JP2011152836A

JP2011152836A - Pneumatic tire for construction vehicle

Info

Publication number: JP2011152836A
Application number: JP2010014681A
Authority: JP
Inventors: Hidetoshi Yoda; 秀敏依田
Original assignee: Bridgestone Corp
Current assignee: Bridgestone Corp
Priority date: 2010-01-26
Filing date: 2010-01-26
Publication date: 2011-08-11

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pneumatic tire for a construction vehicle having high abrasion resistance, and capable of restraining the deterioration in heating performance, even when used for any of a driving wheel and a steered wheel. <P>SOLUTION: Both lug grooves 31 positioned in both side areas 30 are arranged so that the extending direction of turning to the respective tread ends from the tire equator E side, inclines at predetermined angles γ<SB>1</SB>and γ<SB>2</SB>from the tire circumferential direction, and are characterized in that its inclinations γ<SB>1</SB>and γ<SB>2</SB>fall within a range of 100-135° by measuring on the obtuse angle side to the tire circumferential direction C. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

本発明は、空気入りタイヤ、特に、主に建設現場や鉱山等で用いられるダンプトラック等に用いられる建設車両用空気入りタイヤに関する。 The present invention relates to a pneumatic tire, and more particularly to a pneumatic tire for a construction vehicle used for a dump truck or the like mainly used at a construction site or a mine.

従来の建設車両用空気入りタイヤとしては、トレッドのタイヤ幅方向両側に位置する複数のラグ溝が配設された空気入りタイヤが一般的である。この建設車両用空気入りタイヤでは、タイヤの摩耗ライフ向上のため、トレッドゲージを大きくしたり、溝部面積を小さくすることによって、トレッドボリュームを大きくするのが一般的である。 As a conventional pneumatic tire for construction vehicles, a pneumatic tire in which a plurality of lug grooves located on both sides of the tread in the tire width direction is generally used. In this pneumatic tire for construction vehicles, in order to improve the wear life of the tire, it is common to increase the tread volume by increasing the tread gauge or decreasing the groove area.

しかし、上記手段を用いて耐摩耗性を向上させた場合には、とりわけタイヤの負荷転動
時におけるトレッド部の発熱性の悪化、すなわちトレッド部の温度上昇を招く傾向がある
。このようなトレッド部の温度上昇は、トレッド部のヒートセパレーション等の故障を招くため、好ましくない。 However, when the wear resistance is improved by using the above-described means, there is a tendency that the heat generation of the tread portion is deteriorated, that is, the temperature of the tread portion is increased, particularly during tire rolling. Such a temperature rise in the tread portion is not preferable because it causes a failure such as heat separation in the tread portion.

この対策として、例えば特許文献１には、所定の幅方向細溝を有するトレッドを用いることで、トレッド溝内に流れる風を前記幅方向溝内に効率的に送り込み、タイヤセンター部を空冷することで、発熱性の悪化を抑制する建設車両用タイヤが挙げられている。また、特許文献２では、トレッドのショルダー領域を形成する各ブロック陸部に、所定の横副溝を形成することで、踏み込み端が路面から蹴り出される際に、該踏み込み端が速やかに路面から離れるようになり、陸部剛性を大きく低下させることなく踏み込み端の偏摩耗を低減させる空気入りタイヤが開示されている。 As a countermeasure, for example, in Patent Document 1, by using a tread having a predetermined narrow groove in the width direction, the wind flowing in the tread groove is efficiently sent into the groove in the width direction, and the tire center portion is air-cooled. Thus, construction vehicle tires that suppress exothermic deterioration are cited. Further, in Patent Document 2, by forming a predetermined lateral sub-groove in each block land portion that forms the shoulder region of the tread, when the stepping end is kicked off from the road surface, the stepping end is quickly removed from the road surface. There has been disclosed a pneumatic tire that comes apart and reduces uneven wear at the tread edge without significantly reducing land rigidity.

