Patent Description:
There are tires with multiple circumferential main grooves on a tread surface (for example, Patent Literature (PTL) <NUM>). Attention is also drawn to the disclosure of <CIT>.

This application claims priority to <CIT> and <CIT>, filed on May <NUM>, <NUM>.

Conventional tires as described above generally have deep circumferential main grooves and, thus thick tread rubber. This is undesirable from the viewpoint of reduction in tire weight and rolling resistance.

The inventors of the present invention have newly noticed that when the groove depths of the circumferential main grooves are made shallower and thus the thickness of the tread rubber is made thinner, noise tends to increase, though reduction in tire weight and rolling resistance can be expected, and achieved the present invention.

It would be helpful to provide a tire in which increase in noise can be suppressed, while the groove depths of circumferential main grooves are made shallow.

A tire according to the present invention is a tire including a first circumferential main groove and a second circumferential main groove in a tread surface, wherein.

According to the present invention, it is possible to provide a tire in which increase in noise can be suppressed, while the groove depths of circumferential main grooves are made shallow.

A tire according to the present invention can be used as any type of pneumatic tire, but is suitably used as a pneumatic tire for passenger vehicles.

Embodiments of the tire according to the present invention will be exemplarily described below with reference to the drawings. In each of the drawings, the same reference numerals refer to common components.

A tire according to each example described in this specification includes a tread portion <NUM> (<FIG>), a pair of shoulder portions (not illustrated) extending inward in a tire radial direction from both ends of the tread portion <NUM> in a tire width direction, and a pair of bead portions (not illustrated) connected inward in the tire radial direction from the pair of shoulder portions.

The tire according to each example described in this specification may have any internal configuration. The tire according to each example described in this specification may, for example, include a pair of bead cores (not illustrated) provided at the pair of bead portions, a pair of bead fillers (not illustrated) located outside the bead cores in the tire radial direction, a carcass <NUM> (<FIG>), a belt <NUM> (<FIG>), and tread rubber <NUM> (<FIG>). The carcass <NUM> extends in a toroidal shape between the pair of bead cores. The carcass <NUM> includes at least one layer (one layer in the example of the drawing) of carcass ply. The carcass ply of the carcass <NUM> can, for example, be constituted of cords made of steel, organic fibers, or the like coated with rubber. The carcass <NUM> can, for example, include a body portion extending in a toroidal shape between the pair of bead cores, and a pair of turn-up portions turned up outward in the tire width direction around the bead cores from an innermost end of the body portion in the tire radial direction at each of both sides relative to a tire equatorial plane CL. The belt <NUM> is positioned, in the tread portion <NUM>, outside in the tire radial direction relative to a crown region of the carcass <NUM> (<FIG>). The belt <NUM> is constituted of at least one belt layer <NUM> (two layers in the example of the drawing). The belt layer <NUM> can be, for example, constituted of cords made of steel, organic fibers, or the like covered by rubber. The tread rubber <NUM> is disposed outside the belt <NUM> in the tire radial direction.

A tire according to an embodiment of the present invention will be described with reference to <FIG>.

<FIG> is a development view of a tread surface <NUM> of the tire according to the embodiment of the present invention, as developed on a flat surface. <FIG> is an enlarged view of a part of <FIG>. <FIG> is a cross-sectional view in a tire width direction, illustrating a portion of the tire of <FIG> in cross-section along the line A-A of <FIG>. <FIG> is a perspective view illustrating a part of the tire of <FIG> with enlargement.

The tire according to an example of <FIG> is a tire whose mounting direction to a vehicle is specified. In <FIG>, the direction of the arrow OUT indicates a direction of outside (hereinafter referred to as "vehicle-mounted outside") in a vehicle width direction when the tire is mounted on the vehicle. The direction of the arrow IN indicates a direction of inside (hereinafter referred to as "vehicle-mounted inside") in the vehicle width direction when the tire is mounted on the vehicle. In the tread surface <NUM> of this tire, a tread pattern that is asymmetrical with respect to a tire equatorial plane CL is provided.

However, the tire according to each example described in this specification may be a tire whose mounting direction to a vehicle is not specified. A tread pattern of the tire according to each example described in this specification may be asymmetrical with respect to a tire equatorial plane CL or symmetrical with respect to the tire equatorial plane CL.

For convenience, the upper side of <FIG> is referred to as "first tire circumferential side (CD1)" and the lower side of <FIG> as "second tire circumferential side (CD2)" in this specification.

In this specification, "tread surface (<NUM>)" means an outer circumferential surface over an entire circumference of the tire that comes into contact with a road surface when the tire mounted on a rim and filled with a specified internal pressure is rolled under a maximum load.

In this specification, "ground contact edge (TE1, TE2)" refers to an end of the tread surface (<NUM>) in the tire width direction.

In this specification, "rim" means a standard rim (Measuring Rim in ETRTO's STANDARDS MANUAL and Design Rim in TRA's YEAR BOOK) in an applicable size as described in or to be described in an industrial standard valid for regions where tires are produced and used, such as JATMA YEAR BOOK of the JATMA (The Japan Automobile Tyre Manufacturers Association, Inc. ) in Japan, STANDARDS MANUAL of the ETRTO (The European Tyre and Rim Technical Organisation) in Europe, YEAR BOOK of TRA (The Tire and Rim Association, Inc. ) in the United States, and the like (in other words, the above-described "rim" includes sizes that may be included in the aforementioned industrial standards in the future, as well as current sizes. Examples of the "sizes to be included in the future" may be sizes listed as "<NPL>. ), but in the case of a size not listed in these industrial standards, a rim with a width corresponding to a bead width of tires.

In this specification, "specified internal pressure" refers to an air pressure (maximum air pressure) corresponding to a maximum load capacity of a single wheel in the applicable size and ply rating described in the aforementioned JATMA YEAR BOOK or other industrial standards. In the case of sizes not listed in the aforementioned industrial standards, the "specified internal pressure" refers to an air pressure (maximum air pressure) corresponding to a maximum load capacity specified for each vehicle on which the tire is mounted.

