KR102310057B1 - sound absorber for tires - Google Patents

Abstract

A disclosed sound absorbing material for a tire comprises: a body in a ring shape, engaged with an inner surface of the tire; a chamber in a ring shape, formed inside and along the body; a plurality of first recessed units formed on one side of the body at regular intervals; and a plurality of second recessed units formed on the other side of the body at regular intervals not to face the first recessed units. The sound absorbing material for a tire reduces noise by increasing a surface area while reducing the weight of the sound absorbing material, and at the same time, obtains uniformity of the tire with the sound absorbing material attached.

Description

Sound absorber for tires

The present invention relates to a sound absorbing material for a tire, and more particularly, to a sound absorbing material coupled to the inside of a tire to reduce noise generated by the tire.

In general, pneumatic tires have a support function that supports the entire load of the vehicle, a power transmission function that transmits the driving force and braking force of the vehicle to the road surface, a shock mitigation function that alleviates external shocks caused by irregular road surfaces, and the progress of the vehicle. It is equipped with various position change functions, etc. to change the position according to the direction.

A typical structure of such a pneumatic tire includes a tread, which is a thick rubber layer in direct contact with the road surface; Shoulder (Shoulder) constituting the shoulder of the tire with the thickest thickness; A side wall on the side of the tire that improves the riding comfort through flexible flexing and extending motion and displays the type, size, manufacturer, etc. of the tire; A bead that surrounds the end of the cord paper so that the tire is mounted on the rim (Bead); Carcass made of tire cord paper, that is, a body ply as a part that forms the skeleton of the tire and withstands air pressure and load or impact inside the tire, and a layer inserted inside the tread and the body ply. a belt layer that relieves the impact of the tread and prevents cracks or trauma of the tread from reaching the body ply directly; A rubber layer provided inside the body ply is made of an inner liner to prevent air leakage.

And the pneumatic tire is provided with a rim (Rim) is mounted to surround the outer surface of the bead portion.

Here, when the rim is mounted on the bead, a cavity is formed inside the tire, and when the cavity is filled with compressed air, the tire absorbs an impact from the ground and supports the vehicle body.

However, since a cavity is formed inside the tire, a space is provided for sound waves to resonate while driving a vehicle to generate cavity resonance due to vibration of air, and the cavity resonance is transmitted to the outside and inside of the vehicle. As a result, it not only causes dissatisfaction with the noise to drivers or passengers, but also causes noise pollution in the external environment.

In particular, road noise of a pneumatic tire is a sound wave in the range of 50 to 400 Hz generated from a tire traveling on a road, and the main cause of the road noise is resonance vibration of air generated in the tire cavity.

The cavity resonance sound is generated when the tire tread vibrates due to the unevenness of the road surface, and the vibration vibrates the air inside the tire. The frequency of the cavity resonance sound is known to be around 200 to 250 Hz, and it is important to reduce the noise level in the frequency band to reduce tire noise.

As a method of reducing noise caused by the cavity resonance sound phenomenon, a method of absorbing vibration and noise by attaching a sound absorbing material to the inside of a tire has been recently proposed. It is common to attach a sound absorbing material to the bottom surface of the tire tread, and there are cases in which the mounting position of the sound absorbing material is changed in consideration of the sidewall's flexing/extending motion.

Here, since the geometric shape of the sound-absorbing damper in addition to the material properties of the sound-absorbing damper has a great influence on effective absorption of the cavity resonance sound, the need for the development of an improved sound-absorbing material shape to further improve the sound-absorbing performance has emerged.

Korean Patent Application Laid-Open No. 10-2010-0005511 'A low-noise pneumatic tire with a sound-absorbing damper' has a wedge-shaped sound-absorbing channel made of a plurality of sound-absorbing materials, and the wedge-shaped sound-absorbing channels are connected to each other by crossing them at an angle of 90 degrees. Disclosed is a pneumatic tire characterized in that it has a structure.

An object of the present invention is to provide a sound absorbing material for a tire with improved uniformity.

The object includes a ring-shaped body coupled to the inner surface of the tire; A ring-shaped chamber formed therein along the body; A plurality of first depressions formed at equal intervals on one side of the body; and a sound-absorbing material for a tire that may include a plurality of second depressions formed at equal intervals so as not to face the first depressions on the other side of the body.

