Pneumatic tire

Abstract

A pneumatic tire is disclosed. The pneumatic tire according to the present embodiment may comprise: a carcass disposed to pass a sidewall and reach a bead within a tread; a belt part disposed radially outside the carcass in the tread; a band part disposed radially outside the belt part in the tread; and a noise damper attached to a radially inner surface of the tread, wherein the band part may comprise a first band layer disposed radially outside of the belt part and a second band layer extending from one end of the first band layer to at least a part of the noise damper in the width direction of the tread and disposed radially outside of the first band layer.

Description

pneumatic tires

[0001] The present invention relates to a pneumatic tire, and more particularly, to a pneumatic tire capable of reducing noise generated while a vehicle is running and improving durability.

[0002] Typically, pneumatic tires generate vibration and noise when a vehicle is driven at high speeds due to friction or impact between the tread and the road surface. This noise is amplified within the gas-filled cavity, causing discomfort to drivers and passengers. Consequently, various solutions are being studied to address this tire noise issue.

[0003] Fig. 1 is a drawing showing a cross-section of a conventional pneumatic tire for noise reduction. Referring to Fig. 1, the conventional pneumatic tire for noise reduction includes a carcass (10) extending from the inside of a tread (11) through a sidewall (12) to a bead (13), a belt portion (20) arranged on the radially outer side of the carcass (10) on the inside of the tread (11), a band portion (30) arranged on the radially outer side of the belt portion (20) on the inside of the tread (11), and a noise damper (40) attached to the center of the radially inner side of the tread (11) and extending in the circumferential direction of the tire.

[0004] In such pneumatic tires, the band portion (30) is formed as a single band layer as a whole, and only a portion of both ends in the width direction of the tire is formed as two band layers. In addition, the two band layers provided on both ends of the band portion (30) are provided spaced apart from the noise damper (40) by a preset interval in the width direction of the tire. That is, in such pneumatic tires, there is no overlap between the two band layers of the band portion (30) and the noise damper (40) in the circumferential direction of the tire.

[0005] Accordingly, in such conventional pneumatic tires, when the width of the noise damper (40) is formed to be large, the width of the two band layers provided on both ends of the band portion (30) becomes too narrow, and thus the belt portion (20) cannot be prevented from rising from the carcass (10) due to centrifugal force when the vehicle is driven at high speed, thereby causing a problem in that the durability of the tire is reduced.

[0006] In addition, in order to secure the durability of the tire, a pneumatic tire in which the band portion (30) is formed as two band layers on the radially outer side of the belt portion (20) may cause another problem of reducing the fuel efficiency of the vehicle as the weight of the tire increases significantly.

[0007] The present embodiment seeks to provide a pneumatic tire capable of reducing tire noise amplified within a tire cavity due to friction or impact between a tread and a road surface.

[0008] The present embodiment aims to provide a pneumatic tire that can suppress the rise of a belt portion due to centrifugal force during high-speed driving of a vehicle while minimizing weight increase, and improve the durability and cornering strength of the tire.

[0009] According to one aspect of the present invention, a pneumatic tire may be provided, including a carcass arranged from the inside of a tread through a sidewall to a bead, a belt portion arranged radially outside the carcass from the inside of the tread, a band portion arranged radially outside the belt portion from the inside of the tread, and a noise damper attached to a radially inner surface of the tread, wherein the band portion includes a first band layer arranged radially outside the belt portion, and a second band layer extended from one end of the first band layer to at least a portion of the noise damper in the width direction of the tread and arranged radially outside the first band layer.

[0010] The above band portion may be formed by winding a band fly having a constant width, the first band layer may be formed by winding the band fly at a pitch of 100% to 105% of the band fly width, and the second band layer may be formed by winding the band fly at a pitch of 45% to 90% of the band fly width.

[0011] The second band layer may include a fully overlapping portion in which the band ply is wound at a pitch of 45% to 55% of the band ply width, and a partially overlapping portion in which the band ply is wound at a pitch of 65% to 90% of the band ply width.

[0012] The above-mentioned partial overlapping portion may include a first region extending from the complete overlapping portion in the tire axial direction to one end side of the noise damper, and a second region continuous with the first region and overlapping at least a portion of the noise damper in the tire axial direction from one end side of the noise damper.