"Maximum load" means a load corresponding to the maximum load capacity described above.

Air here can be replaced by inert gas such as nitrogen gas, or the like.

In this specification, unless otherwise noted, the dimensions of each of elements such as grooves and lands, a ground contact width (TW), and the like are measured in "standard condition" described below.

In this specification, the "standard condition" refers to a condition in which the tire is mounted on the rim, filled with the above specified internal pressure, and unloaded. Here, the dimensions of each of the elements in the tread surface such as the grooves and the lands, the ground contact width (TW), and the like are measured on a development view of the tread surface.

The tire according to each example described in this specification has at least two (in the example of <FIG>, only two) circumferential main grooves <NUM> on the tread surface <NUM>, as illustrated in <FIG>. The tire according to each example described in this specification is provided with at least a first circumferential main groove <NUM> and a second circumferential main groove <NUM>, as the circumferential main grooves <NUM>. Between at least the two circumferential main grooves <NUM> described above, one or more intermediate land portions <NUM> are partitioned. That is, the intermediate land portion <NUM> is partitioned between the first and second circumferential main grooves <NUM> and <NUM>.

In the example of <FIG>, a first end land portion <NUM> is partitioned between the first circumferential main groove <NUM> and a first ground contact edge TE1. In the example of <FIG>, a second end land portion <NUM> is partitioned between the second circumferential main groove <NUM> and a second ground contact edge TE2.

Each of the intermediate land portion <NUM>, the first end land portion <NUM>, and the second end land portion <NUM> is not divided by transverse grooves (excluding sipes) in a tire circumferential direction, but are continuous in the tire circumferential direction over the entire tire in the tire circumferential direction, i.e., rib-like land portions.

In the example in <FIG>, the first circumferential main groove <NUM>, the first ground contact edge TE1, and the first end land portion <NUM> are located on the vehicle-mounted outside (OUT side) with respect to the tire equatorial plane CL. The second circumferential main groove <NUM>, the second ground contact edge TE2, and the second end land portion <NUM> are located on the vehicle-mounted inside (IN side) with respect to the tire equatorial plane CL. The intermediate land portion <NUM> is located on the tire equatorial plane CL. However, the first ground contact edge TE1 and the first end land portion <NUM> may be located on the vehicle-mounted inside (IN side) with respect to the tire equatorial plane CL, and the second ground contact edge TE2 and the second end land portion <NUM> may be located on the vehicle-mounted outside (OUT side). The first circumferential main groove <NUM> and the second circumferential main groove <NUM> may be located on either side with respect to the tire equatorial plane CL. For example, the second circumferential main groove <NUM> may be located on the vehicle-mounted outside (OUT side) with respect to the tire equatorial plane CL, and the first circumferential main groove <NUM> may be located on the vehicle-mounted inside (IN side) with respect to the tire equatorial plane CL. The first and second circumferential main grooves <NUM> and <NUM> may be located on opposite sides to each other with respect to the tire equatorial plane CL, as in the example of <FIG>, or may be located on the same side as each other with respect to the tire equatorial plane CL. The intermediate land portion <NUM> may be located on the tire equatorial plane CL, as in the example of <FIG>, or may not be located on the tire equatorial plane CL.

In the tire according to each example described in this specification, maximum values of the groove depths D1 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves) provided in the tread surface <NUM> are <NUM>% or less of the groove widths W2 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves), respectively.

Therefore, in the tire according to each example described in this specification, the groove depths D1 (<FIG>) of the circumferential main grooves (in the example of <FIG>, the first and second circumferential main grooves) provided in the tread surface <NUM> are shallower than those of conventional general tires.

In each example described in this specification, as illustrated in <FIG>, a plurality of resonators <NUM> are formed in the intermediate land portion <NUM> partitioned between the first circumferential main groove <NUM> and the second circumferential main groove <NUM>. Each resonator <NUM> has an auxiliary groove <NUM>. It is preferable that the resonator <NUM> further have a branch groove <NUM>. Both ends of the auxiliary groove <NUM> terminate within the intermediate land portion <NUM>. The branch groove <NUM> extends so as to connect between the auxiliary groove <NUM> and the first circumferential main groove <NUM>, and the groove cross-sectional area of the branch groove <NUM> is smaller than that of the auxiliary groove <NUM>.

Here, the "groove cross-sectional area" of each of the branch groove <NUM>, the branch groove <NUM>, and the like is measured in the "standard condition" described above along a virtual plane perpendicular to a groove width centerline of each of the grooves.

In each example described in this specification, as described above, the maximum values of the groove depths D1 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves) provided in the tread surface <NUM> are <NUM>% or less of the groove widths W2 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves), respectively, that is, are shallower than those of conventional general tires. Thus, the thickness T1 (<FIG>) of the tread rubber <NUM> of the tire can be thinner than those of conventional general tires. This makes it possible to reduce the weight of the tire and the rolling resistance of the tire. In recent years, with the shift to eco-cars such as electric vehicles (EVs) and plug-in hybrid electric vehicles (PHEVs), a demand for reduction in the weight of car parts has been increasing, and a demand for reduction in the weight of tires is also increasing. In addition, there is a growing demand for reduced rolling resistance, as environmental regulations such as Europe's R117, for example, increasingly strictly regulate the rolling resistance of tires. The tire according to each example described in this specification can meet these requirements.

On the other hand, by simply making each circumferential main groove <NUM> shallower, as described above, and thus making the thickness T1 (<FIG>) of the tread rubber <NUM> thinner, the rigidity of the tire increases and vibration is transmitted more easily, so that input from a road surface becomes stronger during rolling of the tire and noise (in particular, passing noise) tends to be generated more easily. Therefore, in the tire according to each example described in this specification, as described above, the resonators <NUM> are formed in the intermediate land portion <NUM> partitioned between the first and second circumferential main grooves <NUM> and <NUM>. By forming the resonator <NUM>, during rolling of the tire, air flowing in the first circumferential main groove <NUM> flows into the resonator <NUM>, thereby dispersing a frequency and reducing noise. This reduces increase in noise (passing noise) owing to the shallowness of each circumferential main groove <NUM>. In addition, environmental regulations such as R117 in Europe, for example, have become stricter in regulating tire noise, and a demand for reduction in noise is also increasing. The tire according to each example described in this specification can meet such a demand.