In addition, the above object, the body, the bottom portion in contact with the inner surface of the tire; a side wall portion coupled to both sides of the bottom portion; and a cover portion coupled to the sidewall portion, wherein the body is made of a flexible material and can be achieved by a sound absorbing material for a tire that can be bent according to the deformation of the tire.

In addition, the above object can be achieved by a sound absorbing material for a tire in which the width of the bottom portion of the body is greater than the width of the cover portion.

In addition, the above object can be achieved by a sound absorbing material for a tire that is made of a hard material and can maintain its initial shape even when the air pressure inside the tire is low.

In addition, the above object can be achieved by a sound absorbing material for a tire in which the body is formed with one or more channels connecting the chamber and the outside of the body at predetermined intervals.

In addition, the above object can be achieved by a sound-absorbing material for a tire in which the body is formed with a partition wall dividing the chamber at predetermined intervals.

In addition, the above object can be achieved by a sound absorbing material for a tire in which a passage connecting chambers adjacent to the bulkhead can be formed in the body.

In addition, the above object may be achieved by a sound absorbing material for a tire in which one or more partition walls may be formed parallel to the rotational direction of the tire.

In addition, the above object may be achieved by a sound absorbing material for a tire in which a plurality of first protrusions for dispersing noise may be formed on the outer surface of the body.

In addition, the above object may be achieved by a sound absorbing material for a tire in which a plurality of second protrusions for dispersing noise may be formed on the inner surface of the body.

According to the sound-absorbing material for a tire according to the present invention, a ring-shaped body coupled to the inner surface of the tire; A ring-shaped chamber formed therein along the body; A plurality of first depressions formed at equal intervals on one side of the body; and a plurality of second depressions formed at equal intervals so as not to face the first depressions on the other side of the body, thereby increasing the surface area while reducing the weight of the sound-absorbing material to obtain a noise reduction effect and at the same time attaching the sound-absorbing material The uniformity of the tire can be obtained.

In addition, according to the sound-absorbing material for a tire according to the present invention, the body includes: a bottom portion in contact with the inner surface of the tire; a side wall portion coupled to both sides of the bottom portion; and a cover part coupled to the side wall part, wherein the body is made of a flexible material and can be bent according to the deformation of the tire, thereby preventing damage to the sound absorbing material on an uneven road surface.

In addition, according to the sound absorbing material for a tire according to the present invention, since the width of the bottom portion of the body may be greater than the width of the cover portion, the area where the sound absorbing material is attached to the tire may be increased.

In addition, according to the sound absorbing material for a tire according to the present invention, since the cover part is made of a hard material and can maintain its initial shape even when the air pressure inside the tire is low, the tire can maintain its shape even when the pressure inside the tire is lowered due to damage of the tire. have.

In addition, according to the sound absorbing material for a tire according to the present invention, since one or more channels connecting the chamber and the outside of the body may be formed in the body at predetermined intervals, the chamber of the sound absorbing material may serve as a resonator.

In addition, according to the sound absorbing material for a tire according to the present invention, since the body may have partition walls dividing the chamber at predetermined intervals, the chamber may serve as a plurality of resonators while increasing the rigidity of the sound absorbing material.

In addition, according to the sound absorbing material for a tire according to the present invention, the body can be formed with a passage connecting the chambers adjacent to the barrier rib, so that the barrier rib can be easily deformed while securing the rigidity of the sound absorbing material. A plurality of chambers serving as a resonator can be connected to each other to reduce noise while at the same time preventing the breakage of the device.

In addition, according to the sound-absorbing material for a tire according to the present invention, one or more partition walls may be formed parallel to the rotational direction of the tire, so that the chamber of the sound-absorbing material can maintain its shape even when the pressure inside the tire is lowered.

In addition, according to the sound absorbing material for a tire according to the present invention, since a plurality of first protrusions for dispersing noise may be formed on the outer surface of the body, it is possible to reduce noise on the outer surface of the sound absorbing material.

In addition, according to the sound absorbing material for a tire according to the present invention, since a plurality of second protrusions for dispersing the noise may be formed on the inner surface of the body, it is possible to more effectively reduce the noise in the sound absorbing material chamber.

