sidewall part,
Considering the vibration system with the (bead part) as a mass, tuning the spring constant of the damper part causes a problem in road noise 2
Vibration transmission in the range of 00 to 300 Hz can be reduced, and noise can be reduced. Also, the damper part is flexible,
Since the tire tread portion deforms following the road surface shape, grip is improved, rutting is suppressed, and maneuverability is improved. In addition, since the damper part is flexible, the wheel with tire rotates by selecting the center of rotation by itself, that is, it has an automatic alignment function, so there is no need to install balance weights and balance work for unbalance and uniformity compensation Becomes In addition, since the extended portion is provided, the rim flange hardly collides with the curb, and there is no or less problem of deformation of the rim flange and air leakage when colliding with the curb. In addition, because of the extended portion, road contact (rim touch) of the rim flange does not occur or hardly occurs at the time of a sharp turn of the vehicle, and there is no problem such as vehicle rollover due to the rim touch.

[0006]

FIG. 1 shows a structure in which a tire having a damper portion according to a first embodiment of the present invention is mounted on a wheel. FIG. 2 shows a tire having a damper portion according to a second embodiment of the present invention. 2 shows a structure in which is mounted on a wheel. FIG.
FIG. 7 to FIG. 7 show characteristics applicable to any of the embodiments of the present invention. Portions common or similar to the first and second embodiments of the present invention are denoted by the same reference numerals throughout the first and second embodiments of the present invention. First, portions common or similar to the first and second embodiments of the present invention will be described with reference to FIG.

In FIG. 1, a tire 10 having a damper portion according to the present invention is mounted on a normal wheel 20. The tire 10 is pressed against the wheel 20 by the air pressure of the tire at a mounting portion to the wheel 20. The tire 10 is not vulcanized and bonded to the wheel. Therefore, if the air pressure is released, the tire 10 can be separated from the wheel 20. Tire 10 having damper part of the present invention
Is a rubber (including a steel cord embedded), and the wheel 20 is a metal, for example, an aluminum alloy or steel, or a hard resin. The tire 10 having the damper portion is continuous over the entire circumference in the circumferential direction.

The tire 10 is symmetrical or substantially symmetrical with respect to a center line passing through the center in the tire width direction (tire axial direction). The tire 10 includes a tread portion 11 (having one) having both ends in the width direction, and a sidewall portion 12 (having two) connected to each end of the tread portion 11 in the width direction.
Each of the bead portions 13 (there are two) connected to each of the sidewall portions 12, and the extending portions 14 (there are two) extending inward in the tire axial direction from the respective bead portions 13. Here, the bead portion 13 may not be necessarily provided, and when the bead portion 13 is not provided, the extension portion 14 is directly connected to the sidewall portion 12.

Each extending portion 14 has a mounting portion 15 to be mounted on the wheel 20, and a damper portion 16 for connecting the mounting portion 15 to the bead portion 13 (the sidewall portion 12 when there is no bead portion 13). . The two connecting portions 15 are separated in the tire width direction. The mounting portion 15 extends inward in the tire axial direction and inward in the tire radial direction from the inner end in the tire axial direction of the damper portion 16. The mounting portion 15 is pressed against the bead seat portion and the flange portion of the rim of the wheel 20 to seal the tire and the wheel.

The wheel 20 is a normal (current product, having the same standard dimensions as a conventional product), and is made of a steel wheel or an aluminum wheel. Therefore, a conventional product can be used for the wheel 20 without changing the design. Since the tire 10 has the damper portion 16, only the tire 10 is different in shape and size from the conventional tire. The wheel 20 has a disk 21 and a rim 22, and the disk 21
The rim 22 and the rim 22 may be integrally formed with each other, or may be separately manufactured and integrally joined by welding. The tire 10 is mounted on a wheel 20 at a rim 22 site. The disc 21 has a hub hole 23 and a bolt hole 24.
Are formed. The rim 22 has flange portions 25a and 25b located at both ends in the axial direction (a is the front side, b is the back side).
And bead seat portions 26a and 26b (a is a front side, b is a back side) connected to the flange portions 25a and 25b, and a drop portion 27. The wheel 20 has an air valve hole for mounting the air valve 28.

