JP2011011741A

JP2011011741A - Tire

Info

Publication number: JP2011011741A
Application number: JP2010207377A
Authority: JP
Inventors: Koyo Kiwaki; 幸洋木脇
Original assignee: Bridgestone Corp
Current assignee: Bridgestone Corp
Priority date: 2009-05-22
Filing date: 2010-09-15
Publication date: 2011-01-20
Anticipated expiration: 2029-11-30
Also published as: JP5135402B2

Abstract

PROBLEM TO BE SOLVED: To provide a tire effectively reducing air columnar resonance while preventing biting of pebbles or the like when a Helmholtz type resonator is provided, having an air chamber part forming a certain space by contact with a road surface, and a narrow groove part communicated with the air chamber part and a circumferential groove.SOLUTION: A pneumatic tire 10 is provided in a rib-like land section 110 thereof with: an air chamber section 130A in which recessed portions 131 are repeated in the circumferential direction of the tire at predetermined intervals; and narrow groove sections 121 which communicate with the recessed portions 131. A height H changes in the circumferential direction of the tire. A position of a bottom surface 132 is substantially the same as a contact surface in the highest position wherein a height to the contact surface is the most highest. The volume of the space formed between each narrow groove section 121 and the road surface is less than the volume of the space formed between each recessed portion 131 and the road surface. An end 121a of the narrow groove section 121 communicates with the recessed portion 131, and an end 121b of the narrow groove section 121 communicates with the circumferential groove 11.

Description

本発明は、タイヤ周方向に沿って延びる周方向溝に隣接したリブ状陸部を備えるタイヤに関し、特に、気室部と狭窄溝部とを有するヘルムホルツ型共鳴器がリブ状陸部に設けられたタイヤに関する。 The present invention relates to a tire including a rib-like land portion adjacent to a circumferential groove extending along the tire circumferential direction, and in particular, a Helmholtz resonator having an air chamber portion and a narrowed groove portion is provided in the rib-like land portion. Regarding tires.

近年、乗用自動車などでは、車両騒音（風切り音や機械音など）の低減化が一層進展したことや、環境へのさらなる配慮に伴って、タイヤ騒音の低減化の要求が以前にも増して高まっている。 In recent years, demand for reducing tire noise has increased in passenger cars, etc., due to further progress in reducing vehicle noise (wind noise, mechanical noise, etc.) and further consideration for the environment. ing.

タイヤ騒音のうち、タイヤ周方向に沿って延びる周方向溝と路面とによって形成される気柱管共鳴音を低減するため、トレッドが路面と接触することによって一定の空間を形成する気室部と、気室部及び周方向溝に連通する狭窄溝部とを有するヘルムホルツ型共鳴器がタイヤ周方向に沿って延びるリブ状陸部に設けられたタイヤが知られている（例えば、特許文献１）。 In order to reduce the air columnar resonance noise formed by the circumferential groove extending along the tire circumferential direction and the road surface among the tire noise, an air chamber portion that forms a certain space by contacting the tread with the road surface; A tire is known in which a Helmholtz resonator having an air chamber portion and a constricted groove portion communicating with a circumferential groove is provided in a rib-like land portion extending along the tire circumferential direction (for example, Patent Document 1).

特開２００８−１７９２８９号公報（第４−５頁、第３図）JP 2008-179289 A (page 4-5, FIG. 3)

しかしながら、上述した従来のタイヤには、次のような問題があった。すなわち、リブ状陸部に設けられたヘルムホルツ型共鳴器、具体的には気室部が小石などをかみ込む、いわゆる「石かみ」が起き易く、タイヤ騒音の増大原因となる。結局、気柱管共鳴音の低減に配慮したトレッドパターンであるにもかかわらず、タイヤ騒音を効果的に低減できない問題があった。勿論、気室部のサイズを大きくすれば、石かみは減少するが、気柱管共鳴音を効果的に低減できない別の問題を惹起する。 However, the conventional tire described above has the following problems. That is, a Helmholtz resonator provided in the rib-like land portion, specifically, a so-called “stone bite” in which the air chamber portion bites pebbles or the like easily occurs, which causes an increase in tire noise. Eventually, there was a problem that the tire noise could not be effectively reduced despite the tread pattern taking into account the reduction of air columnar resonance noise. Of course, if the size of the air chamber portion is increased, the stone bite is reduced, but another problem that the air columnar resonance noise cannot be effectively reduced is caused.

そこで、本発明は、路面と接触することによって一定の空間を形成する気室部と、気室部及び周方向溝に連通する狭窄溝部とを有するヘルムホルツ型共鳴器が設けられる場合において、小石などのかみ込みを防止しつつ、気柱管共鳴音を効果的に低減したタイヤの提供を目的とする。 In view of this, the present invention provides a Helmholtz-type resonator having an air chamber portion that forms a certain space by contacting with the road surface, and a narrowed groove portion that communicates with the air chamber portion and the circumferential groove. An object of the present invention is to provide a tire that effectively reduces air column resonance noise while preventing biting.

上述した課題を解決するため、本発明は、次のような特徴を有している。まず、本発明の第１の特徴は、タイヤ周方向（方向Ｄ１）に沿って延びる周方向溝（例えば、周方向溝１１）に隣接し、タイヤ周方向に沿って延びるリブ状陸部（リブ状陸部１１０）を備えるタイヤ（空気入りタイヤ１０）であって、タイヤ径方向内側に向かって凹んだ凹部分（凹部分１３１）がタイヤ周方向に沿って所定の間隔（間隔Ｐ）で繰り返す気室部（例えば、気室部１３０Ａ）と、前記凹部分に連通する狭窄溝部（狭窄溝部１２１）とが前記リブ状陸部に形成され、前記気室部の底面（底面１３２）から前記リブ状陸部が路面（路面ＲＳ）と接地する接地面（例えば、陸部１２０Ａ）までの高さ（高さＨ）は、タイヤ周方向に沿って変化し、前記狭窄溝部と前記路面とによって形成される空間の容積は、前記凹部分と前記路面とによって形成される空間の容積よりも小さく、前記狭窄溝部の一端（端部１２１ａ）は、前記気室部と前記路面とによって形成される閉空間に連通するとともに、前記狭窄溝部の他端（端部１２１ｂ）は、前記周方向溝に連通し、互いに隣接する２つの前記最高位置間の前記底面と、前記陸部に接する路面とによって前記気室部が形成されており、前記気室部は、第１気室部と、トレッド幅方向において前記第１気室部と異なる位置に設けられる第２気室部とを含み、前記第２気室部の底面の形状は、前記第１気室部の底面の形状と略同一であり、前記第１気室部と前記第２気室部とは、前記凹部分が前記所定の間隔で繰り返し、前記第１気室部の底面の前記最高位置と、前記第２気室部の底面の前記最高位置とは、タイヤ周方向において、前記所定の間隔の半位相ずれていることを要旨とする。 In order to solve the above-described problems, the present invention has the following features. First, the first feature of the present invention is that a rib-like land portion (rib) is adjacent to a circumferential groove (for example, circumferential groove 11) extending along the tire circumferential direction (direction D1) and extending along the tire circumferential direction. Tire (pneumatic tire 10) having a land portion 110), and a concave portion (a concave portion 131) that is recessed inward in the tire radial direction repeats at a predetermined interval (interval P) along the tire circumferential direction. An air chamber portion (for example, air chamber portion 130A) and a constricted groove portion (constricted groove portion 121) communicating with the concave portion are formed in the rib-shaped land portion, and the rib is formed from the bottom surface (bottom surface 132) of the air chamber portion. The height (height H) to the contact surface (for example, the land portion 120A) where the land portion contacts the road surface (road surface RS) varies along the tire circumferential direction and is formed by the narrowed groove portion and the road surface. The volume of the space to be made is in the concave portion and the road surface. The one end (end portion 121a) of the narrowed groove portion communicates with the closed space formed by the air chamber portion and the road surface, and the other end of the narrowed groove portion ( The end portion 121b) communicates with the circumferential groove, and the air chamber portion is formed by the bottom surface between two adjacent highest positions and the road surface in contact with the land portion, and the air chamber portion Includes a first air chamber portion and a second air chamber portion provided at a position different from the first air chamber portion in the tread width direction, and the shape of the bottom surface of the second air chamber portion is the first air chamber portion. The shape of the bottom surface of the chamber portion is substantially the same, and the first air chamber portion and the second air chamber portion are such that the concave portion repeats at the predetermined interval, and the highest of the bottom surface of the first air chamber portion. The position and the highest position of the bottom surface of the second air chamber portion are the front in the tire circumferential direction. And summarized in that are shifted half a phase of the predetermined interval.

本発明の第２の特徴は、本発明の第１の特徴に係り、前記第１気室部と前記第２気室部とは、同一の前記リブ状陸部に設けられることを要旨とする。 A second feature of the present invention relates to the first feature of the present invention, and is summarized in that the first air chamber portion and the second air chamber portion are provided in the same rib-shaped land portion. .

本発明の第３の特徴は、本発明の第１又は２の特徴に係り、前記リブ状陸部のタイヤ周方向に沿った縁部分のうち、少なくとも前記狭窄溝部と連通した部分には、面取り部（面取り部１５０）が形成され、前記面取り部は、トレッド幅方向及びタイヤ径方向に沿った断面において、曲線によって構成されることを要旨とする。 A third feature of the present invention is related to the first or second feature of the present invention, wherein at least a portion communicating with the narrowed groove portion of the rib-like land portion along the tire circumferential direction is chamfered. The chamfered portion is formed by a curved line in a cross section along the tread width direction and the tire radial direction.

本発明の第４の特徴は、本発明の第１の特徴に係り、前記気室部の底面は、タイヤ周方向と異なる方向に沿って前記路面と線接触することを要旨とする。 A fourth feature of the present invention relates to the first feature of the present invention, and is summarized in that a bottom surface of the air chamber portion is in line contact with the road surface along a direction different from a tire circumferential direction.

本発明の第５の特徴は、本発明の第１乃至第４の特徴に係り、前記狭窄溝部の一端は、前記底面の位置が最も低い最低位置（最低位置１３２ｂ）において、前記凹部分に連通することを要旨とする。 A fifth feature of the present invention relates to the first to fourth features of the present invention, wherein one end of the narrowed groove portion communicates with the concave portion at a lowest position (lowest position 132b) where the bottom surface is lowest. The gist is to do.