1 is a perspective view of a sound absorbing material for a tire according to an embodiment of the present invention.
2 is a front view of a portion of a sound absorbing material for a tire according to an embodiment of the present invention.
3 is a cross-sectional view of a portion taken along line XX′ in FIG. 1 .
FIG. 4 is a cross-sectional view of a portion taken along line YY′ in FIG. 2 .
Figure 5 shows that the projection is formed on the body in Figure 3;
6 is a perspective view of a portion of a tire having a sound absorbing material for a tire installed therein according to an embodiment of the present invention.
7 is a front view of a portion of a sound absorbing material for a tire according to another embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

However, in describing the present invention, descriptions of already known functions or configurations will be omitted in order to clarify the gist of the present invention.

The X, Y, and Z axes shown in the drawings are arbitrarily set for convenience of explanation, not for the purpose of limiting rights. , and the Z axis is defined as indicating the up and down directions.

Each direction described below is based thereon, except where otherwise specifically limited.

Top (top), bottom (bottom), left and right (side or lateral), front (front, front), back (back, back), etc., which refer to directions in the description and claims of the invention, are not intended to limit the right. For the convenience of description, the relative positions between the drawings and the components are determined as a reference, and each direction described below is based on this, except when otherwise specifically limited.

The Helmholtz resonance principle applied to the present invention will be schematically described.

In general, a Helmholtz resonator consists of a relatively small opening and a hermetic cavity, and the mass of air in the neck and the volume elasticity of the cavity form a single resonant mechanism.

That is, in the Helmholtz resonator, the air in the neck acts as a mass and the air inside acts as a spring to cause resonance, and by changing the structure of the resonator, the resonance frequency can be changed.

The Helmholtz resonance frequency is expressed in Equation 1 below.

f: Helmholtz resonance frequency

C: the speed of sound in the fluid

S: cross-sectional area of fluid inlet

L: length of fluid inlet

V: volume of resonant space

1 to 6,

The sound absorbing material for a tire includes a ring-shaped body 30 coupled to the inner surface of the tire 10; A ring-shaped chamber 40 formed therein along the body 30; A plurality of first depressions 50 formed at equal intervals on one side of the body 30; and a plurality of second depressions 60 formed at equal intervals on the other side of the body 30 so as not to face the first depressions 50 .

1 to 4 , the body 30 is a part corresponding to the skeleton constituting the sound absorbing material 20 , and the ring-shaped body 30 has an outer circumference coupled to the inner liner 15 inside the tire 10 . can be

The body 30 may be made of a synthetic resin such as polypropylene or polyurethane or rubber to absorb the noise of the tire 10 .

The body 30 is made of a flexible material and can be bent according to the deformation of the tire 10 .

The body 30 may be made of a porous material (porous foam).

In the porous material, minute holes formed in the material may serve as a passage 36 through which noise is introduced into the chamber 40 .

The body 30 includes a bottom part 31 in contact with the inner surface of the tire 10 , a side wall part 32 coupled to both sides of the bottom part 31 , and a cover part 33 coupled to the side wall part 32 . may include.

When viewed based on the chamber 40 formed along the longitudinal interior of the body 30 , the bottom part 31 is located below the chamber 40 , and the side wall part 32 is located on both sides of the chamber 40 . and the cover part 33 is positioned above the chamber 40 .

In the body 30 , the width W1 of the bottom part 31 is greater than the width W2 of the cover part 33 to increase the area attached to the inner surface of the tire 10 .

The body 30 may include any one or more of the bottom part 31 , the side wall part 32 , and the cover part 33 using a flexible material.

The flexible material may be selected from plastics having a property of being deformable together with the tire 10 when the tire 10 is deformed due to an uneven road surface or the like.

The body 30 may include any one or more of the bottom part 31 , the side wall part 32 , and the cover part 33 using a hard material.

The hard material may be selected from plastics having characteristics that can withstand the tire 10 from being crushed when the pressure inside the tire 10 is lowered due to a puncture or the like.

The body 30 may form one or more of the bottom part 31, the side wall part 32, and the cover part 33 with a flexible material, and may form at least one of the other with a hard material.