The rigidity of each part of the tire 10 is determined by its shape, material,
It can be freely selected according to the site by embedding a steel cord. The damper portion 16 is a portion that is softer than the mounting portion 15 and the bead portion 13 and can function as a spring and a damper.

The spring of the damper portion 16 acts as a shear or a tension or a bend or a combination of at least two of these. The vertical constant of the damper part 16 is:
In a vibration system in which the vehicle body is a mass and the damper portion 16 is a spring, the spring constant is selected to be able to attenuate the vertical vibration at about 10 to 20 Hz, for example, about 15 Hz. Since the resonance point is in a lower frequency range than the damping region, in a vibration system in which the vehicle body is a mass and the damper portion 16 is a spring, the resonance point is 8 Hz to 1 in order to attenuate a vertical vibration near 15 Hz.
It is set in a region of about 0 Hz.

By tuning the resonance point of a vibration model with a tire as a mass to 120 to 180 Hz by using the damper section 16 whose spring constant is selected as described above, a conventional problem of 200 to 300 Hz has been obtained. For example, road noise near 230 Hz (a humming sound when traveling on a road surface) can be suppressed (to suppress vibration in a region slightly above the resonance point).

The tire 10 may be provided with a run flat portion extending toward the tread portion 11 on the mounting portion 15 or by hardening the tire sidewall portion 12 so that the sidewall portion 12 has a run flat mechanism. Is also good. When the run flat portion is formed or when the tire sidewall portion 12 is hardened, it is safe to run for a while in a state where the tire is punctured.

Next, the operation of the parts common to all the embodiments of the present invention will be described. First, in the tire having the damper part of the present invention, the vertical spring constant of the damper part 16 is set to a value of 10 Hz or more, for example, a vibration of about 15 Hz of a vibration system using the vehicle body as the mass M and the damper part 16 as the spring K. By tuning for damping (by setting the spring constant of the damper portion 16 to a resonance frequency of about 8 to 10 Hz), the riding comfort is improved, and a so-called rugged feeling in a frequency range of 10 Hz or more, for example, around 15 Hz. Reduced.

This will be further described as follows. FIG. 4 shows a vibration model when the mass of the vehicle is M and the vertical shearing spring constant of the rubber member 30 is K. The resonance frequency f of this vibration model is f = (1 / 2π) · (K / M) ^1/2 . In order to create a system in which the resonance point is 10 Hz slightly below the target frequency for reduction, K = 1611 N / mm is obtained from the above equation, which is a dynamic spring constant, and the static spring constant Ks of the same damper is considerably larger than this. Small, 1300 N / mm
About. The amount of deflection when a load of 400 kgf is applied to this spring is about 3 mm (see FIG. 3). In a conventional wheel with a damper, compressed rubber is used in order to minimize this bending, but in the embodiment of the present invention, the damper portion 16 is provided on the tire 10 on the assumption that this bending is allowed. FIG. 5 shows the vibration characteristics of the above vibration system. In the frequency range slightly above the resonance point (10 Hz or more, for example, in the vicinity of 15 Hz), the vibration can be reduced and the vibration transmission can be reduced.

Since the damper portion 16 can be deformed without restricting its volume with respect to the vertical vibration, the load / displacement characteristics of the spring are linear as shown in FIG. FIG. 3 also shows the non-linear characteristics of the compressed rubber of the conventional damper. A normal size car load (eg, 4
In the state in which the pressure applied to the damper portion 16 is 3 mm, the spring is bent by 3 mm in the initial state, and in the vicinity of the 3 mm displacement point, the gradient of the conventional compression spring is steep and the spring is hard. In this case, the linear spring is relatively gentle and soft over the entire range of displacement, and is 10 Hz or more, for example, 15 Hz regardless of the load.
Vibrations at front and rear frequencies can be effectively suppressed.

