JPS63275404A - Tire with pneumatic rim - Google Patents

Abstract

PURPOSE:To reduce road noise in a simple and positive manner by providing each flat member having each specified width and thickness for either or both of the inner circumferential surface of a tread section or/and the outer circumferential surface of a rim between beads thereof. CONSTITUTION:A pair of a right and a left bead section 1 is incorporated within the rim 2 of a tire. In this case, each flat member 4u and 4d is arranged for either or both of the inner circumferential surface of a tread 3 or/and the outer circumferential surface of a rim 2 between each of beads 1. And the flat member 4u arranged at the tread section 3 is allowed to be of a width equivalent to the width T of the tread surface, and the flat member 4d arranged on the rim 2 is also allowed to be of a width equivalent to the linear distance between each of beads 1. Furthermore, the sum of each thickness H1 and H2 of respective flat members 4u and 4d is set up to be within 5 through 35% of the maximum height H0 or the tire.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a tire with a pneumatic rim that reduces road noise (vehicle interior noise).

[Prior art]

Conventionally, efforts have been made to reduce tire rigidity and increase tan δ of tread rubber in order to reduce road noise, but in this case, there are problems such as deterioration of steering stability and deterioration of fuel efficiency. . Also, JP-A-62-5
Publication No. 0203 discloses that a resonance blocking material is enclosed in an air filling portion inside a tire. However, since the dimensions of the resonance blocking material are unknown, the effectiveness of its use is not clear.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a tire with a pneumatic rim that reduces road noise, particularly road noise generated when an automobile runs on a rough road surface.

[Structure of the invention]

For this reason, the present invention consists of an assembly of a tire and a rim, and a flat member is disposed on either or both of the inner circumferential wall surface of the tread portion and the outer circumferential surface of the rim between the bead portions, and the trend portion The flat plate member installed on the inner peripheral wall surface has a width equivalent to the ground contact width of the tread, and the flat plate member installed on the outer peripheral surface of the rim between the bead parts has a width equivalent to the linear distance between the bead parts. The gist of the present invention is to provide a tire with a pneumatic rim, which is further characterized in that the sum of the thicknesses of these flat plate members is 5 to 35% of the maximum inner surface height of the tire.

Hereinafter, the configuration of the present invention will be explained in detail with reference to the drawings.

FIG. 1 is an explanatory cross-sectional view in the meridian direction of an example of a tire with a pneumatic rim according to the present invention. In FIG. 1, a pair of left and right bead portions 1. 1 is incorporated into the rim 2. Further, a flat member 4u is provided on the inner peripheral wall surface of the tread 3, while a flat member 4d is provided on the outer peripheral surface of the rim 2 between the bead portions 1,1.

Either or both of the flat plate members 4u and 4d may be provided. In addition, the total weight only needs to be sufficiently light compared to the weight of the tire and rim.If it is sufficiently light, it will not affect the overall weight of the tire with the rim. This is because the original function of the tire is not inhibited. These flat plate members 4u, 4d
is, for example, a porous material such as polyurethane foam. The flat plate members 4u and 4d are arranged, for example, on the inner peripheral wall surface of the trend 3 and the bead portion 1.1 through an adhesive.
This can be done by pasting it on the outer peripheral surface of the rim 2 between them.

The flat member 4u disposed on the inner circumferential wall surface of the trend portion 3 has a width corresponding to the ground contact width T of the tread surface. Further, a flat member 4 disposed on the outer peripheral surface of the rim 2 between the bead portions 1, 1
d has a width corresponding to the linear distance between the bead portions 1.1.

Furthermore, the thickness H8 of the flat plate member 4u and the thickness H of the flat plate member 4d! The sum (H1+H,) is 5 to 35% of the tire maximum inner surface height H8. The reason why it is set at 5 to 35% is to make the tire as light as possible. Further, if it exceeds 35%, the road noise reduction effect reaches a plateau, while if it is less than 5%, it is difficult to achieve the road noise reduction effect.

Next, tire size 205/65 R15 tires (
Figure 2 shows the results of evaluating the vibration transmissibility characteristics between the trend center part and the rim bolt hole in a single tire using a 6!4JJx15 rim with the structure shown in Figure 1 and an air pressure of 1.9 kgf/cd. . However, flat plate members 4u, 4d
As the material, polyurethane foam having an apparent specific gravity of 0.013 was used.

In addition, the frequency is the resonance frequency of tire vibration caused by compressional waves of the air filling part inside the tire (230 to 2
In FIG. 2, the transmission rate without polyurethane foam was set at 100.

From Figure 2, the thickness of polyurethane foam H1+Hz)/
When He is 0.05, the transmittance is less than half (approximately 40) of the transmittance without polyurethane foam, which is 0.21.
It becomes almost zero, and it can be seen that there is no change even when the temperature exceeds 0°35. Further, the same results were obtained when the vibration transmissibility characteristics were similarly evaluated using polyurethane foam having an apparent specific gravity of 0.016 as the flat plate members 4u and 4d.

Furthermore, regarding the tires used in the test shown in Figure 2,
Figure 3 shows the results of evaluating vehicle interior sound. Figure 3 shows the sound inside the vehicle when driving on a rough road.
It shows the 250 Hz level of CT analysis.

In FIG. 3, the transmittance without polyurethane foam was set at 100.

From Figure 3, the thickness of polyurethane foam is H.

It can be seen that when +H8)/H0 is 0.05, the vehicle interior sound is below 90, when it is 0.21 it is approximately 82, and there is no change even when it exceeds 0.35.

As can be seen from FIGS. 2 and 3, road noise is clearly reduced by adding polyurethane foam. In addition, the thickness of polyurethane foam is H+ +)lt
) is 5 to 35% of the maximum inner surface height H8 of the tire, it is found that road noise is effectively reduced.

〔Effect of the invention〕

As explained above, according to the present invention, since the flat member is disposed in the air filling part inside the tire, road noise can be efficiently reduced with almost no change in tire rigidity or tire weight. becomes possible.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram of a cross section in the meridian direction of an example of a tire with a pneumatic rim according to the present invention, Fig. 2 is a diagram showing the relationship between the thickness of polyurethane foam and vibration transmissibility of the tire itself, and Fig. 3 is a diagram showing the relationship between the thickness of polyurethane foam and the vibration transmissibility of the tire itself. It is a relationship diagram with indoor installation. 1... Bead part, 2... Rim, 3... Tread,
4u, 4d: flat plate member, T: ground contact width of tread.

Claims (1)

[Claims] Consisting of an assembly of a tire and a rim, a flat member is disposed on either or both of the inner peripheral wall surface of the tread portion and the outer peripheral surface of the rim between the bead portions, and the inner peripheral wall surface of the tread portion The flat plate member arranged on the peripheral wall surface has a width equivalent to the ground contact width of the tread, and the flat plate member arranged on the outer peripheral surface of the rim between the bead parts has a width equivalent to the linear distance between the bead parts. A tire with a pneumatic rim, characterized in that the sum of the thicknesses of these flat plate members is 5 to 35% of the maximum inner surface height of the tire.