The body 30 may form the bottom part 31 and the side wall part 32 of a flexible material, and the cover part 33 may be formed of a hard material.

When the bottom part 31 and the side wall part 32 are formed of a flexible material, when the tire 10 is deformed due to an uneven road surface, the body 30 is deformed together with the tire 10 to prevent damage. have.

When the cover part 33 is formed of a hard material, when the pressure inside the tire 10 is lowered due to a puncture or the like, the tire 10 can travel a predetermined distance without being crushed, thereby preventing a safety accident.

1 to 4 , the body 30 may have a zigzag shape depending on the shape of the first recessed part 50 and the second recessed part 60 .

The first recessed part 50 is formed so that one side of the ring-shaped body 30 is recessed inwardly.

The second recessed part 60 is formed so that the other side of the ring-shaped body 30 is recessed inwardly.

As shown in FIG. 2 , the second recessed part 60 and the first recessed part 50 may be formed to form a rectangular shape inward from the side of the body 30 .

The second recessed part 60 is located opposite to the first recessed part 50 .

The second recessed parts 60 are formed in the body 30 opposite to the first recessed part 50 at a center position of the adjacent first recessed parts 50 spaced apart from each other by a predetermined interval.

The first recessed portion 50 is formed in plurality at equal intervals on one side of the ring-shaped body 30 .

The second recessed part 60 is formed in plurality at the same interval so as not to face the first recessed part 50 on the other side of the annular body 30 .

When the first recessed part 50 and the second recessed part 60 are formed, the surface area can be increased compared to other sound absorbing materials having the same width.

Since the first recessed part 50 and the second recessed part 60 are formed in the body 30 at equal intervals, uniformity of the tire 10 may be obtained.

As shown in FIG. 7 , the second recessed part 60 and the first recessed part 50 may be formed to form a triangular shape inward from the side surface of the body 30 .

The second recessed part 60 and the first recessed part 50 may be formed in various shapes as needed.

Referring to FIGS. 3 to 4 , the chamber 40 is a space formed long inside the body 30 along the longitudinal direction, and may help lighten the sound absorbing material 20 and increase the surface area of the sound absorbing material at the same time.

The chamber 40 may have a zigzag shape along the zigzag body 30 .

One or more channels 35 connecting the chamber 40 and the outside of the body 30 may be formed in the body 30 at predetermined intervals.

The channel 35 may be formed in the side wall portion 32 and/or the cover portion 33 of the body 30 .

The channel 35 is a space through which noise from the outside of the sound absorbing material 20 is introduced into the chamber 40 .

When the channel 35 is formed, the chamber 40 may be a space in which noise introduced from the outside is reduced.

The channel 35 may change the cross-sectional area and length according to the frequency of noise desired to be reduced.

The channel 35 may have an outer cross-sectional area larger than an inner cross-sectional area to increase an inlet through which noise is introduced.

The channel 35 may substantially expand the volume of the resonance space by forming an outer cross-sectional area smaller than an inner cross-sectional area.

One or more pairs of channels 35 are formed to face each other on the side wall 32 of the body 30 to secure more paths through which noise is introduced.

The channel 35 may be formed in the side wall portion 32 of the body 30 constituting the first depression 50 and the second depression 60 .

The chamber 40 may reduce noise introduced through the channel 35 using the Helmholtz resonance principle.

The body 30 may have a plurality of partition walls 34 dividing the chamber 40 at predetermined intervals.

The chamber 40 may be divided into several by partition walls 34 formed at predetermined intervals to serve as a plurality of resonators.

The partition walls 34 are formed at predetermined intervals inside the body 30 to separate the chambers 40 and at the same time help to secure the rigidity of the sound insulation material.

One or more partition walls 34 may be formed parallel to the rotation direction of the tire 10 .

When the partition wall 34 is formed parallel to the virtual disk positioned at the center of the body 30 , the chamber 40 of the sound damping material may maintain its shape even if the pressure inside the tire 10 is low.

The partition wall 34 may be formed to overlap the virtual disk located at the center of the body 30 .

The partition wall 34 may be formed so as not to overlap the virtual disk located at the center of the body 30 .

The partition wall 34 may be formed to face the virtual disk located at the center of the body 30 .

