JP2004306729A - Noise restraint tire side cover - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a noise restraint tire side cover capable of directly restraining noise from a tire without need for modifying in the tire. <P>SOLUTION: The noise restraint tire side cover 1 comprises a supporting member 3a fitted on a wheel 2 of an assembly consisting of the tire/wheel and a vibration control member P fixed at a mounting portion M of a plate-like body B, and abuts the plate-like body B on at least maximum tire width A of the tire T of the assembly in a ground-side. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a noise suppression tire side cover, and more particularly, to a noise suppression tire side cover capable of directly reducing noise generated from a tire while an automobile is running.
[0002]
[Prior art]
As part of recent efforts for environmental protection, there is an increasing demand for reduction of tire noise as a measure to reduce external noise generated when a vehicle travels.
[0003]
Conventionally, as a method of reducing tire noise, for example, changing the configuration of a tread pattern of a tire, or changing the internal structure or contour of the tire has been conventionally performed. However, these methods may adversely affect various performances other than the noise of the tire, and there is a limit as a noise reduction method.
[0004]
Under such circumstances, as a method of reducing tire noise without making any changes to the tire, the initial purpose is to cut off the noise emitted from the tire to the outside during driving by the tire cover arranged outside the wheel. Some proposals for achieving the above have appeared (for example, see Patent Document 1).
[0005]
[Patent Document 1]
JP 2001-294003 A (pages 1-5, FIGS. 1-5)
[0006]
[Problems to be solved by the invention]
However, these tire covers are arranged so as to be separated from the tires and cover the outer surface of the tires, and the noise emitted from the tires during running is intended to be blocked by the tire covers. It does not suppress. As a result, most of the noise is reflected on the inner surface of the tire cover or passes between the outer surface of the tire and the tire cover and leaks to the outside. I didn't.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a noise suppression tire side cover capable of solving the conventional problems and directly suppressing noise generated from the tire without changing the tire.
[0008]
[Means for Solving the Problems]
The present inventor has applied a damping material to the sidewall portion of the tire to determine from which position of the sidewall portion the noise generated is large, and how much the noise reduction effect can be obtained by attaching the damping material. As a result of various studies on such factors, it was found that the largest noise was generated near the grounding part of the side wall part, and that sufficient noise reduction could be obtained by simply suppressing the vibration of the side wall part near the grounding part. I found it. In addition, the noise level is reduced by 2 to 3 dB (A) due to the attachment of the vibration damping material both during the steady running of the tire and during the coasting, and the decreasing tendency is caused by the vehicle speed during the steady running of the tire. Found that it was not much affected.
[0009]
The fact that the noise level is 2 to 3 dB (A) means that the noise energy corresponds to about 50%. Therefore, the ratio of the tire noise radiated by the vibration of the sidewall surface as the noise is about 50%. %. The present invention has been made based on the above findings.
[0010]
Based on such knowledge, the present invention provides a tire side cover having the following configuration. That is, the noise suppression tire side cover of the present invention includes a support member mounted on a wheel of a tire / wheel assembly, and a plate member made of a damping material fixed to the support member. The body is configured to abut against at least the maximum width of the tire on the grounding side of the tire of the assembly.
[0011]
As described above, the plate-shaped body (damping material) of the tire side cover including the supporting member mounted on the wheel and the plate-shaped body made of the vibration damping material fixed to the supporting member is attached to the tire / wheel assembly. The tire at least touches the maximum width of the tire on the ground contact side, so the vibration at the tire maximum width position near the ground contact part, which is the largest cause of tire noise, is directly suppressed, thereby reducing the noise generated from the tire. It can be suppressed effectively.
[0012]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings. Components common to the drawings are denoted by the same reference numerals, and redundant description will be omitted.
[0013]
FIG. 1 shows a first embodiment in which the tire side cover of the present invention is formed in a ring shape. FIG. 1A is a cross-sectional view of the tire / wheel assembly when the tire is running, and FIG. FIG. 2 is a half side view of the tire side cover of FIG.
[0014]
The tire side cover 1 includes a support member 3a detachably attached to the wheel 2, and a plate-shaped body B of a vibration damping material attached to the support member 3a. The outer diameter D of the plate-shaped body B is larger than twice the radial distance R1 from the tire axis O on the grounding center line L perpendicular to the road surface when the tire T is grounded to the tire maximum width position A, and The radial distance R2 from the tire axis O to the road surface G is smaller than twice the radial distance R2, and the inner diameter Q is twice the radial distance R1 from the tire axis O on the grounding center line L to the tire maximum width position A. It is formed in a ring shape to be smaller.
[0015]
On the other hand, the support member 3a is composed of a plurality of members extending radially from the center of the wheel 2, and has a mounting portion M for the plate-shaped body B at the outer end. At the inner end, a mounting member N for the ring-shaped wheel 2 is provided. The plate-shaped member B is detachably attached to the center cap 2a of the wheel 2 by an attachment member N outside the sidewall portion S of the tire T. The mounting structure between the mounting member N and the center cap 2a is not particularly limited, but is made by general-purpose fixing means such as a bolt and a nut.
[0016]
When the tire side cover 1 is mounted on the center cap 2a of the wheel 2 as described above, the maximum width portion of the tire sidewall portion S which bulges outward in a state where the tire T is crushed is a plate-like body B. The mounting is performed so as to be in a contact pressure state. In the state where the plate-shaped body B and the tire maximum width portion are in contact with each other, it is preferable that the tire is filled with a normal internal pressure and the contact pressure is 5 N or more under a state where a normal load is applied.