[0013] The first region may be provided with a width of 5% to 25% of the width of the belt portion based on the width direction of the tread, and the second region may be provided with a width of 2% to 30% of the width of the belt portion based on the width direction of the tread.

[0014] The above-mentioned full overlapping portion may be provided with a width of 10% to 25% of the tread contact width based on the width direction of the tread, and the above-mentioned partial overlapping portion may be provided with a width of 7% to 40% of the tread contact width based on the width direction of the tread.

[0015] The above belt portion may include a first belt layer arranged radially outside the carcass, and a second belt layer arranged radially outside the first belt layer.

[0016] The above noise damper may be provided with a width of 40% to 70% of the tread contact width based on the width direction of the tread.

[0017] The above noise damper may be formed to extend along the circumferential direction of the tread.

[0018] The above noise damper can be formed by dividing it into equal intervals along the circumferential direction of the tread.

[0019] The pneumatic tire according to the present embodiment can reduce tire noise amplified within the tire cavity due to friction or impact between the tread and the road surface, thereby providing a comfortable driving environment to the driver and passengers.

[0020] The pneumatic tire according to the present embodiment can improve the durability and driving stability of the tire by suppressing injury of the belt portion and improving cornering strength while minimizing weight increase.

[0021] Figure 1 is a drawing showing a cross-section of a conventional pneumatic tire for noise reduction.

[0022] Fig. 2 is a cross-sectional view showing a main part of a pneumatic tire according to one embodiment of the present invention.

[0023] Figure 3 is a cross-sectional view illustrating a pneumatic tire according to one embodiment of the present invention.

[0024] Figure 4 is a cross-sectional view illustrating a pneumatic tire according to one embodiment of the present invention.

[0025] FIG. 5 is a drawing showing a side view of a pneumatic tire according to one embodiment of the present invention.

[0026] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided to sufficiently convey the spirit of the present invention to those skilled in the art. The present invention is not limited to the embodiments presented herein and may be embodied in other forms. To clarify the present invention, the drawings may omit portions irrelevant to the description, and the sizes of components may be slightly exaggerated to facilitate understanding.

[0027] Fig. 2 is a cross-sectional view illustrating a main part of a pneumatic tire according to an embodiment of the present invention, and Figs. 3 and 4 are cross-sectional views illustrating a pneumatic tire according to an embodiment of the present invention, respectively. In addition, Fig. 5 is a drawing illustrating a side view of a pneumatic tire according to an embodiment of the present invention.

[0028] Referring to FIGS. 2 to 5, the pneumatic tire according to the present invention may include a carcass (100), a belt portion (200), a band portion (300), and a noise damper (400).

[0029] The carcass (100) is a cord layer that forms the skeleton of the tire. As shown in FIG. 3, it extends from the tread (110) to both sides, passes through the sidewall (120), and reaches the bead (130). It supports the air pressure inside the tire and the load of the entire vehicle, and can be deformed according to road impact while the vehicle is driving.

[0030] More specifically, the carcass (100) is positioned inside the tire to form the basic shape of the tire and support the load of the vehicle. To this end, the carcass (100) may include multiple layers made of organic fibers and / or inorganic fibers capable of satisfying the strength and flexibility required for the tire.

[0031] Additionally, although not shown, the carcass (100) may include an inner liner layer that is provided radially inwardly of the carcass (100) to protect the internal space of the tire from air and moisture. In addition, the carcass (100) may be provided such that the sidewall (120) and the bead (130) are symmetrical on both sides with respect to the center of the tread (110), as shown in FIG. 3.

[0032] The tread (110) forms the surface where the tire comes into contact with the road surface and provides traction for the vehicle. To this end, the tread (110) may be provided in various shapes and materials to ensure sufficient traction for the tire depending on road conditions. For example, the tread (110) may be provided with a thick rubber layer, and may be made of rubber that is resistant to abrasion and impact to protect the carcass (100), belt portion (200), and band portion (300), and has high wear resistance to extend the driving life of the tire. In addition, the tread (110) may include various patterns of grooves provided on the contact surface to improve grip.

[0033] In addition, the tread contact width (TW) hereinafter refers to the width of the contact surface where the tread (100) comes into contact with the ground in the tire axial direction when a pneumatic tire according to an embodiment of the present invention is assembled on a standard rim and a standard load is applied while being charged with a standard internal pressure. In addition, the width direction of the tread refers to the same direction as the width or axial direction of the tire.