本発明の第６の特徴は、本発明の第１乃至第５の特徴に係り、前記気室部の底面は、タイヤ周方向に沿った断面視において、円弧を形成するアーチ状を繰り返すことを要旨とする。 A sixth feature of the present invention relates to the first to fifth features of the present invention, wherein the bottom surface of the air chamber portion repeats an arch shape forming an arc in a cross-sectional view along the tire circumferential direction. The gist.

本発明の第７の特徴は、本発明の第６の特徴に係り、前記円弧の中心は、前記底面よりもタイヤ径方向内側に位置することを要旨とする。 A seventh feature of the present invention relates to the sixth feature of the present invention, and is summarized in that the center of the arc is located on the inner side in the tire radial direction than the bottom surface.

本発明の第８の特徴は、本発明の第１乃至第５の特徴に係り、前記気室部の底面は、タイヤ周方向に沿った断面視において正弦波の形状であることを要旨とする。 An eighth feature of the present invention relates to the first to fifth features of the present invention, and is summarized in that the bottom surface of the air chamber portion has a sinusoidal shape in a cross-sectional view along the tire circumferential direction. .

本発明の第９の特徴は、本発明の第１乃至８の特徴に係り、前記気室部の前記底面の位置が最も高い最高位置は、トレッド面視において、トレッド幅方向に傾斜することを要旨とする。 A ninth feature of the present invention relates to the first to eighth features of the present invention, wherein the highest position where the position of the bottom surface of the air chamber portion is highest is inclined in the tread width direction in a tread surface view. The gist.

本発明の第１０の特徴は、本発明の第１乃至９の特徴に係り、前記気室部の前記底面の位置が最も低い最低位置は、トレッド面視において、トレッド幅方向に傾斜することを要旨とする。 A tenth feature of the present invention relates to the first to ninth features of the present invention, wherein the lowest position where the bottom surface position of the air chamber portion is lowest is inclined in the tread width direction in the tread surface view. The gist.

本発明の第１１の特徴は、本発明の第１乃至１０の特徴に係り、前記リブ状陸部と前記気室部との間には、タイヤ周方向に沿って延びるとともに、少なくとも一端が前記凹部分に連通する周方向サイプが形成されることを要旨とする。 An eleventh feature of the present invention relates to the first to tenth features of the present invention, wherein the rib-shaped land portion and the air chamber portion extend along the tire circumferential direction, and at least one end thereof is the above-mentioned feature. The gist is that a circumferential sipe communicating with the concave portion is formed.

本発明の特徴によれば、路面と接触することによって一定の空間を形成する気室部と、気室部及び周方向溝に連通する狭窄溝部とを有するヘルムホルツ型共鳴器が設けられる場合において、小石などのかみ込みを防止しつつ、気柱管共鳴音を効果的に低減したタイヤを提供できる。 According to a feature of the present invention, in the case where a Helmholtz resonator having an air chamber portion that forms a certain space by contacting with the road surface and a narrowed groove portion that communicates with the air chamber portion and the circumferential groove is provided, It is possible to provide a tire that effectively reduces air columnar resonance noise while preventing biting of pebbles and the like.

第１実施形態に係る空気入りタイヤ１０の一部正面図である。1 is a partial front view of a pneumatic tire 10 according to a first embodiment. 第１実施形態に係る陸部１２０Ａの部分を省略したリブ状陸部１１０の一部斜視図である。It is a partial perspective view of the rib-shaped land part 110 which abbreviate | omitted the part of the land part 120A which concerns on 1st Embodiment. 第１実施形態に係るヘルムホルツ型共鳴器Ｒ１のトレッド幅方向視における形状を示す図である。It is a figure which shows the shape in the tread width direction view of Helmholtz type resonator R1 which concerns on 1st Embodiment. 第１実施形態に係るヘルムホルツ型共鳴器Ｒ１のトレッド平面視における形状を示す図である。It is a figure which shows the shape in the tread planar view of Helmholtz type resonator R1 which concerns on 1st Embodiment. 第１実施形態に係るリブ状陸部２１０の一部を省略したリブ状陸部２１０及びリブ状陸部２４０の一部斜視図である。It is a partial perspective view of the rib-like land portion 210 and the rib-like land portion 240 in which a part of the rib-like land portion 210 according to the first embodiment is omitted. 第１実施形態に係る図９に示したＦ１０−Ｆ１０線に沿った気室部２２０の断面図である。It is sectional drawing of the air chamber part 220 along the F10-F10 line shown in FIG. 9 which concerns on 1st Embodiment. 第１実施形態に係るヘルムホルツ型共鳴器Ｒ２のトレッド幅方向視における形状を示す図である。It is a figure which shows the shape in the tread width direction view of Helmholtz type resonator R2 which concerns on 1st Embodiment. 第１実施形態に係るリブ状陸部２１０及びリブ状陸部２４０の一部拡大平面図である。It is a partially expanded plan view of the rib-like land portion 210 and the rib-like land portion 240 according to the first embodiment. 第２実施形態に係る空気入りタイヤ１０Ａの一部正面図である。It is a partial front view of a pneumatic tire 10A according to the second embodiment. 本発明の変更例１に係る気室部を示す図である。It is a figure which shows the air chamber part which concerns on the example 1 of a change of this invention. 本発明の変更例２に係る気室部を示す図である。It is a figure which shows the air chamber part which concerns on the modification 2 of this invention. 本発明の変更例３に係る気室部を示す図である。It is a figure which shows the air chamber part which concerns on the modification 3 of this invention. 本発明の変更例４に係るリブ状陸部１１０Ａの一部を示す図である。It is a figure which shows a part of 110 A of rib-shaped land parts which concern on the modification 4 of this invention. 本発明の変更例５に係る気室部１３０Ａ及び気室部１３０Ｂのトレッド平面視における形状を示す図である。It is a figure which shows the shape in tread planar view of 130 A of air chamber parts and 130 C of air chamber parts which concern on the modification 5 of this invention. 本発明の変更例６に係るリブ状陸部１１０Ｂの一部を示す図である。It is a figure which shows a part of rib-shaped land part 110B which concerns on the modification 6 of this invention.

次に、本発明に係るタイヤの実施形態について、図面を参照しながら説明する。具体的には、第１実施形態、第２実施形態、変更例、及びその他の実施形態について説明する。 Next, an embodiment of a tire according to the present invention will be described with reference to the drawings. Specifically, the first embodiment, the second embodiment, modified examples, and other embodiments will be described.

なお、以下の図面の記載において、同一または類似の部分には、同一または類似の符号を付している。但し、図面は模式的なものであり、各寸法の比率などは現実のものとは異なることに留意されたい。 In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions are different from actual ones.

したがって、具体的な寸法などは以下の説明を参酌して判断すべきである。また、図面相互間においても互いの寸法の関係や比率が異なる部分が含まれている場合がある。 Accordingly, specific dimensions and the like should be determined in consideration of the following description. In addition, there may be a case where the dimensional relationships and ratios are different between the drawings.

［第１実施形態］
以下において、第１実施形態に係る空気入りタイヤ１０について説明する。具体的には、（１）タイヤの全体概略構成、（２）リブ状陸部の形状、及び（３）作用・効果について説明する。 [First Embodiment]
Hereinafter, the pneumatic tire 10 according to the first embodiment will be described. Specifically, (1) the overall schematic configuration of the tire, (2) the shape of the rib-like land portion, and (3) actions and effects will be described.

（１）タイヤの全体概略構成
図１は、空気入りタイヤ１０の一部正面図である。なお、第１実施形態に係る空気入りタイヤ１０の回転方向については、図１の方向ＤＲである。 (1) Overall Schematic Configuration of Tire FIG. 1 is a partial front view of a pneumatic tire 10. In addition, about the rotation direction of the pneumatic tire 10 which concerns on 1st Embodiment, it is the direction DR of FIG.

空気入りタイヤ１０には、複数の周方向溝が形成される。また、空気入りタイヤ１０には、当該周方向溝によって区画され、タイヤ周方向（図１の方向Ｄ１）に沿って延びる複数のリブ状陸部が設けられる。空気入りタイヤ１０は、気柱管共鳴音などのタイヤ騒音の低減に配慮されたタイヤであり、高い静粛性が要求される乗用自動車などに装着される。なお、空気入りタイヤ１０には、空気ではなく、窒素ガスなどの不活性ガスを充填してもよい。 A plurality of circumferential grooves are formed in the pneumatic tire 10. The pneumatic tire 10 is provided with a plurality of rib-like land portions that are partitioned by the circumferential groove and extend along the tire circumferential direction (direction D1 in FIG. 1). The pneumatic tire 10 is a tire that is designed to reduce tire noise such as air columnar resonance and is mounted on a passenger car or the like that requires high silence. The pneumatic tire 10 may be filled with an inert gas such as nitrogen gas instead of air.

具体的には、空気入りタイヤ１０には、周方向溝１１，１２，２１及び２２が形成される。周方向溝１１，１２，２１及び２２は、タイヤ周方向に沿って延びる。 Specifically, circumferential grooves 11, 12, 21 and 22 are formed in the pneumatic tire 10. The circumferential grooves 11, 12, 21, and 22 extend along the tire circumferential direction.

周方向溝１１と周方向溝１２との間には、リブ状陸部１１０が設けられる。すなわち、リブ状陸部１１０は、周方向溝１１及び周方向溝１２に隣接し、タイヤ周方向に沿って延びる。 A rib-shaped land portion 110 is provided between the circumferential groove 11 and the circumferential groove 12. That is, the rib-like land portion 110 is adjacent to the circumferential groove 11 and the circumferential groove 12 and extends along the tire circumferential direction.

周方向溝１２と周方向溝２１との間には、リブ状陸部２１０が設けられる。また、周方向溝２１と周方向溝２２との間には、リブ状陸部２４０が設けられる。リブ状陸部２１０及びリブ状陸部２４０もリブ状陸部１１０と同様にタイヤ周方向に沿って延びる。 A rib-shaped land portion 210 is provided between the circumferential groove 12 and the circumferential groove 21. A rib-like land portion 240 is provided between the circumferential groove 21 and the circumferential groove 22. The rib-shaped land portion 210 and the rib-shaped land portion 240 also extend along the tire circumferential direction in the same manner as the rib-shaped land portion 110.

リブ状陸部１１０には、タイヤ径方向内側に向かって凹んだ凹部分がタイヤ周方向に沿って所定の間隔で繰り返す気室部１３０Ａ及び気室部１３０Ｂ（図２参照）が設けられる。 The rib-like land portion 110 is provided with an air chamber portion 130A and an air chamber portion 130B (see FIG. 2) in which concave portions that are recessed inward in the tire radial direction are repeated at predetermined intervals along the tire circumferential direction.