しかしながら、近年、建設車両の大型化に伴うタイヤサイズの大型化、偏平化及び重荷重化が進んだことにより、前記トレッド部の発熱性の悪化はさらに顕著になる傾向にあるため、高い耐摩耗性を有し、さらに、発熱性の悪化を抑制できる建設車両用空気入りタイヤの開発が、依然重要視されている。また、駆動輪として用いられるタイヤについては、トラクションを要因とした摩耗について、さらなる改善を図る必要があった。
さらに、鉱山等で使用される建設車両では、パンクによるリスク低減や、前輪／後輪での磨耗の均一化を図り、タイヤの磨耗ライフの向上などを目的として、新品のタイヤを、まず前輪に装着して一定期間使用した後、後輪に装着することが通常であることから、駆動輪として用いられる場合だけでなく、操舵輪として用いられた場合の旋回時のサイドフォース入力等に起因した摩耗についても改善する必要があった。 However, in recent years, the increase in tire size, flattening, and heavy load due to the increase in the size of construction vehicles has led to the deterioration of the heat generation of the tread portion becoming more prominent. The development of pneumatic tires for construction vehicles that are capable of suppressing the deterioration of heat generation is still regarded as important. Further, for tires used as drive wheels, it was necessary to further improve the wear caused by traction.
Furthermore, in construction vehicles used in mines, etc., new tires are first applied to the front wheels in order to reduce risks due to punctures, to equalize wear on the front and rear wheels, and to improve the wear life of the tires. Since it is usually mounted on the rear wheel after mounting and used for a certain period of time, it was caused not only when used as a drive wheel, but also due to side force input during turning when used as a steering wheel It was also necessary to improve the wear.

特開２００７−１９１０９３号公報JP 2007-191093 A 特開２００７−８３８２２号公報JP 2007-83822 A

本発明の目的は、トレッドの適正化を図ることで、駆動輪及び操舵輪のいずれに用いられる場合であっても、高い耐摩耗性を有し、さらに、発熱性の悪化を抑制できる建設車両用空気入りタイヤを提供することにある。 An object of the present invention is to provide a construction vehicle that has high wear resistance and can suppress deterioration in heat generation, regardless of whether the tread is optimized for use as a drive wheel or a steering wheel. It is to provide a pneumatic tire for use.

本発明者は、トレッドを中央域と該中央域のタイヤ幅方向両側に位置する両側方域に区分したときの該側方域に、複数本のラグ溝を有する建設車両用空気入りタイヤにおいて、上記の課題を解決すべく検討を重ねた。
そして、中央域に、タイヤ周方向に対し所定の角度で延在する第１傾斜溝部と、該第１傾斜溝部とはタイヤ周方向に対し逆向きの角度で延在する第２傾斜溝部とを交互に連結して、タイヤ周方向に沿ってジグザグ状に連続して延びる１本のジグザグ細溝を設け、各側方域に、前記ラグ溝のタイヤ幅方向内側部を通り、タイヤ周方向に延びる１本の側方細溝を設け、前記ラグ溝のタイヤ幅方向内側部が、第１傾斜溝部と第２傾斜溝部の連結部のうちの近い方の連結部付近とタイヤ幅方向に向かい合う配置関係にあり、かつ前記ラグ溝のタイヤ幅方向内側部と、前記近い方の連結部との間に、１本の幅方向細溝を設け、トレッド部に、ジグザグ細溝、側方細溝及び幅方向細溝を配設することにより、複数個の５角形以上の多角形のブロック陸部がタイヤ周方向に沿って並置された２列のブロック列を形成することで、複数個の５角形以上の多角形のブロック陸部がタイヤ周方向に沿って並置された２列のブロック列を形成することで、ダンプトラック等の駆動輪として用いられる場合において、走行時、先に踏み込んだ多角形ブロック陸部が前記ジグザグ細溝を挟んで対向する多角形ブロックを引き込み、引き込まれた多角形ブロックが踏み込む前から変形した状態にあるため、踏み込んだ瞬間から路面と該引き込まれた多角形ブロックとの間に剪断力が発生し、駆動性能が向上する結果、タイヤの蹴り出し時の剪断力が低減し、駆動輪として用いた場合の耐摩耗性が向上することを見出した。 In the pneumatic tire for a construction vehicle having a plurality of lug grooves in the lateral region when the tread is divided into a central region and both lateral regions located on both sides in the tire width direction of the central region, The study was repeated to solve the above problems.
And in the central region, a first inclined groove portion extending at a predetermined angle with respect to the tire circumferential direction, and a second inclined groove portion extending at an angle opposite to the tire circumferential direction with respect to the first inclined groove portion. One zigzag narrow groove that is alternately connected and continuously extends in a zigzag shape along the tire circumferential direction is provided, and in each side region, the inner side in the tire width direction of the lug groove is passed in the tire circumferential direction. An extending side narrow groove is provided, and the inner side portion in the tire width direction of the lug groove faces the vicinity of the connecting portion of the connecting portion of the first inclined groove portion and the second inclined groove portion in the tire width direction. A width direction narrow groove is provided between the inner side portion of the lug groove in the tire width direction and the closer connecting portion, and the tread portion has a zigzag narrow groove, a lateral narrow groove, and By arranging the narrow grooves in the width direction, a plurality of pentagonal polygonal block land portions are formed. By forming two block rows juxtaposed along the circumferential direction of the ear, a plurality of polygonal block land portions of five or more pentagons are formed side by side along the tire circumferential direction. Thus, when used as a driving wheel for a dump truck or the like, when running, the polygon block land portion that has been stepped in first pulls in the polygon block facing the zigzag narrow groove, and the polygon block is drawn in. Since it is in a deformed state before it is stepped on, shearing force is generated between the road surface and the drawn polygonal block from the moment of stepping on, and the driving performance is improved. It has been found that the wear resistance is improved when used as a drive wheel.