As described above, according to the tire of each example described in this specification, noise can be suppressed, while the groove depths of the circumferential main grooves are made shallow.

A suitable configuration, variations, and the like will be described below in the tire according to each example described in this specification.

In the tire according to each example described in this specification, the maximum values of the groove depths D1 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves) are more preferably <NUM>% or less of the groove widths W2 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves), respectively. This allows the groove depths of the circumferential main grooves to be shallower. Thus, the thickness T1 (<FIG>) of the tread rubber <NUM> can be made thinner, making it easier to reduce the tire weight and rolling resistance.

Similarly, from the viewpoint of making the groove depths of the circumferential main grooves shallower, the maximum value of the groove depth D1 (<FIG>) of each of the circumferential main grooves <NUM> (in the example in <FIG>, the first and second circumferential main grooves) is preferably <NUM> or less, and more preferably <NUM> or less.

Similarly, from the viewpoint of making the groove depths of the circumferential main grooves shallower, the maximum value of the groove depth D1 (<FIG>) of each of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves) is preferably <NUM>% or less of the thickness T1 (<FIG>) of the tread rubber <NUM>, and more preferably <NUM>% or less.

On the other hand, in the tire according to each example described in this specification, minimum values of the groove depths D1 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves) are preferably <NUM>% or more of the groove widths W2 (<FIG>) of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves), and more preferably <NUM>% or more, respectively. This improves drainage.

Similarly, from the viewpoint of drainage, the minimum value of the groove depth D1 (<FIG>) of each of the circumferential main grooves <NUM> (in the example in <FIG>, the first and second circumferential main grooves) is preferably <NUM> or more, and more preferably <NUM> or more.

Similarly, from the viewpoint of drainage, the minimum value of the groove depth D1 (<FIG>) of each of the circumferential main grooves <NUM> (in the example of <FIG>, the first and second circumferential main grooves) is preferably <NUM>% or more of the thickness T1 (<FIG>) of the tread rubber <NUM>, and more preferably <NUM>% or more.

The groove depth D1 of each of the circumferential main grooves <NUM> may be constant along the tire circumferential direction or may vary along the tire circumferential direction.

Here, the "maximum value of the groove depth (D1) of each of the circumferential main grooves (<NUM>)" refers to a groove depth (D1) at a portion at which the groove depth (D1) of each of the circumferential main grooves (<NUM>) is maximized. The "minimum value of the groove depth (D1) of each of the circumferential main grooves (<NUM>)" refers to a groove depth (D1) at a portion at which the groove depth (D1) of each of the circumferential main grooves (<NUM>) is minimized.

In the tire according to each example described in this specification, the groove width W2 (<FIG>) of each of the circumferential main grooves <NUM> (in the example in <FIG>, the first and second circumferential main grooves) is preferably <NUM>% or more of the ground contact width TW. This improves drainage.

Similarly, from the viewpoint of drainage, the groove width W2 (<FIG>) of each of the circumferential main grooves <NUM> (in the example in <FIG>, the first and second circumferential main grooves) is preferably <NUM> or more.

On the other hand, in the tire according to each example described in this specification, the groove width W2 (<FIG>) of each of the circumferential main grooves <NUM> (in the example in <FIG>, the first and second circumferential main grooves) is preferably <NUM>% or less of the ground contact width TW. This ensures sufficient rigidity.

Similarly, from the viewpoint of rigidity, the groove width W2 (<FIG>) of each of the circumferential main grooves <NUM> (in the example in <FIG>, the first and second circumferential main grooves) is preferably <NUM> or less.

These ranges of the groove width W2 are particularly preferable in a case in which the number of the circumferential main grooves <NUM> provided in the tread surface <NUM> is two.

In this specification, the "ground contact width (TW)" means the distance between the pair of ground contact edges (TE1, TE2) in the tire width direction, measured along the tread surface <NUM>.

In the tire according to each example described in this specification, a maximum value of the thickness T1 (<FIG>) of the tread rubber <NUM> is preferably <NUM> or less. This enables reduction in tire weight and rolling resistance.

Similarly, from the viewpoint of reduction in tire weight and rolling resistance, the maximum value of the thickness T1 (<FIG>) of the tread rubber <NUM> is preferably <NUM>% or less of a maximum value of a gauge T2 (<FIG>) of the tread portion <NUM>.

On the other hand, in the tire according to each example described in this specification, the maximum value of the thickness T1 (<FIG>) of the tread rubber <NUM> is preferably <NUM> or more. This improves the handling stability performance and ride comfort performance of the tire.

Similarly, from the viewpoint of handling stability performance and ride comfort performance, the maximum value of the thickness T1 (<FIG>) of the tread rubber <NUM> is preferably <NUM>% or more of the maximum value of the gauge T2 (<FIG>) of the tread portion <NUM>.

Here, the "maximum value of the thickness (T1) of the tread rubber (<NUM>)" refers to a thickness (T1) at a portion at which the thickness (T1) of the tread rubber (<NUM>) is maximized. The "maximum value of the gauge (T2) of the tread portion (<NUM>)" refers to a gauge (T2) at a portion at which the gauge (T2) of the tread portion (<NUM>) is maximized.

In the tire according to each example described in this specification, a maximum value of the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM>% or less of a maximum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM>, and more preferably <NUM>% or less of the maximum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM>. The provision of the resonator <NUM>, as described above, makes it possible to suppress increase in noise, which can be caused by making the circumferential main grooves <NUM> shallower. By making the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> narrower, the rigidity of the tread portion <NUM> (in particular, the intermediate land portion <NUM>) can be increased, thereby reduction in the rigidity of the tread portion <NUM> (in particular, the intermediate land portion <NUM>), which is caused by the provision of the resonators <NUM> can be suppressed.