FIG. 6 shows vertical acceleration on a sprung portion (driver's seat rail portion) in a low frequency range when an actual automobile is mounted on a road with a tire or a tire according to the present invention and the vehicle travels on a rough road. (DB display) vs. frequency (H
z) shows the actually measured values. As is clear from FIG.
In the tire having the damper portion of the embodiment of the present invention, 10 to 10
A significant acceleration reduction is seen in the region of 20 Hz. Correspondingly, in the actual traveling, the rugged feeling at 10 Hz or more, for example, around 15 Hz during traveling is eliminated.

In the tire having the damper portion according to the embodiment of the present invention, the tread portion 11, the sidewall portion 12, and the bead portion 13 of the tire 10 are considered to have a mass m (m = mass corresponding to a load of about 20 kgf). The resonance point of the vibration model in which the damper portion 16 has the spring K (the dynamic spring constant is high in a high frequency region and is estimated to be about 2600 N / mm) is near 180 Hz, and the frequency is slightly higher than that. Area 2
Road noises around 100 to 300 Hz, for example, around 230 Hz (a humming noise when traveling on a road surface) can be suppressed (to attenuate vibration in a region slightly above the resonance point). Here, the road noise is a sound that is transmitted from the road surface to the body and vibrates the body panel to be a sound, and this sound overlaps with the air column resonance of the passenger compartment. There is a resonance point at ~ 300 Hz.
FIG. 7 shows a vehicle interior noise (dB display) versus frequency (Hz) characteristic in a high frequency region. As can be seen from FIG. 7, when the tire having the damper portion of the embodiment of the present invention is mounted and the vehicle runs on a road surface, the road noise at 200 to 300 Hz, for example, near 230 Hz is more effective than the wheel with the normal tire. Has been reduced to this is,
When an integrated wave having a large number of frequencies is input to a vehicle having multiple resonance points such as an automobile, the vibration system at the resonance point near 180 Hz selectively resonates, and 200 to 300 slightly above the resonance system.
Hz, for example, around 230 Hz.

Further, since the vibration entering the vehicle body can be counteracted by the tire damper section 16, this is a countermeasure against headwater flow, and is a fundamental vibration countermeasure as compared with the case where the countermeasure is performed on the vehicle body side after entering the vehicle body. In the countermeasures after entering the vehicle body, in the case of a car having a multi-resonance point body, the countermeasures are different for each vehicle and are generally expensive and heavy, and it is difficult to take measures against vibration.

Further, in the tire having the damper portion according to the embodiment of the present invention, since the damper portion 16 has a flexible structure, the tread portion 11 of the tire 10 is hard to float from the ground, the road surface grip of the tread portion 11 is improved, and Is suppressed and maneuverability is improved. In the tire having the damper portion according to the embodiment of the present invention, since the damper portion 16 has a flexible structure, the wheel on which the tire is mounted has its own center of rotation selected during rotation, and has a self-aligning function. As a result, there is no need to attach a balance weight or balance work for compensating for unbalance and uniformity, which is conventionally required.

In the tire having the damper portion according to the embodiment of the present invention, since the extension portion 14 is provided, when the wheel collides with the curb, the rim flange portion collides with the curb only by the tire colliding with the curb. Rim flange is not deformed, and there is no problem of air leakage occurring when the rim flange is deformed. Also,
In the tire having the damper portion of the present invention, since the extending portion 14 is located on the outer peripheral side of the rim flange, there is no problem such as the vehicle rolling over due to road contact (rim touch) of the rim flange when the vehicle turns.

In the tire having a damper portion according to the embodiment of the present invention, if a run flat portion extending toward the tread portion 11 is formed in the mounting portion 15 of the tire 10, When the tire is hardened, the car can run for a while while suppressing excessive deformation even if the tire is punctured.

Next, parts unique to each embodiment of the present invention will be described. In the first embodiment of the present invention, as shown in FIG. 1, the tire 10 has a bead portion 13, and the extending portion 14 extends from the bead portion 13 toward the widthwise center of the tire 10. The damper part 16 is located between the mounting part 15 and the bead part 13. The damper part 16 is on the inner peripheral side,
The flange of the wheel rim is located. Mounting part 15
Has almost the same shape as the bead portion of the conventional tire.
The structure of the wheel 20 is the same as the structure of the current product (conventional product).