リブ状陸部２１０には、気室部２２０（図５参照）がタイヤ周方向に沿って複数設けられる。同様に、リブ状陸部２４０には、気室部２５０（図５参照）がタイヤ周方向に沿って複数設けられる。 The rib-like land portion 210 is provided with a plurality of air chamber portions 220 (see FIG. 5) along the tire circumferential direction. Similarly, the rib-like land portion 240 is provided with a plurality of air chamber portions 250 (see FIG. 5) along the tire circumferential direction.

周方向溝１１，２２のトレッド幅方向（図１の方向Ｄ２）外側には、リブ状陸部３１０，３２０が設けられる。リブ状陸部３１０には、トレッド幅方向外側端がトレッド幅方向内側端よりもタイヤ回転方向（方向ＤＲ）の後方に位置する傾斜細溝３１１が複数設けられる。リブ状陸部３２０には、トレッド幅方向外側端がトレッド幅方向内側端よりもタイヤ回転方向（方向ＤＲ）の前方に位置する傾斜細溝３２１が複数設けられる。 On the outer side of the circumferential grooves 11 and 22 in the tread width direction (direction D2 in FIG. 1), rib-like land portions 310 and 320 are provided. The rib-shaped land portion 310 is provided with a plurality of inclined narrow grooves 311 whose outer ends in the tread width direction are located behind the inner ends in the tread width direction in the tire rotation direction (direction DR). The rib-shaped land portion 320 is provided with a plurality of inclined narrow grooves 321 whose outer ends in the tread width direction are positioned in front of the inner ends in the tread width direction in the tire rotation direction (direction DR).

つまり、第１実施形態に係る空気入りタイヤ１０、右上がりパターンを有している（図１参照）。この場合、空気入りタイヤ１０のバランスを考慮して、不図示のベルト層を構成するコードは、トレッド面視においてトレッドパターンとは逆側に傾斜している（すなわち、左上がりコードである）ことが好ましい。 That is, the pneumatic tire 10 according to the first embodiment has a right-up pattern (see FIG. 1). In this case, in consideration of the balance of the pneumatic tire 10, the cord constituting the belt layer (not shown) is inclined to the opposite side of the tread pattern in the tread surface view (that is, the cord is a left-up cord). Is preferred.

（２）リブ状陸部の形状
次に、リブ状陸部の形状について説明する。具体的には、リブ状陸部１１０及びリブ状陸部２１０，２４０の形状について説明する。 (2) Shape of rib-like land portion Next, the shape of the rib-like land portion will be described. Specifically, the shape of the rib-like land portion 110 and the rib-like land portions 210 and 240 will be described.

（２．１）リブ状陸部１１０
図２は、陸部１２０Ａの部分を省略したリブ状陸部１１０の一部斜視図である。図２に示すように、リブ状陸部１１０は、陸部１２０Ａ、陸部１２０Ｂ及び陸部１４０を有する。陸部１２０Ａ、陸部１２０Ｂ及び陸部１４０は、空気入りタイヤ１０が転動することによって路面ＲＳ（図２において不図示、図３参照）と接地する。すなわち、陸部１２０Ａ、陸部１２０Ｂ及び陸部１４０は、路面ＲＳと接地する空気入りタイヤ１０の接地面を構成する。 (2.1) Rib-shaped land portion 110
FIG. 2 is a partial perspective view of the rib-like land portion 110 from which the land portion 120A is omitted. As shown in FIG. 2, the rib-shaped land portion 110 includes a land portion 120 A, a land portion 120 B, and a land portion 140. The land portion 120A, the land portion 120B, and the land portion 140 are in contact with the road surface RS (not shown in FIG. 2, refer to FIG. 3) when the pneumatic tire 10 rolls. That is, the land portion 120A, the land portion 120B, and the land portion 140 constitute a contact surface of the pneumatic tire 10 that contacts the road surface RS.

陸部１２０Ａ及び陸部１２０Ｂは、リブ状陸部１１０のトレッド幅方向（方向Ｄ２）における両端に設けられる。陸部１２０Ａは、周方向溝１１に隣接する。陸部１２０Ｂは、周方向溝１２に隣接する。 The land portion 120A and the land portion 120B are provided at both ends of the rib-like land portion 110 in the tread width direction (direction D2). The land portion 120 A is adjacent to the circumferential groove 11. The land portion 120 B is adjacent to the circumferential groove 12.

また、リブ状陸部１１０には、気室部１３０Ａ及び気室部１３０Ｂが設けられる。気室部１３０Ａは、陸部１２０Ａと陸部１４０との間に設けられる。気室部１３０Ａには、タイヤ径方向内側に向かって凹んだ凹部分１３１が形成される。 The rib-shaped land portion 110 is provided with an air chamber portion 130A and an air chamber portion 130B. The air chamber part 130A is provided between the land part 120A and the land part 140. The air chamber portion 130A is formed with a recessed portion 131 that is recessed toward the inside in the tire radial direction.

図２に示すように、凹部分１３１は、タイヤ周方向に沿って間隔Ｐ（所定の間隔）で繰り返される。 As shown in FIG. 2, the recessed portion 131 is repeated at intervals P (predetermined intervals) along the tire circumferential direction.

気室部１３０Ａと気室部１３０Ｂとは、同一のリブ状陸部（リブ状陸部１１０）に設けられるが、気室部１３０Ｂは、トレッド幅方向（方向Ｄ２）において気室部１３０Ａと異なる位置に設けられる。具体的には、気室部１３０Ｂは、陸部１２０Ｂと陸部１４０との間に設けられる。気室部１３０Ｂの形状は、気室部１３０Ａと同一である。つまり、気室部１３０Ａと気室部１３０Ｂとは、凹部分１３１が間隔Ｐで繰り返される。第１実施形態において、気室部１３０Ａは、第１気室部を構成し、気室部１３０Ｂは、第２気室部を構成する。 The air chamber portion 130A and the air chamber portion 130B are provided in the same rib-shaped land portion (rib-shaped land portion 110), but the air chamber portion 130B is different from the air chamber portion 130A in the tread width direction (direction D2). Provided in position. Specifically, the air chamber part 130 B is provided between the land part 120 B and the land part 140. The shape of the air chamber portion 130B is the same as that of the air chamber portion 130A. That is, in the air chamber portion 130A and the air chamber portion 130B, the recessed portion 131 is repeated at the interval P. In the first embodiment, the air chamber portion 130A constitutes a first air chamber portion, and the air chamber portion 130B constitutes a second air chamber portion.

気室部１３０Ａ及び気室部１３０Ｂの形状は同一であるため、以下、気室部１３０Ａの形状について主に説明する。図２に示すように、気室部１３０Ａの底面１３２は、タイヤ周方向に沿った断面視において、円弧を形成するアーチ状を繰り返す。つまり、気室部１３０Ａの底面１３２から接地面（例えば、路面ＲＳと接地する陸部１２０Ａの表面）までの高さＨは、タイヤ周方向に沿って変化する。底面１３２の円弧の中心ＣＴ１は、底面１３２よりもタイヤ径方向内側に位置する。 Since the shape of the air chamber portion 130A and the air chamber portion 130B are the same, the shape of the air chamber portion 130A will be mainly described below. As shown in FIG. 2, the bottom surface 132 of the air chamber portion 130 A repeats an arch shape that forms an arc in a cross-sectional view along the tire circumferential direction. That is, the height H from the bottom surface 132 of the air chamber portion 130A to the ground contact surface (for example, the surface of the land portion 120A that contacts the road surface RS) varies along the tire circumferential direction. The center CT1 of the arc of the bottom surface 132 is located on the inner side in the tire radial direction than the bottom surface 132.

底面１３２は、接地面までの高さが最も高い最高位置１３２ａにおいて路面ＲＳと接触する。具体的には、底面１３２は、タイヤ周方向と異なる方向に沿って路面ＲＳと線接触する。つまり、底面１３２は、路面ＲＳと接触する底面１３２のタイヤ周方向に沿った幅が極力狭くなるような形状を有する。 The bottom surface 132 contacts the road surface RS at the highest position 132a having the highest height to the ground contact surface. Specifically, the bottom surface 132 is in line contact with the road surface RS along a direction different from the tire circumferential direction. That is, the bottom surface 132 has such a shape that the width along the tire circumferential direction of the bottom surface 132 in contact with the road surface RS is as small as possible.

なお、底面１３２の最高位置１３２ａは、トレッド面視において、トレッド幅方向（方向Ｄ２）に沿っている。すなわち、最高位置１３２ａのトレッド幅方向における外側端１３２ｅ１と、最高位置１３２ａのトレッド幅方向における内側端１３２ｅ２とは、トレッド幅方向に対して略同一である（図２及び後述する図４参照）。 The highest position 132a of the bottom surface 132 is along the tread width direction (direction D2) in the tread surface view. That is, the outer end 132e1 in the tread width direction of the highest position 132a and the inner end 132e2 in the tread width direction of the highest position 132a are substantially the same in the tread width direction (see FIG. 2 and FIG. 4 described later).

気室部１３０Ｂの底面の形状は、底面１３２の形状と同一であるが、気室部１３０Ａの底面１３２の最高位置１３２ａと、気室部１３０Ｂの底面の最高位置１３２ａとは、タイヤ周方向において、間隔Ｐの半位相ずれている。 The shape of the bottom surface of the air chamber portion 130B is the same as the shape of the bottom surface 132, but the highest position 132a of the bottom surface 132 of the air chamber portion 130A and the highest position 132a of the bottom surface of the air chamber portion 130B are in the tire circumferential direction. , The phase P is shifted by a half phase.

また、陸部１２０Ａには、狭窄溝部１２１及び細溝１２２が形成される。狭窄溝部１２１及び細溝１２２は、溝幅が数ｍｍ程度の細溝である。狭窄溝部１２１は、凹部分１３１に連通する。狭窄溝部１２１と路面ＲＳとによって形成される空間の容積は、凹部分１３１と路面とによって形成される空間よりも容積が小さい。なお、狭窄溝部１２１及び細溝１２２は、トレッド幅方向外側端がトレッド幅方向内側端よりもタイヤ回転方向（方向ＤＲ）の後方に位置する。 Moreover, the narrow groove part 121 and the narrow groove 122 are formed in the land part 120A. The narrowed groove 121 and the narrow groove 122 are narrow grooves having a groove width of about several mm. The narrowed groove 121 communicates with the concave portion 131. The volume of the space formed by the narrowed groove 121 and the road surface RS is smaller than the space formed by the concave portion 131 and the road surface. In addition, the narrow groove part 121 and the narrow groove 122 have a tread width direction outer side end located behind the tread width direction inner side end in the tire rotation direction (direction DR).