Similarly, from the viewpoint of rigidity, the maximum value of the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> or less.

Similarly, from the viewpoint of rigidity, the maximum value of the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM>% or less of the maximum value of the groove depth D1 (<FIG>) of the first circumferential main groove <NUM>, and more preferably <NUM>% or less of the maximum value of the groove depth D1 (<FIG>) of the first circumferential main groove <NUM>.

On the other hand, in the tire according to each example described in this specification, the maximum value of the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM>% or more of the maximum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM>. This improves noise reduction performance of the resonator <NUM>.

Similarly, from the viewpoint of noise reduction performance, the maximum value of the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> or more.

Similarly, from the viewpoint of noise reduction performance, the maximum value of the groove width W3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM>% or more of the maximum value of the groove depth D1 (<FIG>) of the first circumferential main groove <NUM>.

The groove width W3 of the auxiliary groove <NUM> may vary along an extending direction of the auxiliary groove <NUM>, as in the example of <FIG>, or may be constant along the extending direction of the auxiliary groove <NUM>.

Here, the "maximum value of the groove width (W3) of the auxiliary groove (<NUM>)" refers to a groove width (W3) at a portion at which the groove width (W3) of the auxiliary groove (<NUM>) is maximized.

Here, the groove width W3 of the auxiliary groove <NUM> is measured perpendicularly to a groove width centerline 211c of the auxiliary groove <NUM>.

In the tire according to each example described in this specification, a minimum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> or more, and more preferably <NUM> or more. Therefore, deepening the groove depth D3 of the auxiliary groove <NUM> increases the volume of the auxiliary groove <NUM>, and thus improves the noise reduction performance of the resonator <NUM> (and thereby suppresses noise increase). This is particularly preferable in a case in which the groove width W3 (<FIG>) of the auxiliary groove <NUM> is narrowed as described above.

Similarly, from the viewpoint of noise reduction performance, the minimum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM>% or more of the maximum value of the groove depth D1 (<FIG>) of the first circumferential main groove <NUM>.

On the other hand, in the tire according to each example described in this specification, the maximum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> or less. Thereby, it is possible to suppress reduction in the rigidity of the tread portion <NUM> (in particular, the intermediate land portion <NUM>), which can be caused by the provision of the resonators <NUM>.

Similarly, from the viewpoint of the rigidity, the maximum value of the groove depth D3 (<FIG>) of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM>% or less of the maximum value of the groove depth D1 (<FIG>) of the first circumferential main groove <NUM>.

The groove depth D3 of the auxiliary groove <NUM> may be constant along the extending direction of the auxiliary groove <NUM>, or may vary along the extending direction of the auxiliary groove <NUM>.

Here, the "minimum value of the groove width (W3) of the auxiliary groove (<NUM>)" refers to a groove depth (D3) at a portion at which the groove depth (D3) of the auxiliary groove (<NUM>) is minimized. The "maximum value of the groove width (W3) of the auxiliary groove (<NUM>)" refers to a groove depth (D3) at a portion at which the groove depth (D3) of the auxiliary groove (<NUM>) is maximized. The "extending direction of the auxiliary groove (<NUM>)" is an extending direction of the groove width centerline (211c) of the auxiliary groove (<NUM>).

In the tire according to each example described in this specification, a minimum value of the groove depth D2 (<FIG>) of the branch groove <NUM> of the resonator <NUM> is preferably <NUM>% or more of the groove depth D1 of the first circumferential main groove <NUM>. Therefore, by deepening the groove depth D2 of the branch groove <NUM>, wear of the tread portion <NUM> (in particular, a block portion 20b of the intermediate land portion <NUM>) can be reduced. In addition, in a case in which the circumferential main grooves <NUM> are made shallow and thus the thickness T1 of the tread rubber <NUM> is made thinner, as described above, the rigidity of the tread portion <NUM> tends to increase. Therefore, deepening the groove depth D2 of the branch grooves <NUM> in this manner can effectively reduce wear, while ensuring sufficient rigidity.

On the other hand, in the tire according to each example described in this specification, the maximum value of the groove depth D2 (<FIG>) of the branch groove <NUM> of the resonator <NUM> is preferably <NUM>% or less of the groove depth D1 of the first circumferential main groove <NUM>. This allows increase in rigidity.

The groove depth D2 of the branch groove <NUM> may be constant along an extending direction of the branch groove <NUM>, or may vary along the extending direction of the branch groove <NUM>.

Here, the "minimum value of the groove depth (D2) of the branch groove (<NUM>)" refers to a groove depth (D2) at a portion at which the groove depth (D2) of the branch groove (<NUM>) is minimized. The "maximum value of the groove depth (D2) of the branch groove (<NUM>)" refers to a groove depth (D2) at a portion at which the groove depth (D2) of the branch groove (<NUM>) is maximized. The "extending direction of the branch groove (<NUM>)" is an extending direction of a groove width centerline of the branch groove (<NUM>).

In the tire according to each example described in this specification, as in the example of <FIG>, the auxiliary groove <NUM> of the resonator <NUM> may have a first auxiliary groove portion <NUM>, which extends to the first tire circumferential side CD1 as being gradually far from the first circumferential main groove <NUM>, and a second auxiliary groove portion <NUM>, which is continuous from an end of the first auxiliary groove portion <NUM> on a side close to the first circumferential main groove <NUM>, of both ends of the first auxiliary groove portion <NUM> in the extending direction, and extends to the second tire circumferential side CD2. In this case, an acute angle-side inclination angle θ6 (<FIG>) at an end of the second auxiliary groove portion <NUM>, on a side connecting to the first auxiliary groove portion <NUM>, with respect to the tire width direction is preferably larger than an acute angle-side inclination angle θ4 (<FIG>) at an end of the first auxiliary groove portion <NUM>, on a side connecting to the second auxiliary groove portion <NUM>, with respect to the tire width direction. The provision of the second auxiliary groove portion <NUM>, in addition to the first auxiliary groove portion <NUM>, in the auxiliary groove <NUM> makes it possible to increase in the overall length of the auxiliary groove <NUM>. This allows the volume of the auxiliary groove <NUM> to be increased, which thus improves the noise reduction performance of the resonator <NUM>. In addition, the second auxiliary groove portion <NUM> can reduce compression rigidity.