[0034] The sidewall (120) is positioned between the tread (110) and the bead (130) to protect the carcass (100) and enhance ride comfort through flexible flexion and elongation. To this end, the sidewall (120) can be provided in various shapes and materials to ensure sufficient flexibility. Furthermore, various information, such as the tire type, size structure, pattern, manufacturer, and brand name, can be displayed on the sidewall (120).

[0035] A bead (130) is located on the inner surface of the tire and adheres closely to the rim, thereby securing the tire to the vehicle's wheel. To this end, the bead (130) may be provided in various shapes and materials, including a bead wire (not shown), a bead core (not shown), etc., so that the tire can be stably secured to the rim. In addition, the bead (130) may be provided to slightly tighten the rim so that the tire does not come off the rim even when the tire's air pressure rapidly decreases while driving.

[0036] Meanwhile, the belt portion (200) is arranged radially outside the carcass (100) inside the tread (110) to increase the strength of the tread (110) and to protect the carcass (110) by preventing impact received by the tread (110) and cracks generated in the tread (110) from being transmitted to the carcass (100). To this end, the belt portion (200) may include a plurality of belt layers formed by winding cords such as steel, textile, or aramid fiber in the circumferential direction of the tire. In addition, the belt portion (200) may be formed symmetrically on both sides based on the center of the width of the tread (110), as illustrated in FIG. 3.

[0037] More specifically, the belt portion (200) may include a first belt layer (210) arranged radially outside the carcass (100) and a second belt layer (220) arranged radially outside the first belt layer (210). That is, the belt portion (200) may be formed by stacking two belt layers (210, 220). In addition, without being limited thereto, a medium-duty pneumatic tire applied to a relatively heavy vehicle such as a truck or a bus may include a belt portion (200) formed by stacking a plurality of belt layers exceeding two.

[0038] In addition, the first belt layer (210) is formed to be slightly longer than the second belt layer (220), so that the end of the second belt layer (220) can be placed on the first belt layer (210), as illustrated in FIG. 4. In addition, although not illustrated, the first belt layer (210) may be formed to have the same length as the second belt layer (220), so that the end of the first belt layer (210) can be provided at the same position as the end of the second belt layer (220).

[0039] In addition, the width of the belt portion (200) hereinafter refers to the width of the first belt layer (210) having the widest width based on the width direction of the tread (100) among the multiple belt layers (210, 220) provided as described above.

[0040] Meanwhile, the band portion (300) is arranged on the radial outer side of the belt portion (200) inside the tread (110) to prevent the belt portion (200) from being lifted from the carcass (100) by centrifugal force when the vehicle is driven at high speed, thereby improving the durability of the tire. To this end, the band portion (300) may be formed by winding a band ply (301) formed with a constant width of organic fibers such as polyester, nylon, rayon, and aramid at a constant pitch in the circumferential direction of the tire.

[0041] More specifically, the band portion (300) may include a first band layer (310) disposed on the radially outer side of the belt portion (200) and a second band layer (320) disposed on the radially outer side of the first band layer (310) and extending from one end of the first band layer (310) to at least a portion of the noise damper (400) in the axial direction of the tire.

[0042] That is, as illustrated in FIG. 4, the first band layer (310) is disposed entirely on the radially outer side of the second belt (220), and the second band layer (320) is disposed on the radially outer side of the first band layer (310), but may be provided on both sides so as to overlap at least a portion of the noise damper (400) in the axial direction of the tire from one end of the first band layer (310).

[0043] To this end, the first band layer (310) may be formed by winding band plies (301) formed with a constant width as described above in the circumferential direction of the tire at a pitch of 100% to 105% of the width of the band plies (301). That is, as illustrated in FIG. 2, the first band layer (310) may be formed such that the band plies (301) are arranged adjacent to each other in the width direction of the tire to form one layer as a whole, or the band plies (301) may be formed such that the band plies (301) are in close contact with each other in the width direction of the tire to form one layer.

[0044] In addition, the second band layer (320) may be formed by winding the band ply (301) in the circumferential direction of the tire with a pitch of 45% to 90% of the width of the band ply (301). That is, as illustrated in FIG. 2, the second band layer (320) may be formed by forming one more layer on the first band layer (310) by overlapping a portion of the band ply (301) adjacent in the width direction of the tire.