図３及び図４は、空気入りタイヤ１０と路面ＲＳとによって形成されるヘルムホルツ型共鳴器Ｒ１の形状を示す。具体的には、図３は、トレッド幅方向視におけるヘルムホルツ型共鳴器Ｒ１の形状を示す。図４は、トレッド平面視におけるヘルムホルツ型共鳴器Ｒ１の形状を示す。図３及び図４に示すように、狭窄溝部１２１と、凹部分１３１を有する気室部１３０Ａとは、ヘルムホルツ型共鳴器Ｒ１を構成する。 3 and 4 show the shape of the Helmholtz resonator R1 formed by the pneumatic tire 10 and the road surface RS. Specifically, FIG. 3 shows the shape of the Helmholtz resonator R1 when viewed in the tread width direction. FIG. 4 shows the shape of the Helmholtz resonator R1 in the tread plan view. As shown in FIGS. 3 and 4, the narrowed groove 121 and the air chamber 130 A having the recess 131 constitute a Helmholtz resonator R 1.

上述したように、気室部１３０Ａの底面１３２から接地面までの高さＨは、タイヤ周方向に沿って変化するが、間隔Ｐ毎に繰り返される複数の最高位置１３２ａが路面ＲＳと接するため、狭窄溝部１２１に連通する気室が形成される。つまり、互いに隣接する２つの最高位置１３２ａ間の底面１３２と、陸部１２０Ａ及び陸部１４０に接する路面ＲＳとによって、ヘルムホルツ型共鳴器Ｒ１用の気室が形成される。なお、ヘルムホルツ型共鳴器Ｒ１を用いた気柱管共鳴音の低減方法については、本明細書に記載した先行技術文献など開示されているため、ここでの説明は省略する。 As described above, the height H from the bottom surface 132 of the air chamber portion 130A to the ground contact surface varies along the tire circumferential direction, but since the plurality of highest positions 132a repeated at every interval P are in contact with the road surface RS, An air chamber communicating with the narrowed groove 121 is formed. That is, an air chamber for the Helmholtz resonator R1 is formed by the bottom surface 132 between the two highest positions 132a adjacent to each other and the road surface RS in contact with the land portion 120A and the land portion 140. The method for reducing the air columnar resonance using the Helmholtz resonator R1 has been disclosed in the prior art document described in the present specification, and will not be described here.

図２に示すように、狭窄溝部１２１の一端（端部１２１ａ）は、気室部１３０Ａと路面ＲＳとによって形成される閉空間に連通する。具体的には、端部１２１ａは、凹部分１３１と、凹部分１３１のタイヤ周方向における両端に形成される最高位置１３２ａと、路面ＲＳとによって形成される閉空間に連通する。 As shown in FIG. 2, one end (end portion 121a) of the narrowed groove 121 communicates with a closed space formed by the air chamber portion 130A and the road surface RS. Specifically, the end 121a communicates with a closed space formed by the recessed portion 131, the highest positions 132a formed at both ends of the recessed portion 131 in the tire circumferential direction, and the road surface RS.

一方、狭窄溝部１２１の他端（端部１２１ｂ）は、周方向溝１１に連通する。第１実施形態では、端部１２１ａは、底面１３２の位置が最も低い最低位置１３２ｂにおいて、凹部分１３１に連通する。このため、ヘルムホルツ型共鳴器Ｒ１は、一端のみが開口し、他端などは閉口している。 On the other hand, the other end (end portion 121 b) of the narrowed groove 121 communicates with the circumferential groove 11. In the first embodiment, the end 121a communicates with the concave portion 131 at the lowest position 132b where the bottom surface 132 is lowest. For this reason, only one end of the Helmholtz resonator R1 is open, and the other end is closed.

なお、底面１３２の最低位置１３２ｂは、トレッド面視において、トレッド幅方向（方向Ｄ２）に沿っている。すなわち、最低位置１３２ｂのトレッド幅方向における外側端１３２ｅ３と、最低位置１３２ｂのトレッド幅方向における内側端１３２ｅ４とは、トレッド幅方向に対して略同一である（図２及び図４参照）。 The lowest position 132b of the bottom surface 132 is along the tread width direction (direction D2) in the tread surface view. That is, the outer end 132e3 in the tread width direction of the lowest position 132b and the inner end 132e4 in the tread width direction of the lowest position 132b are substantially the same in the tread width direction (see FIGS. 2 and 4).

細溝１２２は、周方向溝１１にのみ連通する。つまり、細溝１２２は、凹部分１３１には連通していない。このため、細溝１２２は、ヘルムホルツ型共鳴器Ｒ１の構成要素とはなっていない。 The narrow groove 122 communicates only with the circumferential groove 11. That is, the narrow groove 122 does not communicate with the concave portion 131. For this reason, the narrow groove 122 is not a component of the Helmholtz resonator R1.

（２．２）リブ状陸部２１０，２４０
図５は、リブ状陸部２１０の一部を省略したリブ状陸部２１０及びリブ状陸部２４０の一部斜視図である。図５に示すように、リブ状陸部２１０には、路面ＲＳ（図７参照）と接地する陸部２１１、及び複数の気室部２２０が設けられる。複数の気室部２２０は、タイヤ周方向に沿って設けられる。リブ状陸部２４０には、陸部２１１と同一形状の陸部２４１、及び気室部２２０と同一形状の気室部２５０が設けられる。リブ状陸部２４０は、トレッド幅方向においてリブ状陸部２１０と異なる位置に設けられる。第１実施形態において、リブ状陸部２１０は、第１リブ状陸部を構成し、リブ状陸部２４０は、第２リブ状陸部を構成する。 (2.2) Rib-shaped land portions 210 and 240
FIG. 5 is a partial perspective view of the rib-like land portion 210 and the rib-like land portion 240 from which a part of the rib-like land portion 210 is omitted. As shown in FIG. 5, the rib-shaped land portion 210 is provided with a land portion 211 that contacts the road surface RS (see FIG. 7) and a plurality of air chamber portions 220. The plurality of air chamber portions 220 are provided along the tire circumferential direction. The rib-like land portion 240 is provided with a land portion 241 having the same shape as the land portion 211 and an air chamber portion 250 having the same shape as the air chamber portion 220. The rib-like land portion 240 is provided at a position different from the rib-like land portion 210 in the tread width direction. In the first embodiment, the rib-like land portion 210 constitutes a first rib-like land portion, and the rib-like land portion 240 constitutes a second rib-like land portion.

気室部２２０及び気室部２５０の形状は同一であるため、以下、気室部２２０の形状について主に説明する。図６は、図５に示したＦ６−Ｆ６線に沿った気室部２２０の断面図である。図５及び図６に示すように、気室部２２０は、タイヤ径方向内側に向かって凹んだ凹部分２２１を有する。 Since the air chamber part 220 and the air chamber part 250 have the same shape, the shape of the air chamber part 220 will be mainly described below. 6 is a cross-sectional view of the air chamber 220 taken along line F6-F6 shown in FIG. As shown in FIGS. 5 and 6, the air chamber 220 has a recessed portion 221 that is recessed toward the inside in the tire radial direction.

陸部２１１が路面と接地する接地面（路面ＲＳと接地する陸部２１１の表面）を基準とする凹部分２２１の深さＤＰ１は、タイヤ周方向における気室部２２０の一端（タイヤ回転方向（方向ＤＲ）の後方に位置する端部２２０ｂ、図５参照）において気室部２２０の他端（タイヤ回転方向の前方に位置する端部２２０ａ、図５参照）よりも深い。また、凹部分２２１の底面２２２から接地面までの高さは、タイヤ周方向に沿って変化している。 The depth DP1 of the concave portion 221 with reference to the contact surface on which the land portion 211 contacts the road surface (the surface of the land portion 211 that contacts the road surface RS) is one end of the air chamber 220 in the tire circumferential direction (the tire rotation direction ( In the end portion 220b positioned rearward in the direction DR) (see FIG. 5), the air chamber portion 220 is deeper than the other end (the end portion 220a positioned forward in the tire rotation direction, see FIG. 5). Further, the height from the bottom surface 222 of the concave portion 221 to the ground contact surface changes along the tire circumferential direction.

凹部分２２１の底面２２２は、タイヤ周方向に沿った断面視において、曲線状である曲線部分２２３を有する。曲線部分２２３に沿った円弧の中心ＣＴ２は、底面２２２よりもタイヤ径方向内側に位置する。なお、曲線部分２２３は、複数の円弧によって構成されてもよい。この場合、中心ＣＴ２は、当該複数の円弧によって形成された曲線に近似したひとつの円弧の中心とする。 The bottom surface 222 of the concave portion 221 has a curved portion 223 that is curved in a cross-sectional view along the tire circumferential direction. A center CT2 of the arc along the curved portion 223 is located on the inner side in the tire radial direction than the bottom surface 222. The curved portion 223 may be configured by a plurality of arcs. In this case, the center CT2 is the center of one arc approximated to a curve formed by the plurality of arcs.

また、底面２２２は、タイヤ周方向に沿った断面視において直線状である直線状部分２２４を有する。直線状部分２２４は、気室部２２０の端部２２０ｂ（図５参照）側に形成される。直線状部分２２４の一端（端部２２４ａ）は、曲線部分２２３の端部２２３ｂに連なるとともに、直線状部分２２４の他端（端部２２４ｂ）は、陸部２１１が路面と接地する接地面に連なる。 Further, the bottom surface 222 has a linear portion 224 that is linear in a cross-sectional view along the tire circumferential direction. The straight portion 224 is formed on the end 220b (see FIG. 5) side of the air chamber 220. One end (end portion 224a) of the linear portion 224 is connected to the end portion 223b of the curved portion 223, and the other end (end portion 224b) of the linear portion 224 is connected to a ground plane on which the land portion 211 contacts the road surface. .

気室部２２０には、狭窄溝部２３０が連通する。具体的には、狭窄溝部２３０は、タイヤ周方向における気室部２２０の端部２２０ａに連通する。つまり、狭窄溝部２３０は、気室部２２０と路面ＲＳとによって形成される閉空間に連通する。また、狭窄溝部２３０は、周方向溝２１に連通する。狭窄溝部２３０と路面とによって形成される空間の容積は、凹部分２２１と路面とによって形成される空間の容積よりも小さい。 The narrowed groove portion 230 communicates with the air chamber portion 220. Specifically, the narrowed groove 230 communicates with the end 220a of the air chamber 220 in the tire circumferential direction. That is, the narrowed groove portion 230 communicates with a closed space formed by the air chamber portion 220 and the road surface RS. Further, the narrowed groove portion 230 communicates with the circumferential groove 21. The volume of the space formed by the narrowed groove portion 230 and the road surface is smaller than the volume of the space formed by the concave portion 221 and the road surface.