The second auxiliary groove portion <NUM> preferably extends to the second tire circumferential side CD2, as being gradually close to the first circumferential main groove <NUM>, as in the example in <FIG>. However, the second auxiliary groove portion <NUM> may extend to the second tire circumferential side CD2 while extending in parallel with the first circumferential main groove <NUM>, or the second auxiliary groove portion <NUM> may extend to the second tire circumferential side CD2 as being gradually far from the first circumferential main groove <NUM>.

However, the auxiliary groove <NUM> may have only the first auxiliary groove portion <NUM>, without having the second auxiliary groove portion <NUM>.

In the tire according to each example described in this specification, the acute angle-side inclination angle θ6 (<FIG>) at an end of the second auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>, on the side connecting to the first auxiliary groove portion <NUM>, with respect to the tire width direction is preferably <NUM> to <NUM> times the acute angle-side inclination angle θ4 (<FIG>) at the end of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>, on the side connecting to the second auxiliary groove portion <NUM>, with respect to the tire width direction.

In the tire according to each example described in this specification, an acute angle-side inclination angle θ5 (<FIG>) at an end of the second auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>, on the side terminating within the intermediate land portion <NUM>, with respect to the tire width direction is preferably <NUM> to <NUM> times the acute angle-side inclination angle θ6 (<FIG>) at the end of the second auxiliary groove portion <NUM>, on the side connecting to the first auxiliary groove portion <NUM>, with respect to the tire width direction.

In the tire according to each example described in this specification, it is preferable that the groove width of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> gradually decrease toward the first tire circumferential side CD1, as in the example of <FIG>.

In the tire according to each example described in this specification, it is preferable that the groove width of the second auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> gradually decrease toward the second tire circumferential side CD2, as in the example of <FIG>.

In the tire according to each example described in this specification, an acute angle-side inclination angle θ1 (<FIG>) at an end of the branch groove <NUM> of the resonator <NUM>, on the side open to the first circumferential main groove <NUM> (more specifically, an end located at the boundary between the intermediate land portion <NUM> and the first circumferential main groove <NUM>), with respect to the tire width direction is preferably <NUM>° or more. Thereby, the rigidity of a corner portion 20c of the block portion 20b, which is partitioned between the branch groove <NUM> and the first circumferential main groove <NUM>, of the intermediate land portion <NUM> is sufficiently enhanced, and the corner portion 20c can be prevented from coming off.

On the other hand, in the tire according to each example described in this specification, the acute angle-side inclination angle θ1 (<FIG>) at the end of the branch groove <NUM> of the resonator <NUM>, on the side open to the first circumferential main groove <NUM>, with respect to the tire width direction is preferably <NUM>° or less, and more preferably <NUM>° or less. This makes it possible to provide a sufficient length L3 of the branch groove <NUM>, which thus improves the noise reduction performance of the resonator <NUM>.

In the tire according to each example described in this specification, an acute angle-side inclination angle θ2 (<FIG>) at an end of the branch groove <NUM> of the resonator <NUM>, on a side far from the first circumferential main groove <NUM>, with respect to the tire width direction is preferably <NUM>° or more.

On the other hand, in the tire according to each example described in this specification, the acute angle-side inclination angle θ2 (<FIG>) at the end of the branch groove <NUM> of the resonator <NUM>, on the side far from the first circumferential main groove <NUM>, with respect to the tire width direction is preferably <NUM>° or less, and more preferably <NUM>° or less.

In the tire according to each example described in this specification, the acute angle-side inclination angle of the branch groove <NUM> of the resonator <NUM> with respect to the tire width direction may be constant along the tire width direction, as in the example of <FIG>, or the acute angle-side inclination angle with respect to the tire width direction may gradually increase, as being gradually far from the first circumferential main groove <NUM>.

In the tire according to each example described in this specification, an acute angle-side inclination angle θ3 (<FIG>) at an end of the auxiliary groove <NUM> of the resonator <NUM>, on a side far from the first circumferential main groove <NUM>, with respect to the tire width direction is preferably larger than the acute angle-side inclination angle θ1 (<FIG>) at the end of the branch groove <NUM> of the resonator <NUM>, on the side open to the first circumferential main groove <NUM>, with respect to the tire width direction.

This allows increase in the length of the auxiliary groove <NUM> (specifically, the length L1 of the first auxiliary groove portion <NUM>), while ensuring the sufficient rigidity of the corner portion 20c of the block portion 20b partitioned between the branch groove <NUM> and the first circumferential main groove <NUM>, which thus improves the noise reduction performance of the resonator <NUM>.

From the same viewpoint, the acute angle-side inclination angle θ3 (<FIG>) at the end of the auxiliary groove <NUM> of the resonator <NUM>, on the side far from the first circumferential main groove <NUM>, with respect to the tire width direction is preferably <NUM>° or more and <NUM>° or less.

However, the inclination angle θ3 may be the same as the inclination angle θ1.

In the tire according to each example described in this specification, it is preferable that, as in the example of <FIG>, the acute angle-side inclination angle of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> with respect to the tire width direction gradually increase, as being far from the first circumferential main groove <NUM>.

From the same viewpoint, in the tire according to the each example described in this specification, it is preferable that, as in the example of <FIG>, the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> be convexly curved to the second tire circumferential side CD2.

However, the acute angle-side inclination angle of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> with respect to the tire width direction may be constant and linearly extend along the tire width direction.

In the tire according to each example described in this specification, the acute angle-side inclination angle θ4 (<FIG>) at the end of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>, on the side connecting to the second auxiliary groove portion <NUM>, with respect to the tire width direction is preferably <NUM> to <NUM> times the acute angle-side inclination angle θ2 (<FIG>) at the end of the branch groove <NUM> of the resonator <NUM>, on the side far from the first circumferential main groove <NUM>, with respect to the tire width direction.