[0017]
As described above, in the tire / wheel assembly to which the tire side cover 1 is attached, when the tire T is in contact with the ground, the vibration at the maximum width position A of the sidewall portion S is directly controlled by the damping material P of the plate-shaped body B. By shaking, the noise generated from the tire can be reduced.
[0018]
The material of the vibration damping material P is not particularly limited as long as it has a property of damping vibration. Preferably, a polymer material such as rubber or plastic is used as a base polymer to increase the vibration damping performance. For this purpose, a layered inorganic substance such as mica or graphite, or a needle-shaped inorganic substance such as zonolite or potassium titanate is filled as a damping filler. Then, the loss coefficient is preferably set to 0.1 or more, most preferably 0.2 or more in a region of a noise level of 500 to 2000 Hz which occupies most of the outside noise generated from the tire.
[0019]
FIGS. 2A and 2B show a second embodiment of the tire / wheel assembly and the tire side cover when the tire side cover of the present invention is formed in a ring shape. This embodiment differs from the first embodiment in that the support member 3b is detachably attached to the rim 4 of the wheel 2.
[0020]
FIGS. 3A and 3B show a third embodiment of the tire / wheel assembly and the tire side cover when the tire side cover of the present invention is formed in a ring shape. This embodiment is different from the first and second embodiments in that the support member 3c is attached to the cover 2b of the wheel 2 via the elastic member 5, and the biasing force of the elastic member 5 toward the tire T is provided. Thus, the entire ring-shaped plate B is brought into contact with the entirety of the maximum width of the tire T. The mounting structure of the elastic member 5 is not particularly limited, but it is preferable that the elastic member 5 is fixed to one of the cover 2b and the support member 3c and the other is detachable.
[0021]
The elastic member 5 is made of an elastic body such as a spring or rubber, and makes contact with the plate-shaped body B so as to constantly urge the entire width of the sidewall portion S at the tire maximum width A position when the tire T is in contact with the ground. . Then, by appropriately selecting the biasing force of the elastic member 5, the contact pressure of the plate-shaped body B against the sidewall portion S becomes 5N or more under a state where the tire is filled with a regular internal pressure and a regular load is applied. It is preferable to do so. Thereby, the vibration damping effect of the sidewall portion S near the ground contact portion is further ensured.
[0022]
It should be noted that the same function as the elastic member 5 described above is provided between the cap 2a of the wheel 2 and the mounting member N in the first embodiment described above, and between the rim 4 and the mounting member N in the second embodiment. A member that causes the plate-shaped body B to contact the side wall S at the maximum width position A can be interposed. Further, the mounting structure of the tire side cover 1 to the tire T is not limited to the above embodiment.
[0023]
In the above-described embodiment, the case where the tire side cover 1 is formed in a ring shape has been described. However, the tire side cover 1 of the present invention is configured such that at least the plate-shaped body B has the tire maximum width position A of the sidewall S portion on the road surface G side. It is not always necessary to make the ring shape. For example, on the driven wheel side where the axle does not rotate, the plate-shaped body B may have a local shape facing the sidewall S portion on the tire ground contact side.
[0024]
As described above, the tire side cover 1 of the present invention not only reduces the outside noise generated by the tire T, but also contributes to the reduction of the vehicle interior noise caused by air propagation, and further reduces the tire noise. It is suitably used when only noise generated from the vehicle due to the reduction is measured.
[0025]
【The invention's effect】
As described above, the tire side cover according to the present invention includes a tire side cover including a support member mounted on a wheel and a plate-shaped body made of a vibration damping material fixed to the support member. Since it is configured to contact at least the maximum width of the ground contact side tire, the side wall portion at the tire maximum width position near the ground contact portion comes into contact with the plate-shaped body constituting the tire side cover during traveling, so that the vicinity of the ground contact portion is reduced. The vibration damping material directly suppresses the generation of the vibration of the sidewall portion, thereby suppressing the noise generated from the tire.
[Brief description of the drawings]
1A and 1B show a first embodiment of a tire side cover and an assembly of the tire and the tire according to the present invention, wherein FIG. 1A is a cross-sectional view of the assembly of the tire side cover and the tire when the tire is running, and FIG. FIG. 3 is a half side view of a tire side cover.
FIGS. 2A and 2B show a second embodiment of a tire side cover and an assembly of the tire and the tire according to the present invention, wherein FIG. 2A is a sectional view corresponding to FIG. 1A, and FIG. It is a half side view corresponding to FIG.
3A and 3B show a third embodiment of a tire side cover and an assembly of the tire and the tire according to the present invention, wherein FIG. 3A is a sectional view corresponding to FIG. 1A, and FIG. It is a half side view corresponding to FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Tire side cover 2 Wheel 3a, 3b, 3c Support member 4 Rim 5 Elastic member A Tire maximum width position B Plate P Damping material S Side wall O Tire axis G Road surface

Claims (5)

A support member mounted on a wheel of the tire / wheel assembly, and a plate-like body made of a vibration damping material fixed to the support member; A tire side cover for noise suppression that is configured to come into contact with a large area. The noise suppression tire side cover according to claim 1, wherein a loss coefficient of the vibration damping material at 500 to 2000 Hz is 0.1 or more. The tire side cover for noise suppression according to claim 1 or 2, wherein the plate-like body is formed in a ring shape concentric with the tire axis. The tire side cover for noise suppression according to any one of claims 1 to 3, wherein a contact pressure at which the plate-shaped member contacts the maximum width of the tire on the tire ground side is 5N or more. A tire / wheel assembly equipped with the noise suppression tire side cover according to any one of claims 1 to 4.

Images