[0045] Accordingly, in the pneumatic tire according to the present invention, the second band layer (320) is not manufactured separately from the first band layer (310) and laminated on the first band layer (310) by means of adhesion or the like, but is formed by winding a band ply (301) of a constant width forming the band portion (300) in the circumferential direction of the tire, and can be manufactured at one time by changing the pitch.

[0046] In addition, in FIG. 2, the end of the first band layer (310) is shown as being long so that it extends beyond the belt portion (200), but this is not limited thereto, and the band portion (300) may be formed to have an overall length equal to or shorter than the belt portion (200) so that the end of the first band layer (310) or the second band layer (320) is placed on the belt portion (200).

[0047] In addition, the second band layer (320) may include a complete overlapping portion (321) provided at a preset distance from one end of the band portion (320) in the tire axial direction to one end of the noise damper (400), and a partial overlapping portion (322) extending from the complete overlapping portion (321) to at least a portion of the noise damper (400) in the tire axial direction.

[0048] Here, the full overlapping portion (321) may be provided with a width of 10% to 25% of the tread (100) contact width based on the width direction of the tread (100). In addition, the partial overlapping portion (322) may be provided with a width of 7% to 40% of the tread (100) contact width based on the width direction of the tread (100).

[0049] In addition, the full overlapping portion (321) can be prepared by winding the band ply (301) around the belt portion (200) at a pitch of 45% to 55% of the width of the band ply (301). In addition, the partial overlapping portion (322) can be prepared by winding the band ply (301) around the belt portion (200) at a pitch of 65% to 90% of the width of the band ply (301).

[0050] That is, as shown in FIG. 2, the fully overlapping portion (321) may be formed by arranging parts of the band fly (301) adjacent to each other to form a second band layer (320), and the partially overlapping portion (322) may be formed by arranging parts of the band fly (301) spaced apart from each other by a certain distance to form a second band layer (320).

[0051] Accordingly, the full overlapping portion (321) is formed to have a higher weight compared to the partial overlapping portion (322), and can sufficiently suppress the two ends of the belt portion (200) from being lifted off the carcass (100) due to centrifugal force when the vehicle is driven at high speed. In particular, since the lifting of the belt portion (200) from the carcass (100) due to centrifugal force when the vehicle is driven at high speed mainly starts from the two ends of the belt portion (200), the lifting of the belt portion (200) from the carcass (100) can be more effectively prevented by the full overlapping portion (321) provided at the two ends of the belt portion (200).

[0052] In addition, the partial overlapping portion (322) is formed to have a lower weight compared to the full overlapping portion (321), so that the second band layer (320) is formed only with the relatively heavy full overlapping portion (321), thereby preventing the overall weight of the band portion (300) from increasing. At this time, the width of the full overlapping portion (321) and the width of the partial overlapping portion (322) may be determined in consideration of the noise and durability characteristics of the pneumatic tire according to the present invention. For example, the partial overlapping portion (322) may be formed on the entire band portion (300) except for the full overlapping portion (321).

[0053] Accordingly, the pneumatic tire according to the present invention can be provided with the second band layer (320) partially overlapping the noise damper (400), thereby minimizing the increase in weight compared to a conventional pneumatic tire for noise reduction, while suppressing the lifting of the belt portion (200) from the carcass (100) due to centrifugal force, and improving cornering stiffness, thereby further improving the durability and driving stability of the tire.

[0054] Meanwhile, the partial overlapping portion (322) may be divided into a first region (322a) extending from the inner end of the complete overlapping portion (321) in the tire axial direction to one end of the noise damper (400), as illustrated in FIG. 2, and a second region (322b) overlapping at least a portion of the noise damper (400) from the first region (322a) in the tire axial direction. Here, the first region (322a) may be provided with a width (w1) of 5% to 25% of the width of the belt portion (200) based on the tire axial direction. In addition, the second region (322b) may be provided with a width (w2) of 2% to 30% of the width of the belt portion (200) based on the tire axial direction.

[0055] The division of the area of ​​the partial overlapping portion (322) and the tire axial length of each area are used to determine the overall length of the partial overlapping portion (322) and at the same time to determine the distance between the complete overlapping portion (321) and the noise damper (400) in the tire axial direction, and can be determined within the above range in consideration of the noise and / or durability characteristics of the pneumatic tire according to the present invention.