In the tire according to each example described in this specification, the length L1 of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> or more times the length L2 of the second auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>. This allows the overall length of the auxiliary groove <NUM> (in particular, the length L1 of the first auxiliary groove portion <NUM>) to be lengthened, which thus increases the volume of the auxiliary groove <NUM> and improves the noise reduction performance of the resonator <NUM>.

On the other hand, in the tire according to each example described in this specification, the length L1 of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> or less times the length L2 of the second auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>, and more preferably <NUM> or less times the length L2 of the second auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM>. Thereby, reduction in rigidity of the intermediate land portion <NUM> can be suppressed.

The "length (L1) of the first auxiliary groove portion (<NUM>)" refers to the length of the groove width centerline (211c) of the first auxiliary groove portion (<NUM>). The "length (L2) of the second auxiliary groove portion (<NUM>)" refers to the length of the groove width centerline (211c) of the second auxiliary groove portion (<NUM>).

In the tire according to each example described in this specification, the length L1 of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> to <NUM>% of the ground contact width TW.

Thereby, the length of the auxiliary groove <NUM> (in particular, the length L1 of the first auxiliary groove portion <NUM>) can be lengthened and rigidity can be enhanced.

From the same viewpoint, the length L1 of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> to <NUM>.

In the tire according to each example described in this specification, the length L1 of the first auxiliary groove portion <NUM> of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> to <NUM> times the length L3 of the branch groove <NUM> of the resonator <NUM>.

Thereby, rigidity is enhanced while noise is further suppressed.

From the same viewpoint, the length L3 of the branch groove <NUM> of the resonator <NUM> is preferably <NUM> to <NUM>% of the ground contact width TW.

From the same viewpoint, the length L3 of the branch groove <NUM> of the resonator <NUM> is preferably <NUM> to <NUM>.

The "length (L3) of the branch groove (<NUM>)" refers to the length of a groove width centerline of the branch groove (<NUM>).

In the tire according to each example described in this specification, the volume of the auxiliary groove <NUM> of the resonator <NUM> is preferably <NUM> to <NUM><NUM>.

In the tire according to each example described in this specification, as in the example of <FIG>, the branch groove <NUM> of the resonator <NUM> is preferably connected to a connecting portion between the first auxiliary groove portion <NUM> and the second auxiliary groove portion <NUM> in the auxiliary groove <NUM> of the resonator <NUM>.

Thereby, air entering the branch groove <NUM> from the first circumferential main groove <NUM> can smoothly get into the auxiliary groove <NUM>, so noise can be further suppressed.

However, the branch groove <NUM> of the resonator <NUM> may be connected to any portion of the auxiliary groove <NUM> of the resonator <NUM>.

In a case in which the auxiliary groove <NUM> has only the first auxiliary groove portion <NUM>, without having the second auxiliary groove portion <NUM>, the branch groove <NUM> is preferably connected to the end of the first auxiliary groove portion <NUM> on the side close to the first circumferential main groove <NUM>.

In the tire according to each example described in this specification, as illustrated in <FIG>, the branch groove <NUM> of the resonator <NUM> preferably includes a tread surface-side sipe portion <NUM>, which is open to the tread surface <NUM> and extends inward in the tire radial direction, and a tunnel portion <NUM>, which extends continuously from the tread surface-side sipe portion <NUM> inward in the tire radial direction and has a larger groove width than the tread surface-side sipe portion <NUM>.

Since the branch groove <NUM> has the tread surface-side sipe portion <NUM> outside in the tire radial direction, the block portion 20b partitioned between the pair of branch grooves <NUM> adjacent in the tire circumferential direction, of the intermediate land portion <NUM>, is prevented from collapsing when the tire is rolling. Since the branch groove <NUM> has the tunnel portion <NUM> inside in the tire radial direction, it is possible to provide a passage of air to the resonator <NUM> and thus improve the noise reduction performance of the resonator <NUM>.

In this way, it is possible to prevent reduction in rigidity owing to the provision of the resonators, while noise is suppressed.

From the viewpoint of preventing the intermediate land portion <NUM> from collapsing during rolling of the tire, the groove width (sipe width) of the tread surface-side sipe portion <NUM> is preferably <NUM> or less.

Similarly, from the viewpoint of preventing the intermediate land portion <NUM> from collapsing during rolling of the tire, the tread surface-side sipe portion <NUM> is preferably configured to close (a pair of sipe walls opposite each other contact at least partially) directly under a load, when the tire is mounted on the rim, filled with the above-described specified internal pressure, and under the maximum load.

From the viewpoint of providing the passage of air to the resonator <NUM> during rolling of the tire, the groove width of the tunnel portion <NUM> is preferably <NUM> or more.

Similarly, from the viewpoint of providing the passage of air to the resonator <NUM> during rolling of the tire, the tunnel portion <NUM> is preferably configured not to close (the pair of sipe walls opposite each other do not contact at any part) directly under a load, when the tire is mounted on the rim, filled with the above-described specified internal pressure, and under the maximum load.

On the other hand, from the viewpoint of improving the noise reduction performance of the resonator <NUM>, the groove width of the tunnel portion <NUM> is preferably <NUM> or less.

In the tire according to each example described in this specification, in a case in which the branch groove <NUM> of the resonator <NUM> has the tread surface-side sipe portion <NUM> and the tunnel portion <NUM>, as described above, the branch groove <NUM> of the resonator <NUM> preferably further includes a bottom-side sipe portion <NUM>, which extends continuously from the tunnel portion <NUM> inward in the tire radial direction and has a smaller groove width than the tunnel portion <NUM>. This improves the noise reduction performance of the resonator <NUM>.

In this case, the groove width (sipe width) of the bottom-side sipe portion <NUM> is preferably the same as the groove width (sipe width) of the tread surface-side sipe portion <NUM>.

In the tire according to each example described in this specification, as in the example illustrated in <FIG> and <FIG>, groove walls 10a of each of the circumferential main grooves <NUM> (in the example of the drawings, the first and second circumferential main grooves <NUM> and <NUM>) are preferably convexly curved inward in the tire radial direction and outward in the groove width direction. In other words, the groove walls 10a of each of the circumferential main grooves <NUM> (in the example of the drawings, the first and second circumferential main grooves <NUM> and <NUM>) are rounded.