When the first recessed part 50 and the second recessed part 60 are formed in a quadrangular shape, a plurality of partition walls 34 may be formed to face each other.

In the body 30 , a passage 36 connecting the chamber 40 adjacent to the partition wall 34 may be formed.

Passages 36 connect neighboring chambers 40 separated by partition walls 34 .

The noise introduced into any one chamber 40 may be reduced by moving to the neighboring chamber 40 through the passage 36 .

When the tire 10 is deformed due to an uneven road surface, etc., the passage 36 allows the partition wall 34 to be easily deformed, thereby preventing the sound absorbing material 20 from being damaged due to a sudden change in volume of the chamber 40. have.

The chamber 40 may be coated with a sound-absorbing layer on the surface.

The sound absorbing layer may absorb the noise introduced into the chamber 40 .

For the sound-absorbing layer, different materials can be selected according to the frequency of the noise desired to be absorbed.

The channel 35 may be coated with a sound absorbing layer coated on the chamber 40 .

Referring to FIG. 5 , a plurality of first protrusions 37 for dispersing noise may be formed on the outer surface of the body 30 .

The body 30 may have a plurality of second protrusions 38 formed on its inner surface for dispersing noise.

The first protrusion 37 and the second protrusion 38 may refract, reflect, or disperse a wave of noise.

The first protrusion 37 and the second protrusion 38 may be formed differently in shape, size, arrangement, and number according to the frequency of noise desired to be absorbed.

The first protrusion 37 and the second protrusion 38 may be coated with a sound-absorbing layer on the surface.

The sound-absorbing layer may absorb noise hitting the first protrusion 37 or the second protrusion 38 .

For the sound-absorbing layer, different materials can be selected according to the frequency of the noise desired to be absorbed.

In the foregoing, specific embodiments of the present invention have been described and shown, but it is common knowledge in the art that the present invention is not limited to the described embodiments, and that various modifications and variations can be made without departing from the spirit and scope of the present invention. It is self-evident to those who have

Therefore, such modifications or variations should not be individually understood from the technical spirit or viewpoint of the present invention, and it should be said that the modified embodiments belong to the claims of the present invention.

10: tire
11: tread
12: sidewall
13: shoulder
14: bead
15: inner liner
20: sound absorbing material
30: body
31: bottom
32: side wall part
33: cover part
34: bulkhead
35: channel
36: passage
37: first projection
38: second projection
40: chamber
50: first depression
60: second depression

Claims (10)

a ring-shaped body coupled to the inner surface of the tire;
A ring-shaped chamber formed therein along the body;
a plurality of first depressions formed at equal intervals on one side of the body; and
The sound absorbing material for a tire, characterized in that it includes a plurality of second depressions formed at equal intervals so as not to face the first depressions on the other side of the body. According to claim 1,
The body is
a bottom portion abutting the inner surface of the tire;
side wall portions coupled to both sides of the bottom portion; and
It includes a cover portion coupled to the side wall portion,
The sound absorbing material for a tire, characterized in that the body is made of a flexible material and can be bent according to the deformation of the tire. 3. The method of claim 2,
The body is a sound absorbing material for a tire, characterized in that the width of the bottom portion is greater than the width of the cover portion. 4. The method of claim 3,
The sound absorbing material for a tire, characterized in that the cover part is made of a hard material and can maintain its initial shape even when the air pressure inside the tire is lowered. 5. The method according to any one of claims 1 to 4,
In the body, at least one channel connecting the chamber and the outside of the body is formed at predetermined intervals. 6. The method of claim 5,
The body has a sound absorbing material for tires, characterized in that the partition wall dividing the chamber is formed at predetermined intervals. 7. The method of claim 6,
The body has a sound absorbing material for tires, characterized in that the passage connecting the chambers adjacent to the partition wall is formed. 8. The method of claim 7,
The sound absorbing material for a tire, characterized in that at least one partition wall is formed parallel to the rotation direction of the tire. 9. The method of claim 8,
The body is a sound absorbing material for tires, characterized in that the plurality of first projections for dispersing the noise are formed on the outer surface. 10. The method of claim 9,
The body is a sound absorbing material for tires, characterized in that the plurality of second projections for dispersing the noise are formed on the inner surface.

Images