狭窄溝部２３０は、外溝部２３１と内溝部２３２とによって構成される。外溝部２３１は、周方向溝２１に連通し、気室部２２０の端部２２０ａまで延びる。内溝部２３２は、外溝部２３１に連通し、気室部２２０の端部２２０ｂ、具体的には直線状部分２２４の側方までタイヤ周方向に沿って延びる。第１実施形態において、内溝部２３２は、延在部分を構成する。内溝部２３２は、凹部分２２１と、陸部２１１が路面と接地する接地面との間に形成される。 The narrowed groove portion 230 includes an outer groove portion 231 and an inner groove portion 232. The outer groove portion 231 communicates with the circumferential groove 21 and extends to the end portion 220 a of the air chamber portion 220. The inner groove portion 232 communicates with the outer groove portion 231 and extends along the tire circumferential direction to the end portion 220b of the air chamber portion 220, specifically, to the side of the linear portion 224. In the first embodiment, the inner groove 232 constitutes an extended portion. The inner groove portion 232 is formed between the concave portion 221 and the ground surface on which the land portion 211 contacts the road surface.

図６に示すように、狭窄溝部２３０、具体的には、内溝部２３２の深さＤＰ２は、陸部２１１が路面と接地する接地面からの凹部分２２１の深さＤＰ１よりも深い。 As shown in FIG. 6, the depth DP2 of the narrowed groove portion 230, specifically, the inner groove portion 232 is deeper than the depth DP1 of the concave portion 221 from the ground contact surface where the land portion 211 contacts the road surface.

図７は、空気入りタイヤ１０と路面ＲＳとによって形成されるヘルムホルツ型共鳴器Ｒ２の形状を示す。具体的には、図７は、トレッド幅方向視におけるヘルムホルツ型共鳴器Ｒ２の形状を示す。また、図８の一点鎖線で囲われた領域は、トレッド平面視におけるヘルムホルツ型共鳴器Ｒ２の形状を示す。 FIG. 7 shows the shape of the Helmholtz resonator R2 formed by the pneumatic tire 10 and the road surface RS. Specifically, FIG. 7 shows the shape of the Helmholtz resonator R2 when viewed in the tread width direction. Moreover, the area | region enclosed with the dashed-dotted line of FIG. 8 shows the shape of Helmholtz type | mold resonator R2 in tread planar view.

図７に示すように、凹部分２２１を有する気室部２２０と、外溝部２３１及び内溝部２３２によって構成される狭窄溝部２３０とは、ヘルムホルツ型共鳴器Ｒ２を構成する。ヘルムホルツ型共鳴器Ｒ２は、ヘルムホルツ型共鳴器Ｒ１と同様に、一端のみが開口し、他端などは閉口している。 As shown in FIG. 7, the air chamber portion 220 having the concave portion 221 and the narrowed groove portion 230 formed by the outer groove portion 231 and the inner groove portion 232 constitute a Helmholtz resonator R2. As with the Helmholtz resonator R1, the Helmholtz resonator R2 has only one end opened and the other end closed.

図８は、リブ状陸部２１０及びリブ状陸部２４０の一部拡大平面図である。図８に示すように、気室部２２０は、トレッド面視において、気室部２２０の端部２２０ａから端部２２０ｂに行くに連れてトレッド幅方向の幅Ｗが狭くなる先細り状である。 FIG. 8 is a partially enlarged plan view of the rib-like land portion 210 and the rib-like land portion 240. As shown in FIG. 8, the air chamber portion 220 has a tapered shape in which the width W in the tread width direction becomes narrower from the end portion 220 a of the air chamber portion 220 toward the end portion 220 b in the tread surface view.

また、凹部分２２１のトレッド幅方向（方向Ｄ２）及びタイヤ径方向（図中方向Ｄ３）のに沿った断面積Ｓ（図６参照）は、曲線部分２２３のタイヤ周方向における一端（端部２２３ａ）から他端（端部２２３ｂ）まで略同一である。 Further, the cross-sectional area S (see FIG. 6) along the tread width direction (direction D2) and the tire radial direction (direction D3 in the drawing) of the concave portion 221 is one end (end portion 223a) of the curved portion 223 in the tire circumferential direction. ) To the other end (end portion 223b).

さらに、第１実施形態では、図８に示すように、リブ状陸部２１０に形成される気室部２２０のタイヤ周方向における位置は、リブ状陸部２４０に形成される気室部２５０の位置と異なる。具体的には、リブ状陸部２４０に形成される凹部分の接地面（陸部２４１）からの深さが最も深い位置（端部２２３ｂ）は、タイヤ周方向において、リブ状陸部２１０に形成される凹部分２２１の接地面（陸部２１１）からの深さが最も浅い位置（端部２２３ａ）と略同一である。 Furthermore, in 1st Embodiment, as shown in FIG. 8, the position in the tire circumferential direction of the air chamber part 220 formed in the rib-shaped land part 210 is the position of the air chamber part 250 formed in the rib-shaped land part 240. Different from position. Specifically, the deepest position (end portion 223b) from the ground contact surface (land portion 241) of the concave portion formed in the rib-like land portion 240 is the rib-like land portion 210 in the tire circumferential direction. The depth of the concave portion 221 to be formed from the ground contact surface (land portion 211) is substantially the same as the shallowest position (end portion 223a).

（３）作用・効果
空気入りタイヤ１０によれば、気室部１３０Ａ（１３０Ｂ）の底面１３２から陸部１２０Ａ（１２０Ｂ）が路面ＲＳと接地する接地面までの高さＨは、タイヤ周方向に沿って変化する。つまり、気室部１３０Ａの接地面からの深さがタイヤ周方向に沿って変化するため、気室部１３０Ａが小石などをかみ込んでも、かみ込んだ小石などが空気入りタイヤ１０の転動に伴ってタイヤ周方向に移動させられると、気室部１３０Ａから外れ易くなる。この結果、いわゆる「石かみ」の発生を抑制できる。 (3) Action / Effect According to the pneumatic tire 10, the height H from the bottom surface 132 of the air chamber portion 130A (130B) to the ground contact surface where the land portion 120A (120B) contacts the road surface RS is in the tire circumferential direction. Change along. That is, since the depth of the air chamber portion 130A from the ground contact surface changes along the tire circumferential direction, even if the air chamber portion 130A bites pebbles or the like, the biting pebbles or the like bite the rolling of the pneumatic tire 10. If it is accompanied and moved in the tire circumferential direction, it will be easy to come off from the air chamber portion 130A. As a result, the occurrence of so-called “stone” can be suppressed.

また、狭窄溝部１２１と気室部１３０Ａとによって、具体的には、狭窄溝部１２１と、間隔Ｐ毎に繰り返される複数の最高位置１３２ａが路面ＲＳと接することによって形成される気室によって、吸音したい周波数帯に対応したヘルムホルツ型共鳴器Ｒ１，Ｒ２が構成されるため、周方向溝１１などによる気柱管共鳴音を効果的に低減できる。 Further, it is desired to absorb sound by the narrowed groove 121 and the air chamber 130A, specifically by the air chamber formed by the narrowed groove 121 and the plurality of highest positions 132a repeated at every interval P contacting the road surface RS. Since Helmholtz resonators R1 and R2 corresponding to the frequency band are configured, air columnar resonance noise caused by the circumferential groove 11 and the like can be effectively reduced.

第１実施形態では、気室部１３０Ａの底面１３２は、タイヤ周方向と異なる方向に沿って路面ＲＳと線接触する。このため、気室部１３０Ａの空間を大きくすることが容易であり、吸音したい周波数帯に対応したヘルムホルツ型共鳴器を容易に構成できる。 In the first embodiment, the bottom surface 132 of the air chamber portion 130A is in line contact with the road surface RS along a direction different from the tire circumferential direction. For this reason, it is easy to enlarge the space of the air chamber part 130A, and a Helmholtz resonator corresponding to a frequency band in which sound absorption is desired can be easily configured.

第１実施形態では、狭窄溝部１２１の端部１２１ａは、底面１３２の最低位置１３２ｂにおいて、凹部分１３１に連通する。このため、空気入りタイヤ１０が一定量摩耗した後においてもヘルムホルツ型共鳴器の機能を維持できる。 In the first embodiment, the end 121 a of the narrowed groove 121 communicates with the concave portion 131 at the lowest position 132 b of the bottom surface 132. For this reason, the function of the Helmholtz resonator can be maintained even after the pneumatic tire 10 is worn out by a certain amount.

第１実施形態では、気室部１３０Ａの底面１３２は、アーチ状を繰り返す。また、アーチ状を形成する円弧の中心は、底面１３２よりもタイヤ径方向内側に位置する。このため、ヘルムホルツ型共鳴器の機能を確保しつつ、より効果的に石かみを抑制できる。 In the first embodiment, the bottom surface 132 of the air chamber portion 130A repeats an arch shape. In addition, the center of the arc forming the arch shape is located on the inner side in the tire radial direction than the bottom surface 132. For this reason, it is possible to more effectively suppress the stone bite while ensuring the function of the Helmholtz resonator.

第１実施形態では、気室部１３０Ａの底面１３２の最高位置１３２ａと、気室部１３０Ｂの底面の最高位置１３２ａとは、タイヤ周方向において、間隔Ｐの半位相ずれている。このため、路面ＲＳと接地する空気入りタイヤ１０のトレッド部分の剛性がタイヤ周方向において略均一となる。 In the first embodiment, the highest position 132a of the bottom surface 132 of the air chamber portion 130A and the highest position 132a of the bottom surface of the air chamber portion 130B are shifted by a half phase of the interval P in the tire circumferential direction. For this reason, the rigidity of the tread portion of the pneumatic tire 10 that contacts the road surface RS becomes substantially uniform in the tire circumferential direction.