In the second embodiment of the present invention, as shown in FIG. 2, the tire 10 does not have the bead portion 13, and the extending portion 14 is located at the center of the tire 10 in the width direction from the sidewall portion 12. Extending towards. The damper part 16 is located between the mounting part 15 and the sidewall part 12. The flange portion of the wheel rim is located on the inner peripheral side of the damper portion 16. The mounting portion 15 has substantially the same shape as the bead portion of the conventional tire. The structure of the wheel 20 is the same as the structure of the current product (conventional product).

[0026]

According to the tire having the damper portion according to claim 1 or 2, the vertical spring constant of the damper portion of the vibration system having the vehicle body as the mass and the damper portion as the spring is
By tuning for vibration attenuation of 10 Hz or more, for example, 10 to 20 Hz, riding comfort is improved (1).
The rugged feeling in the 0 to 20 Hz range is lost). In consideration of a vibration system having a damper portion as a spring and a tread portion, a sidewall portion, and a (bead portion) as masses, a spring constant of the damper portion is tuned to transmit a vibration in a 200 to 300 Hz range which is a problem in road noise. And reduce noise. Further, since the damper portion has a flexible structure, the tire tread portion deforms following the road surface shape, so that grip is improved, rutting is suppressed, and maneuverability is improved. In addition, since the damper part is flexible, the wheel with tire rotates by selecting the center of rotation by itself, that is, it has an automatic alignment function, so there is no need to install balance weights and balance work for unbalance and uniformity compensation Becomes In addition, since the extended portion is provided, the rim flange hardly collides with the curb, and there is no or less problem of deformation of the rim flange and air leakage when colliding with the curb. In addition, since there is an extended portion, road contact (rim touch) of the rim flange does not occur or hardly occurs at the time of a sharp turn of the vehicle, and there is no problem such as rollover of the vehicle due to the rim touch.

[Brief description of the drawings]

FIG. 1 is a sectional view of a wheel equipped with a tire having a damper portion according to a first embodiment of the present invention.

FIG. 2 is a sectional view of a wheel equipped with a tire having a damper portion according to a second embodiment of the present invention.

FIG. 3 is a vibration model diagram of an automobile equipped with a tire having a damper portion according to the first and second embodiments of the present invention.

FIG. 4 is a diagram illustrating vibration transmission versus frequency characteristics of a tire having a damper portion according to the first and second embodiments of the present invention.

FIG. 5 is a spring characteristic diagram (load-displacement characteristic diagram) of a tire having a damper portion according to the first and second embodiments of the present invention.

FIG. 6 shows a low-frequency range (0) in a case where a tire having a damper portion according to the embodiment of the present invention is mounted on a rough road and a case where a conventional diamond without a damper portion is mounted and a rough road is run.
FIG. 7 is a characteristic diagram of vibration level (in dB) versus frequency (Hz) of a sprung portion (driver seat rail) at −45 Hz).

FIG. 7 shows a high-frequency region (1) in the case of running on a rough road with the tire having the damper portion according to the embodiment of the present invention mounted and in the case of running on a rough road with the conventional diamond without the damper portion mounted.
FIG. 4 is a noise level (dB display) vs. frequency (Hz) characteristic diagram at (00 to 500 Hz).

[Explanation of symbols]

 Reference Signs List 10 tire 11 tread part 12 sidewall part 13 bead part 14 extension part 15 mounting part 16 damper part 20 wheel 21 disk 22 rim 23 hub hole 24 bolt hole 25a, 25b flange part 26a, 26b bead seat part 27 drop part 28 air valve

Claims (2)

[Claims] 1. A tread portion, a sidewall portion connected to the tread portion, a bead portion connected to the sidewall portion, and an extension portion extending inward in the tire axial direction from the bead portion, wherein the extension portion is mounted on a wheel. A tire having a portion and a damper portion connecting the mounting portion and the bead portion. 2. A tread portion, a sidewall portion connected to the tread portion, and an extension portion connected to the sidewall portion and extending inward in the tire axial direction, wherein the extension portion has a mounting portion to a wheel, the mounting portion, A tire having a damper portion connecting a sidewall portion.