As illustrated in <FIG>, the branch groove <NUM> of the resonator <NUM> preferably extends to the groove wall 10a of the first circumferential main groove <NUM>. The branch groove <NUM> preferably extends to the rounded groove wall 10a of the first circumferential main groove <NUM>. In this case, a portion of the branch groove <NUM> that extends along the groove wall 10a of the first circumferential main groove <NUM> constitutes an opening extended portion 212a.

Therefore, by forming the branch groove <NUM> deeper, wear of the tread portion <NUM> (in particular, the block portion 20b of the intermediate land portion <NUM>) can be reduced. In addition, in a case in which the circumferential main grooves <NUM> are made shallow and thus the thickness T1 of the tread rubber <NUM> is made thinner, as described above, the rigidity of the tread portion <NUM> tends to increase. Therefore, forming the branch grooves <NUM> deeper, in this manner, can effectively reduce wear, while ensuring sufficient rigidity.

The opening extended portion 212a allows air in the first circumferential main groove <NUM> to easily get into the branch groove <NUM>, which thus improves the noise reduction performance of the resonator <NUM>. Therefore, noise can be further suppressed.

Here, "outward in the groove width direction" refers to a side far from the groove width centerline.

In the cross-section in the tire width direction (<FIG>), the radius of curvature R of the groove walls 10a of each of the circumferential main grooves <NUM> (in the example of the drawings, the first and second circumferential main grooves <NUM> and <NUM>) is preferably <NUM> to <NUM>.

As in the example of <FIG>, an inner end of the opening extended portion 212a of the branch groove <NUM> in the tire radial direction is preferably positioned inside in the tire radial direction, with respect to a center of the first circumferential main groove <NUM> in a groove depth direction (a center between an opening end surface of the first circumferential main groove <NUM> open to the tread surface <NUM> and a groove bottom of the first circumferential main groove <NUM>), and more preferably situated at the same position as the groove bottom of the first circumferential main groove <NUM> in the tire radial direction.

As in the example of <FIG>, the branch groove <NUM> (specifically, the opening extended portion 212a of the branch groove <NUM>) preferably terminates at the vicinity of the boundary between the groove wall 10a and the groove bottom of the first circumferential main groove <NUM>.

In the tire according to each example described in this specification, as in the example illustrated in <FIG>, the tunnel portion <NUM> of the branch groove <NUM> of the resonator <NUM> is preferably open to the groove wall 10a (rounded groove wall 10a) of the first circumferential main groove <NUM>.

This allows air in the first circumferential main groove <NUM> to easily get into the branch groove <NUM>, which thus improves the noise reduction performance of the resonator <NUM>. Therefore, noise can be further suppressed.

In the tire according to each example described in this specification, a pitch P1 (<FIG>) between the branch grooves <NUM> of the resonators <NUM> in the tire circumferential direction is preferably <NUM> or more times the groove depth D2 (<FIG>) of the branch grooves <NUM>. Thereby, reduction in rigidity, owing to the provision of the resonators <NUM>, can be prevented.

On the other hand, in the tire according to each example described in this specification, the pitch P1 (<FIG>) between the branch grooves <NUM> of the resonators <NUM> in the tire circumferential direction is preferably <NUM> or less times the groove depth D2 (<FIG>) the branch grooves <NUM>. Thereby, wear of the tread portion <NUM> (in particular, the intermediate land portion <NUM>) can be prevented.

In the tire according to each example described in this specification, the width W1 of the intermediate land portion <NUM> is preferably <NUM> to <NUM>% of the ground contact width TW of the tire. Thereby, reduction in rigidity, owing to the provision of the resonators, can be prevented.

Similarly, in the tire according to each example described in this specification, the width W1 of the intermediate land portion <NUM> is preferably <NUM> to <NUM>.

In the tire according to each example described in this specification, the intermediate land portion <NUM> is preferably provided with a plurality of intermediate land sipes <NUM> each of whose one end is open to the second circumferential main groove <NUM> and the other end terminates within the intermediate land portion <NUM>. Thereby, wear of the tread portion <NUM> (in particular, the intermediate land portion <NUM>) can be prevented.

As in the example of <FIG>, each of the intermediate land sipes <NUM> preferably extends gradually to the second tire circumferential side CD2, as being far from the second circumferential main groove <NUM>.

As in the example of <FIG>, each of the intermediate land sipes <NUM> preferably terminates before the tire equatorial plane CL.

Each of the intermediate land sipes <NUM> is preferably configured to close (a pair of sipe walls opposite each other contact at least partially) directly under a load, when the tire is mounted on the rim, filled with the above-described specified internal pressure, and under the maximum load.

A pitch P2 (<FIG>) between the intermediate land sipes <NUM> in the tire circumferential direction is preferably <NUM> to <NUM> times the pitch P1 (<FIG>) between the branch grooves <NUM> of the resonators <NUM> in the tire circumferential direction.

In the tire according to each example described in this specification, the first end land portion <NUM> is preferably provided with a plurality of first end land portion lug grooves <NUM> each of whose one end is open to the first ground contact edge TE1 and the other end terminates within the first end land portion <NUM>. This improves drainage while enhancing rigidity.

As in the example of <FIG>, each of the first end land portion lug grooves <NUM> preferably extends gradually to the first tire circumferential side CD1, as being far from the first ground contact edge TE1.

The groove width of each of the first end land portion lug grooves <NUM> is preferably <NUM> to <NUM>, for example.

A pitch P3 (<FIG>) between the first end land portion lug grooves <NUM> in the tire circumferential direction is preferably <NUM> to <NUM> times the pitch P1 (<FIG>) of the branch grooves <NUM> of the resonators <NUM> in the tire circumferential direction.

In the tire according to each example described in this specification, the second end land portion <NUM> is preferably provided with a plurality of second end land portion lug grooves <NUM> each of whose one end is open to the second ground contact edge TE2 and the other end terminates within the second end land portion <NUM>. This improves drainage while enhancing rigidity.