また、空気入りタイヤ１０によれば、気室部２２０の凹部分２２１の深さＤＰ１は、気室部２２０の端部２２０ｂにおいて、気室部２２０の端部２２０ａよりも深い。また、凹部分２２１の底面２２２は、曲線部分２２３を有する。つまり、気室部２２０にかみ込んだ小石などは、曲線部分２２３、凹部分２２１の両側面（陸部２１１）の概ね３点で支持されることになるため、底面２２２が平面な場合と比較して、気室部２２０から外れ易い。この結果、「石かみ」の発生を抑制できる。 Further, according to the pneumatic tire 10, the depth DP1 of the recessed portion 221 of the air chamber portion 220 is deeper at the end portion 220 b of the air chamber portion 220 than at the end portion 220 a of the air chamber portion 220. Further, the bottom surface 222 of the concave portion 221 has a curved portion 223. In other words, pebbles or the like that have bitten into the air chamber portion 220 are supported at approximately three points on the curved portion 223 and the side surfaces (land portion 211) of the concave portion 221, so that the bottom surface 222 is flat. Thus, it is easy to come off from the air chamber 220. As a result, the occurrence of “stone rock” can be suppressed.

また、狭窄溝部２３０と気室部２２０とによって、吸音したい周波数帯に対応したヘルムホルツ型共鳴器が構成されるため、周方向溝２１などによる気柱管共鳴音を効果的に低減できる。 In addition, since the Helmholtz resonator corresponding to the frequency band in which sound is desired to be absorbed is constituted by the narrowed groove portion 230 and the air chamber portion 220, air columnar resonance noise caused by the circumferential groove 21 and the like can be effectively reduced.

第１実施形態では、凹部分２２１の底面２２２は、曲線部分２２３及び接地面に連なる直線状部分２２４を有する。このため、かみ込んだ小石が空気入りタイヤ１０の転動に伴って移動させられると、曲線部分２２３に連なる直線状部分２２４を通じて小石などが気室部２２０から外れ易い。 In the first embodiment, the bottom surface 222 of the concave portion 221 has a curved portion 223 and a linear portion 224 that continues to the ground plane. For this reason, when the bited pebbles are moved along with the rolling of the pneumatic tire 10, the pebbles and the like easily come off the air chamber part 220 through the linear part 224 connected to the curved part 223.

狭窄溝部２３０は、気室部２２０の端部２２０ａに連通する。また、狭窄溝部２３０は、凹部分２２１の深さＤＰ１よりも深く、気室部２２０の端部２２０ｂまで延在する内溝部２３２を有する。さらに、内溝部２３２は、凹部分２２１と、陸部２１１（接地面）との間に形成される。このため、空気入りタイヤ１０が一定量摩耗した後においてもヘルムホルツ型共鳴器の機能を維持できる。 The narrowed groove portion 230 communicates with the end portion 220 a of the air chamber portion 220. Further, the narrowed groove portion 230 has an inner groove portion 232 that is deeper than the depth DP1 of the concave portion 221 and extends to the end portion 220b of the air chamber portion 220. Furthermore, the inner groove part 232 is formed between the recessed part 221 and the land part 211 (grounding surface). For this reason, the function of the Helmholtz resonator can be maintained even after the pneumatic tire 10 is worn out by a certain amount.

第１実施形態では、断面積Ｓは、曲線部分２２３の端部２２３ａから端部２２３ｂまで略同一である。また、リブ状陸部２４０に形成される接地面からの深さが最も深い位置（端部２２３ｂ）は、タイヤ周方向において、リブ状陸部２１０に形成される凹部分２２１の接地面からの深さが最も浅い位置（端部２２３ａ）と略同一である。このため、路面と接地する空気入りタイヤ１０のトレッド部分の剛性がタイヤ周方向において略均一となる。 In the first embodiment, the cross-sectional area S is substantially the same from the end 223a to the end 223b of the curved portion 223. Further, the position (end portion 223b) having the deepest depth from the ground contact surface formed in the rib-like land portion 240 is from the ground contact surface of the concave portion 221 formed in the rib-like land portion 210 in the tire circumferential direction. The depth is substantially the same as the shallowest position (end portion 223a). For this reason, the rigidity of the tread portion of the pneumatic tire 10 that contacts the road surface becomes substantially uniform in the tire circumferential direction.

［第２実施形態］
以下において、第２実施形態に係る空気入りタイヤ１０Ａについて、図面を参照しながら説明する。なお、上述した第１実施形態に係る空気入りタイヤ１０と同一部分には同一の符号を付して、相違する部分を主として説明する。 [Second Embodiment]
Hereinafter, a pneumatic tire 10A according to the second embodiment will be described with reference to the drawings. In addition, the same code | symbol is attached | subjected to the same part as the pneumatic tire 10 which concerns on 1st Embodiment mentioned above, and a different part is mainly demonstrated.

図９は、第２実施形態に係る空気入りタイヤ１０Ａの一部正面図である。なお、第２実施形態に係る空気入りタイヤ１０Ａの回転方向については、第２実施形態と同様に、図９の方向ＤＲである。 FIG. 9 is a partial front view of a pneumatic tire 10A according to the second embodiment. In addition, about the rotation direction of 10 A of pneumatic tires which concern on 2nd Embodiment, it is the direction DR of FIG. 9 similarly to 2nd Embodiment.

上述した第１実施形態では、気室部２２０の端部２２０ａは、気室部２２０の端部２２０ｂよりもタイヤ回転方向（方向ＤＲ）の前方に位置する。また、狭窄溝部１２１（細溝１２２）は、トレッド幅方向外側端がトレッド幅方向内側端よりもタイヤ回転方向の後方に位置する。 In 1st Embodiment mentioned above, the edge part 220a of the air chamber part 220 is located ahead of the tire rotation direction (direction DR) rather than the edge part 220b of the air chamber part 220. FIG. Further, the narrowed groove portion 121 (narrow groove 122) has a tread width direction outer end located behind the tread width direction inner end in the tire rotation direction.

また、傾斜細溝３１１のトレッド幅方向外側端は、トレッド幅方向内側端よりもタイヤ回転方向の後方に位置する。さらに、傾斜細溝３２１のトレッド幅方向外側端は、トレッド幅方向内側端よりもタイヤ回転方向の前方に位置している。このように、第１実施形態に係る空気入りタイヤ１０、右上がりパターンを有している（図１参照）。 Further, the outer end in the tread width direction of the inclined narrow groove 311 is located behind the inner end in the tread width direction in the tire rotation direction. Further, the outer end in the tread width direction of the inclined narrow groove 321 is located in front of the inner end in the tread width direction in the tire rotation direction. As described above, the pneumatic tire 10 according to the first embodiment has a right-up pattern (see FIG. 1).

これに対して、第２実施形態では、図９に示すように、気室部２２０の端部２２０ａは、気室部２２０の端部２２０ｂよりもタイヤ回転方向（方向ＤＲ）の後方に位置する。つまり、外溝部２３１は、気室部２２０のタイヤ回転方向の後方に位置する端部２２０ａまで延びる。 On the other hand, in 2nd Embodiment, as shown in FIG. 9, the edge part 220a of the air chamber part 220 is located in the back of a tire rotation direction (direction DR) rather than the edge part 220b of the air chamber part 220. . That is, the outer groove portion 231 extends to the end portion 220a located at the rear of the air chamber portion 220 in the tire rotation direction.

また、狭窄溝部１２１は、トレッド幅方向外側端がトレッド幅方向内側端よりもタイヤ回転方向の前方に位置する。また、傾斜細溝３１１のトレッド幅方向外側端は、トレッド幅方向内側端よりもタイヤ回転方向の前方に位置する。さらに、傾斜細溝３２１のトレッド幅方向外側端は、トレッド幅方向内側端よりもタイヤ回転方向の後方に位置している。 Further, the narrowed groove 121 is located at the front end in the tire rotation direction at the outer end in the tread width direction than at the inner end in the tread width direction. Further, the outer end in the tread width direction of the inclined narrow groove 311 is positioned in front of the inner end in the tread width direction in the tire rotation direction. Furthermore, the outer end in the tread width direction of the inclined narrow groove 321 is located behind the inner end in the tread width direction in the tire rotation direction.

このように、第２実施形態に係る空気入りタイヤ１０Ａは、左上がりパターンを有している。この場合、空気入りタイヤ１０Ａのバランスを考慮して、不図示のベルト層を構成するコードは、トレッド面視においてトレッドパターンとは逆側に傾斜している（すなわち、右上がりコードである）ことが好ましい。 Thus, the pneumatic tire 10A according to the second embodiment has a left-up pattern. In this case, in consideration of the balance of the pneumatic tire 10A, the cord constituting the belt layer (not shown) is inclined to the opposite side to the tread pattern in the tread surface view (that is, the cord is a right-up cord). Is preferred.

［変更例］
以下において、本発明の変更例に係る気室部について、図面を参照しながら説明する。具体的には、（１）変更例１、（２）変更例２、（３）変更例３、（４）変更例４、（５）変更例５、（６）変更例６について説明する。なお、上述した第１実施形態に係る空気入りタイヤ１０や第２実施形態に係る空気入りタイヤ１０Ａと同一部分には同一の符号を付して、相違する部分を主として説明する。 [Example of change]
Hereinafter, an air chamber according to a modified example of the present invention will be described with reference to the drawings. Specifically, (1) Modification Example 1, (2) Modification Example 2, (3) Modification Example 3, (4) Modification Example 4, (5) Modification Example 5, and (6) Modification Example 6 will be described. In addition, the same code | symbol is attached | subjected to the same part as the pneumatic tire 10 which concerns on 1st Embodiment mentioned above, or the pneumatic tire 10A which concerns on 2nd Embodiment, and a different part is mainly demonstrated.

（１）変更例１
図１０は、上述した第１実施形態の図２に対応する。具体的には、図１０は、本発明の変更例１に係る気室部を示す。 (1) Modification 1
FIG. 10 corresponds to FIG. 2 of the first embodiment described above. Specifically, FIG. 10 shows an air chamber according to a first modification of the present invention.

図１０に示すように、気室部１３０Ｃ，１３０Ｄの底面は、タイヤ周方向に沿った断面視において正弦波の形状である。上述した気室部１３０Ａ及び気室部１３０Ｂと同様に、気室部１３０Ｃの底面の最高位置１３２ａと、気室部１３０Ｂの底面の最高位置１３２ａとは、タイヤ周方向において、間隔Ｐの略半分ずれている。 As shown in FIG. 10, the bottom surfaces of the air chamber portions 130 C and 130 D have a sinusoidal shape in a sectional view along the tire circumferential direction. Similarly to the air chamber portion 130A and the air chamber portion 130B described above, the highest position 132a on the bottom surface of the air chamber portion 130C and the highest position 132a on the bottom surface of the air chamber portion 130B are approximately half of the interval P in the tire circumferential direction. It's off.