[0056] Meanwhile, as illustrated in FIGS. 3 and 4, the noise damper (400) is attached to the radial inner surface of the tread (110) to reduce tire noise amplified within the tire cavity due to friction or impact between the tread (110) and the road surface. To this end, the noise damper (400) may be formed of various materials, including foam rubber, foam synthetic resin, sponge, etc., and in various shapes, including foam, porous structures, etc.

[0057] In addition, the noise damper (400) has its center of gravity positioned on the same line as the center of the tread (110) and the circumferential direction of the tire, thereby balancing the load applied to the tire and maintaining mechanical balance, thereby preventing the tire from being deviated from the tread (110) due to weight eccentricity during high-speed driving.

[0058] In addition, the noise damper (400) is illustrated as having a rectangular cross-section, but is not limited thereto and may be provided in various shapes and sizes depending on the noise reduction performance and the overall shape and specifications of the tire.

[0059] In addition, the noise damper (400) may be formed in a circular ring shape by extending along the circumference of the tread (100). In addition, as illustrated in FIG. 5, the noise damper (400) may be formed in a plurality of equal intervals along the circumference of the tread (100).

[0060] In addition, as illustrated in FIG. 3, the noise damper (400) may be provided with a width (w3) of 40% to 70% of the tread contact width (TW) based on the width direction of the tread (100).

[0061] Accordingly, the pneumatic tire according to the present embodiment can effectively reduce tire noise amplified within the tire cavity due to friction or impact between the tread (110) and the road surface, thereby providing a comfortable driving environment to the driver and passengers.

[0062] Although specific embodiments of the pneumatic tire according to the present invention have been described so far, it is obvious that various modifications are possible within the scope of the present invention.

[0063] Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined not only by the claims described below but also by equivalents of the claims.

[0064] That is, it should be understood that the above-described embodiments are exemplary in all respects and not restrictive, and the scope of the present invention is indicated by the patent registration claims to be described later rather than the detailed description, and all changes or modified forms derived from the meaning and scope of the patent registration claims and their equivalent concepts should be interpreted as being included in the scope of the present invention.

Claims

A carcass arranged from the inside of the tread through the sidewall to the bead; A belt portion arranged radially outside the carcass within the tread; A band portion arranged radially outside the belt portion within the tread; and A noise damper attached to the radial inner surface of the tread; The above band part A first band layer arranged on the radially outer side of the above belt portion, A pneumatic tire comprising a second band layer extending from one end of the first band layer to at least a portion of the noise damper in the width direction of the tread and disposed radially outerward of the first band layer. In the first paragraph, The above band part A band fly is formed by winding and forming a band fly of a certain width, The above first band layer The above band fly is wound with a pitch of 100% to 105% of the band fly width, The above second band layer A pneumatic tire in which the above band ply is wound at a pitch of 45% to 90% of the width of the above band ply. In the second paragraph, The above second band layer A fully overlapping portion in which the above band fly is wound with a pitch of 45% to 55% of the above band fly width, A pneumatic tire including a partially overlapping portion in which the above band ply is wound at a pitch of 65% to 90% of the width of the above band ply. In the third paragraph, The above partial overlapping part A first region extending from the above-mentioned complete overlapping portion to one end of the noise damper in the tire axis direction, A pneumatic tire including a second region that is continuous with the first region and overlaps at least a portion of the noise damper in the tire axial direction from one end side of the noise damper. In paragraph 4, The above first area is It is provided with a width of 5% to 25% of the width of the belt portion based on the width direction of the tread, The above second area is A pneumatic tire provided with a width of 2% to 30% of the width of the belt portion based on the width direction of the tread. In the third paragraph, The above complete overlapping part It is provided with a width of 10% to 25% of the tread contact width based on the width direction of the tread, The above partial overlapping part A pneumatic tire provided with a width of 7% to 40% of the tread contact width based on the width direction of the tread. In the first paragraph, The above belt part A first belt layer arranged on the radially outer side of the above carcass, A pneumatic tire comprising a second belt layer arranged radially outer side of the first belt layer. In the first paragraph, The above noise damper A pneumatic tire provided with a width of 40% to 70% of the tread contact width based on the width direction of the tread. In the first paragraph, The above noise damper A pneumatic tire formed to extend along the circumference of the tread. In the first paragraph, The above noise damper A pneumatic tire in which the treads are divided and formed at equal intervals along the circumference of the tread.

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