As in the example of <FIG>, each of the second end land portion lug grooves <NUM> preferably extends gradually to the second tire circumferential side CD2, as being far from the second ground contact edge TE2.

The groove width of each of the second end land portion lug grooves <NUM> is preferably <NUM> to <NUM>, for example.

A pitch P4 (<FIG>) between the second end land portion lug grooves <NUM> in the tire circumferential direction is preferably <NUM> to <NUM> times the pitch P1 (<FIG>) of the branch grooves <NUM> of the resonators <NUM> in the tire circumferential direction.

In the tire according to each example described in this specification, in a case in which the second end land portion <NUM> is provided with the second end land portion lug grooves <NUM>, as described above, the second end land portion <NUM> is preferably further provided with a plurality of connecting sipes <NUM> each of which extends so as to connect between the second end land portion lug groove <NUM> and the second circumferential main groove <NUM>.

As in the example of <FIG>, each of the connecting sipes <NUM> preferably extends gradually to the second tire circumferential side CD2, as being far from the second ground contact edge TE2.

Although not illustrated in the drawings, each of the connecting sipes <NUM> preferably has a tread surface-side sipe portion, which is open to the tread surface <NUM> and extends inward in the tire radial direction, and a tunnel portion, which extends continuously from the tread surface-side sipe portion inward in the tire radial direction and has a larger groove width than the tread surface-side sipe portion, just as with the branch groove <NUM> of the resonator <NUM>. Thereby, air in the second circumferential main groove <NUM> can get into the second end land portion lug grooves <NUM> through the tunnel portions of the connecting sipes <NUM>, so noise can be reduced. In this case, the tread surface-side sipe portion is preferably configured to close (a pair of sipe walls opposite each other contact at least partially) directly under a load, when the tire is mounted on the rim, filled with the above-described specified internal pressure, and under the maximum load.

In the tire according to each example described in this specification, in a case in which the second end land portion <NUM> is provide with the second end land portion lug grooves <NUM>, as described above, the second end land portion <NUM> is preferably further provided with a plurality of second end land portion sipes <NUM> each of whose one end is open to the second ground contact edge TE2 and the other end is open to the second circumferential main groove <NUM>, between a pair of the second end land portion lug grooves <NUM> adjacent to each other in the tire circumferential direction.

As in the example of <FIG>, each of the second end land portion sipes <NUM> preferably extends gradually to the second tire circumferential side CD2, as being far from the second ground contact edge TE2.

In the tire according to each example described in this specification, the resonators <NUM> may be disposed only on one side with respect to the tire equatorial plane CL. In this case, the resonators <NUM> may be disposed only on the vehicle-mounted outside (OUT side), as in the example of <FIG>, or only on the vehicle-mounted inside (IN side) with respect to the tire equatorial plane CL.

Alternatively, the resonators <NUM> may be disposed on the tire equatorial plane CL.

Alternatively, as in a first variation illustrated in <FIG>, the resonators <NUM> may be disposed on both sides with respect to the tire equatorial plane CL. In this case, in each of the resonators <NUM> that are located on the side of the second circumferential main groove <NUM> with respect to the tire equatorial plane CL, both ends of the auxiliary groove <NUM> terminate within the intermediate land portion <NUM>, the branch groove <NUM> extends so as to connect between the auxiliary groove <NUM> and the second circumferential main groove <NUM>, and the branch groove <NUM> has a smaller groove cross-sectional area than the auxiliary groove <NUM>.

In the tire according to each example described in this specification, the intermediate land portion <NUM> is preferably located on the tire equatorial plane CL. This allows more effective reduction in noise.

In the tire according to each example described in this specification, as in a second variation illustrated in <FIG>, the intermediate land portion <NUM> may be provided with a narrow groove <NUM> on the tire equatorial plane CL. In this case, drainage can be improved.

However, the tire without the narrow groove <NUM>, as in the example of <FIG>, has the intermediate land portion <NUM> with improved rigidity.

In the case of providing the narrow groove <NUM>, the groove width of the narrow groove <NUM> is preferably <NUM>% or less of the ground contact width TW.

The groove depth of the narrow groove <NUM> is preferably <NUM>% or less of the groove depth D1 (<FIG>) of each of the circumferential main grooves <NUM> (in the example of the drawings, the first and second circumferential main grooves <NUM> and <NUM>), and more preferably <NUM>% or less.

In the tire according to each example described in this specification, the negative ratio of the tread surface <NUM> is preferably <NUM> to <NUM>%, and more preferably <NUM> to <NUM>%.

This allows sufficient drainage while preventing reduction in rigidity owing to the provision of the resonators <NUM>.

In this specification, the "negative ratio of the tread surface (<NUM>)" means the ratio of the area of a part of the tread surface (<NUM>) that does not contact a road surface to the total area of the tread surface (<NUM>), when the tire is mounted on the rim, filled with an internal pressure of the tire of <NUM> kPa, and under a load of <NUM> kN applied to the tire. The "part of the tread surface (<NUM>) that does not contact a road surface" is constituted of various types of grooves and the like in the tread surface (<NUM>).

Claim 1:
A tire comprising a first circumferential main groove (<NUM>) and a second circumferential main groove (<NUM>) in a tread surface (<NUM>),
wherein
a resonator (<NUM>) is formed in an intermediate land portion (<NUM>) partitioned between the first circumferential main groove (<NUM>) and the second circumferential main groove (<NUM>), and
the resonator (<NUM>) comprises an auxiliary groove (<NUM>) whose both ends terminate within the intermediate land portion (<NUM>), characterized in that
groove depths D1 of the first and second circumferential main grooves (<NUM>, <NUM>) are <NUM>% or less of groove widths W2 of the first and second circumferential main grooves (<NUM>, <NUM>), respectively, and
the groove width W3 of the auxiliary groove (<NUM>) of the resonator (<NUM>) is <NUM>% or less of the groove depth D1 of the first circumferential main groove (<NUM>).