このように底面の形状が正弦波の場合、路面と接地する空気入りタイヤ１０のトレッド部分の溝ボリューム（ネガティブ率）が、タイヤ周方向においてより均一になる。 As described above, when the shape of the bottom surface is a sine wave, the groove volume (negative rate) of the tread portion of the pneumatic tire 10 that contacts the road surface becomes more uniform in the tire circumferential direction.

（２）変更例２
図１１は、本発明の変更例２に係る気室部を示す。図１１に示すように、気室部１３０Ｅ，１３０Ｆの底面は、タイヤ周方向に沿った断面視において山形（三角形）である。なお、最高位置１３２ａの配置関係は、上述した第１実施形態と同様である。 (2) Modification example 2
FIG. 11 shows an air chamber according to a second modification of the present invention. As shown in FIG. 11, the bottom surfaces of the air chamber portions 130 E and 130 F have a mountain shape (triangle) in a cross-sectional view along the tire circumferential direction. The arrangement relationship of the highest position 132a is the same as that in the first embodiment described above.

（３）変更例３
図１２は、本発明の変更例３に係る気室部を示す。図１２に示すように、気室部１３０Ｇ，１３０Ｈの底面は、タイヤ周方向に沿った断面視において円弧を形成するアーチ状である点において上述した気室部１３０Ａ及び気室部１３０Ｂと同様である。 (3) Modification 3
FIG. 12 shows an air chamber according to a third modification of the present invention. As shown in FIG. 12, the bottom surfaces of the air chamber portions 130G and 130H are similar to the air chamber portion 130A and the air chamber portion 130B described above in that they have an arch shape that forms an arc in a cross-sectional view along the tire circumferential direction. is there.

但し、気室部１３０Ｇ，１３０Ｈでは、気室部の底面を形成する円弧の中心は、底面よりもタイヤ径方向内側ではなく、タイヤ径方向外側に位置する。つまり、気室部１３０Ｇ，１３０Ｈの底面は、気室部１３０Ａ及び気室部１３０Ｂと比較すると逆アーチ状である。なお、最高位置１３２ａの配置関係は、上述した第１実施形態と同様である。 However, in the air chamber portions 130G and 130H, the center of the arc forming the bottom surface of the air chamber portion is located not on the tire radial direction inner side but on the tire radial direction outer side than the bottom surface. That is, the bottom surfaces of the air chamber portions 130G and 130H have a reverse arch shape as compared with the air chamber portion 130A and the air chamber portion 130B. The arrangement relationship of the highest position 132a is the same as that in the first embodiment described above.

（４）変更例４
図１３（ａ）は、本発明の変更例４に係るリブ状陸部１１０Ａの一部を示す。図１３（ｂ）は、本発明の変更例４に係るリブ状陸部１１０Ａの断面（図１３（ａ）のＦ１３−Ｆ１３断面）を示す。 (4) Modification 4
Fig.13 (a) shows a part of 110 A of rib-shaped land parts which concern on the modification 4 of this invention. FIG.13 (b) shows the cross section (F13-F13 cross section of Fig.13 (a)) of the rib-shaped land part 110A which concerns on the modification 4 of this invention.

図１３（ａ）及び（ｂ）に示すように、リブ状陸部１１０Ａのタイヤ周方向（方向Ｄ１）に沿った縁部分には、面取り部１５０が形成される。具体的には、面取り部１５０は、トレッド幅方向及びタイヤ径方向に沿った断面（図１３（ｂ）参照）において、曲線（Ｒ状）によって構成される。 As shown in FIGS. 13A and 13B, a chamfered portion 150 is formed at the edge portion along the tire circumferential direction (direction D1) of the rib-like land portion 110A. Specifically, the chamfered portion 150 is configured by a curved line (R shape) in a cross section (see FIG. 13B) along the tread width direction and the tire radial direction.

なお、面取り部１５０は、トレッド幅方向及びタイヤ径方向に沿った断面において、必ずしも曲線によって構成される必要はなく、傾斜面（いわゆる、テーパ状）であってもよい。 The chamfered portion 150 does not necessarily need to be configured by a curve in the cross section along the tread width direction and the tire radial direction, and may be an inclined surface (so-called tapered shape).

また、面取り部１５０は、必ずしもリブ状陸部１１０Ａのタイヤ周方向（方向Ｄ１）に沿った縁部分全体に形成される必要はなく、リブ状陸部１１０Ａのタイヤ周方向に沿った縁部分のうち、少なくとも狭窄溝部１２１と連通した部分に形成されていることが好ましい。 Further, the chamfered portion 150 is not necessarily formed on the entire edge portion along the tire circumferential direction (direction D1) of the rib-like land portion 110A, and the edge portion of the rib-like land portion 110A along the tire circumferential direction is not necessarily formed. Of these, at least a portion communicating with the narrowed groove 121 is preferably formed.

また、面取り部１５０は、必ずしもリブ状陸部１１０Ａのみに形成される必要はなく、リブ状陸部１１０Ａを構成する陸部１２０Ａ、陸部１２０Ｂ及び陸部１４０のぞれぞれのタイヤ周方向に沿った縁部分に形成されていてもよい。また、面取り部１５０は、リブ状陸部２１０，２４０（図１参照）のぞれぞれのタイヤ周方向に沿った縁部分に形成されていてもよい。 Further, the chamfered portion 150 is not necessarily formed only in the rib-like land portion 110A, and the tire circumferential direction of each of the land portion 120A, the land portion 120B, and the land portion 140 constituting the rib-like land portion 110A. It may be formed in the edge part along. Moreover, the chamfered part 150 may be formed in the edge part along the tire circumferential direction of each of the rib-shaped land parts 210 and 240 (refer FIG. 1).

このような面取り部１５０が形成される（特に、面取り部１５０が曲線（Ｒ状）に構成される）ことによって、摩耗時の狭窄溝部１２１の体積（大きさ）の減少を抑制でき、ヘルムホルツ型共鳴器の機能をより長く持続できる。このため、石かみの抑制とヘルムホルツ型共鳴器の機能とを両立できる。 By forming such a chamfered portion 150 (particularly, the chamfered portion 150 is configured in a curved shape (R shape)), it is possible to suppress a decrease in the volume (size) of the narrowed groove 121 at the time of wear, and a Helmholtz type The function of the resonator can be maintained longer. For this reason, it is possible to achieve both the suppression of stone biting and the function of a Helmholtz resonator.

（５）変更例５
図１４は、トレッド平面視における気室部１３０Ａ及び気室部１３０Ｂ近傍を示す。図１４に示すように、気室部１３０Ａ及び気室部１３０Ｂにおける底面１３２の最高位置１３２ａは、トレッド面視において、細溝１２２と略同一方向となるように、トレッド幅方向に傾斜する。すなわち、最高位置１３２ａのトレッド幅方向における外側端１３２ｅ１と、最高位置１３２ａのトレッド幅方向における内側端１３２ｅ２とは、トレッド幅方向に対してずれている。 (5) Modification 5
FIG. 14 shows the vicinity of the air chamber portion 130A and the air chamber portion 130B in a tread plan view. As shown in FIG. 14, the highest position 132a of the bottom surface 132 in the air chamber portion 130A and the air chamber portion 130B is inclined in the tread width direction so as to be substantially in the same direction as the narrow groove 122 in the tread surface view. That is, the outer end 132e1 in the tread width direction of the highest position 132a and the inner end 132e2 in the tread width direction of the highest position 132a are shifted from the tread width direction.

同様に、底面１３２の最低位置１３２ｂは、トレッド面視において、狭窄溝部１２１と略同一方向となるように、トレッド幅方向に傾斜する。すなわち、最低位置１３２ｂのトレッド幅方向における外側端１３２ｅ３と、最低位置１３２ｂのトレッド幅方向における内側端１３２ｅ４とは、トレッド幅方向に対してずれている。 Similarly, the lowest position 132b of the bottom surface 132 is inclined in the tread width direction so as to be substantially in the same direction as the narrowed groove 121 in the tread surface view. That is, the outer end 132e3 in the tread width direction of the lowest position 132b and the inner end 132e4 in the tread width direction of the lowest position 132b are shifted from the tread width direction.

このような最高位置１３２ａや最低位置１３２ｂである場合、空気入りタイヤ１０の新品時や一定量摩耗した後においても、気室部１３０Ａ及び気室部１３０Ｂ（例えば、最高位置１３２ａ）が集中して路面ＲＳに接することを防止できる。このため、空気入りタイヤ１０と路面ＲＳとの衝撃によるパターンノイズを効果的に低減できる。 In the case of the highest position 132a and the lowest position 132b, the air chamber portion 130A and the air chamber portion 130B (for example, the highest position 132a) are concentrated even when the pneumatic tire 10 is new or after a certain amount of wear. It can prevent contacting with road surface RS. For this reason, the pattern noise by the impact with the pneumatic tire 10 and road surface RS can be reduced effectively.

（６）変更例６
図１５（ａ）は、本発明の変更例５に係るリブ状陸部１１０Ｂの一部斜視図である。図１５（ｂ）は、本発明の変更例５に係るリブ状陸部１１０Ｂの断面（図１５（ａ）のＦ１５−Ｆ１５断面）を示す。 (6) Modification 6
FIG. 15 (a) is a partial perspective view of a rib-like land portion 110B according to Modification 5 of the present invention. FIG.15 (b) shows the cross section (F15-F15 cross section of Fig.15 (a)) of the rib-shaped land part 110B which concerns on the modification 5 of this invention.

図１５（ａ）及び（ｂ）に示すように、リブ状陸部１１０Ｂを構成する陸部１２０Ａ，１４０と気室部１３０Ａとの間には、周方向サイプ３０が形成される。周方向サイプ３０は、タイヤ周方向（方向Ｄ１）に沿って延びるとともに、タイヤ周方向における両端が凹部分１３１に連通する。同様に、リブ状陸部１１０Ａを構成する陸部１２０Ｂ，１４０と気室部１３０Ｂとの間にも、周方向サイプ３０が形成される。 As shown in FIGS. 15A and 15B, a circumferential sipe 30 is formed between the land portions 120A and 140 constituting the rib-like land portion 110B and the air chamber portion 130A. The circumferential sipe 30 extends along the tire circumferential direction (direction D1), and both ends in the tire circumferential direction communicate with the recess 131. Similarly, the circumferential sipe 30 is also formed between the land portions 120B and 140 constituting the rib-shaped land portion 110A and the air chamber portion 130B.

なお、周方向サイプ３０の両端は、必ずしも凹部分１３１に連通する必要はなく、少なくとも何れか一端が凹部分１３１に連通していればよい。 It should be noted that both ends of the circumferential sipe 30 do not necessarily need to communicate with the recessed portion 131, and it is sufficient that at least one end thereof communicates with the recessed portion 131.

このような周方向サイプ３０が形成される場合、周方向サイプ３０が形成されていない場合と比較して、空気入りタイヤ１０が一定量摩耗した後において、陸部１２０Ａ，１２０Ｂ，１４０や気室部１３０Ａ，１３０Ｂの圧縮剛性が低くなる。このため、路面ＲＳの凹凸による振動が空気入りタイヤ１０に伝わり難くなり、パターンノイズを効果的に低減できる。 When such a circumferential sipe 30 is formed, the land portions 120A, 120B, 140 and the air chambers after the pneumatic tire 10 is worn out by a certain amount as compared with the case where the circumferential sipe 30 is not formed. The compression rigidity of the portions 130A and 130B is reduced. For this reason, the vibration due to the unevenness of the road surface RS is not easily transmitted to the pneumatic tire 10, and the pattern noise can be effectively reduced.

［その他の実施形態］
上述したように、本発明の実施形態を通じて本発明の内容を開示したが、この開示の一部をなす論述及び図面は、本発明を限定するものであると理解すべきではない。この開示から当業者には様々な代替実施の形態、実施例が明らかとなる。例えば、本発明の実施形態は、次のように変更することができる。 [Other Embodiments]
Although the contents of the present invention have been disclosed through the embodiments of the present invention as described above, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments and examples will be apparent to those skilled in the art. For example, the embodiment of the present invention can be modified as follows.

上述した変更例以外にも、気室部の底面形状は、ジグザク状、階段状、直線と円弧の組合せなどであってもよい。 In addition to the modification example described above, the bottom surface shape of the air chamber portion may be a zigzag shape, a staircase shape, a combination of a straight line and an arc, or the like.

上述した第１実施形態や第２実施形態では、気室部１３０Ａと気室部１３０Ｂとのタイヤ周方向における位置、及び気室部２２０と気室部２５０とのタイヤ周方向における位置関係は、空気入りタイヤ１０のトレッド部分の剛性をタイヤ周方向において均一にするため、一致していなかったが、必ずしもこのような位置関係にしなくてもよい。 In the first embodiment and the second embodiment described above, the position of the air chamber portion 130A and the air chamber portion 130B in the tire circumferential direction and the positional relationship of the air chamber portion 220 and the air chamber portion 250 in the tire circumferential direction are: In order to make the rigidity of the tread portion of the pneumatic tire 10 uniform in the tire circumferential direction, they do not coincide with each other, but such a positional relationship is not necessarily required.

上述した第１実施形態や第２実施形態では、狭窄溝部２３０は、気室部２２０の端部２２０ａに連通するとともに、端部２２０ｂまで延在する内溝部２３２を有していたが、狭窄溝部２３０は、必ずしもこのような形状でなくても構わない。例えば、狭窄溝部２３０は、気室部２２０の中央部分に連通するようにしてもよい。同様に、狭窄溝部１２１の端部１２１ａは、必ずしも底面１３２の最低位置１３２ｂにおいて凹部分１３１に連通しなくても構わない。 In the first embodiment and the second embodiment described above, the narrowed groove 230 has the inner groove 232 that communicates with the end 220a of the air chamber 220 and extends to the end 220b. 230 does not necessarily have such a shape. For example, the narrowed groove 230 may communicate with the central portion of the air chamber 220. Similarly, the end 121a of the narrowed groove 121 may not necessarily communicate with the concave portion 131 at the lowest position 132b of the bottom surface 132.

上述した第１実施形態や第２実施形態では、陸部１２０Ａに細溝１２２が形成されていたが、細溝１２２は、形成されなくてもよい。また、上述した実施形態では、気室部１３０Ａと気室部１３０Ｂとは、同一のリブ状陸部に設けられていたが、両気室部は、別個のリブ状陸部にそれぞれ設けてもよい。 In the first embodiment and the second embodiment described above, the narrow groove 122 is formed in the land portion 120A. However, the narrow groove 122 may not be formed. In the above-described embodiment, the air chamber portion 130A and the air chamber portion 130B are provided in the same rib-shaped land portion. However, both air chamber portions may be provided in separate rib-shaped land portions. Good.

上述した第１実施形態や第２実施形態では、周方向溝１１，１２，２１，２２は、タイヤ周方向に沿って直線状に延びていたが、周方向溝は、タイヤ周方向に沿って延びていれば、必ずしも直線状に限らず、ジグザグ状や波形状でもよい。 In the first and second embodiments described above, the circumferential grooves 11, 12, 21, and 22 extend linearly along the tire circumferential direction, but the circumferential grooves extend along the tire circumferential direction. As long as it extends, it is not necessarily a straight line shape, and may be a zigzag shape or a wave shape.

このように、本発明は、ここでは記載していない様々な実施の形態などを含むことは勿論である。したがって、本発明の技術的範囲は、上述の説明から妥当な特許請求の範囲に係る発明特定事項によってのみ定められるものである。 As described above, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention is defined only by the invention specifying matters according to the scope of claims reasonable from the above description.

１０…空気入りタイヤ、１１，１２，２１，２２…周方向溝、１１０…リブ状陸部、１２０Ａ，１２０Ｂ…陸部、１２１…狭窄溝部、１２１ａ，１２１ｂ…端部、１２２…細溝、１３０Ａ〜１３０Ｈ…気室部、１３１…凹部分、１３２…底面、１３２ａ…最高位置、１３２ｂ…最低位置、１４０…陸部、２１０…リブ状陸部、２１１…陸部、２２０…気室部、２４０…リブ状陸部、２２０ａ，２２０ｂ…端部、２２１…凹部分、２２２…底面、２２３…曲線部分、２２４…直線状部分、２２３ａ，２２３ｂ，２２４ａ，２２４ｂ…端部、２３０…狭窄溝部、２３１…外溝部、２３２…内溝部、２４１…陸部、２５０…気室部、ＣＴ１，ＣＴ２…中心、ＤＰ１，ＤＰ２…深さ、Ｈ…高さ、Ｐ…間隔、Ｒ１，Ｒ２…ヘルムホルツ型共鳴器、ＲＳ…路面、Ｓ…断面積、Ｗ…幅 DESCRIPTION OF SYMBOLS 10 ... Pneumatic tire, 11, 12, 21, 22 ... Circumferential groove | channel, 110 ... Rib-like land part, 120A, 120B ... Land part, 121 ... Narrow groove part, 121a, 121b ... End part, 122 ... Narrow groove, 130A ˜130H: Air chamber portion, 131: Recessed portion, 132: Bottom surface, 132a: Highest position, 132b: Lowest position, 140: Land portion, 210: Rib land portion, 211: Land portion, 220: Air chamber portion, 240 ... rib-like land portion, 220a, 220b ... end portion, 221 ... concave portion, 222 ... bottom surface, 223 ... curved portion, 224 ... linear portion, 223a, 223b, 224a, 224b ... end portion, 230 ... narrowed groove portion, 231 ... outer groove part, 232 ... inner groove part, 241 ... land part, 250 ... air chamber part, CT1, CT2 ... center, DP1, DP2 ... depth, H ... height, P ... interval, R1, R2 ... Helmholtz resonator RS ... Surface, S ... cross-sectional area, W ... width

Claims

A tire comprising a rib-like land portion adjacent to a circumferential groove extending along the tire circumferential direction and extending along the tire circumferential direction,
An air chamber portion in which a concave portion recessed toward the inner side in the tire radial direction repeats at a predetermined interval along the tire circumferential direction;
A narrowed groove portion communicating with the concave portion is formed in the rib-like land portion,
The height from the bottom surface of the air chamber portion to the contact surface where the rib-shaped land portion contacts the road surface changes along the tire circumferential direction,
The volume of the space formed by the narrowed groove and the road surface is smaller than the volume of the space formed by the concave portion and the road surface,
One end of the narrowed groove portion communicates with a closed space formed by the air chamber portion and the road surface, and the other end of the narrowed groove portion communicates with the circumferential groove.
The bottom surface of the air chamber part is in contact with the road surface at the highest position where the height to the ground contact surface is the highest,
The air chamber portion is formed by the bottom surface between the two highest positions adjacent to each other and the road surface in contact with the land portion,
The air chamber is
A first air chamber,
A second air chamber provided at a position different from the first air chamber in the tread width direction,
The shape of the bottom surface of the second air chamber portion is substantially the same as the shape of the bottom surface of the first air chamber portion,
The first air chamber portion and the second air chamber portion are such that the concave portion repeats at the predetermined interval,
The tire in which the highest position on the bottom surface of the first air chamber portion and the highest position on the bottom surface of the second air chamber portion are shifted by a half phase at the predetermined interval in the tire circumferential direction.

The tire according to claim 1, wherein the first air chamber portion and the second air chamber portion are provided in the same rib-shaped land portion.

Of the edge portion along the tire circumferential direction of the rib-like land portion, a chamfered portion is formed at least in a portion communicating with the narrowed groove portion,
The tire according to claim 1 or 2, wherein the chamfered portion is configured by a curve in a cross section along the tread width direction and the tire radial direction.

2. The tire according to claim 1, wherein a bottom surface of the air chamber portion is in line contact with the road surface along a direction different from a tire circumferential direction.

The tire according to any one of claims 1 to 4, wherein one end of the narrowed groove portion communicates with the concave portion at a lowest position where the bottom surface is lowest.

The tire according to any one of claims 1 to 5, wherein the bottom surface of the air chamber portion repeats an arch shape forming an arc in a cross-sectional view along the tire circumferential direction.

The tire according to claim 6, wherein the center of the arc is located on the inner side in the tire radial direction than the bottom surface.

The tire according to any one of claims 1 to 5, wherein a bottom surface of the air chamber portion has a sinusoidal shape in a cross-sectional view along the tire circumferential direction.

The tire according to any one of claims 1 to 8, wherein the highest position where the position of the bottom surface of the air chamber portion is highest is inclined in the tread width direction in a tread surface view.

The tire according to any one of claims 1 to 9, wherein the lowest position where the position of the bottom surface of the air chamber portion is the lowest is inclined in the tread width direction when viewed from the tread surface.

The circumferential sipe that extends along the tire circumferential direction and at least one end communicates with the concave portion is formed between the rib-shaped land portion and the air chamber portion. The tire according to item.