さらに、本発明者は、操舵輪（前輪）の摩耗は、操舵時にサイドフォースによる入力を受け、踏み込み時にセンター側に変形した踏面が、蹴り出し時にショルダー側（タイヤ幅方向外側）に戻る動きの際にすべりを生じることが原因であることに着目した。そして、さらに鋭意研究を重ねた結果、トレッド部に、ラグ溝及び周方向細溝を配設することにより複数個の４角形以上の側方ブロック陸部がタイヤ周方向に沿って並置された２列の側方ブロック列を形成し、前記両側方域に位置するラグ溝を、ともに、タイヤ赤道側からそれぞれのトレッド端に向かう延在方向がタイヤ周方向から所定の角度（タイヤ周方向に対して鈍角側で測定して100〜135°の範囲）で傾斜するように配置し、ラグ溝がセンター側から接地していくように本発明のタイヤを建設車両に装着することで、踏み込み時に各側方ブロック陸部３３ａ、３３ｂがショルダー側に変形し、蹴り出し時に元の形状に戻る（センター側に戻る）ため、摩耗の原因となる蹴り出し時のショルダー側の動きを打ち消すことができ、操舵輪として用いた場合の耐摩耗性の向上を図れることを見出した。 Further, the inventor of the present invention is that the wear of the steered wheel (front wheel) receives input from the side force during steering, and the tread surface deformed to the center side when stepped on returns to the shoulder side (outside in the tire width direction) when kicking out. We paid attention to the cause of slippage. As a result of further earnest research, a plurality of quadrangular side block land portions are juxtaposed along the tire circumferential direction by arranging lug grooves and circumferential narrow grooves in the tread portion. A side block row of rows is formed, and the lug grooves located in the both side regions are extended at a predetermined angle from the tire circumferential direction (with respect to the tire circumferential direction). In the range of 100 to 135 ° measured on the obtuse angle side, and by mounting the tire of the present invention on the construction vehicle so that the lug groove contacts the center side, Since the side block land portions 33a and 33b are deformed to the shoulder side and return to the original shape when kicked back (return to the center side), the movement on the shoulder side when kicking that causes wear can be canceled, As a steering wheel It found that thereby improving the wear resistance when used.

本発明は、このような知見に基づきなされたもので、その要旨は以下の通りである。
（１）トレッドを中央域と該中央域のタイヤ幅方向両側に位置する両側方域に区分したときの該側方域に、複数本のラグ溝を有する建設車両用空気入りタイヤにおいて、中央域に、タイヤ周方向に対し所定の角度で延在する第１傾斜溝部と、該第１傾斜溝部とはタイヤ周方向に対し逆向きの角度で延在する第２傾斜溝部とを交互に連結して、タイヤ周方向に沿ってジグザグ状に連続して延びる１本のジグザグ細溝を設け、各側方域に、前記ラグ溝のタイヤ幅方向内側部を通り、タイヤ周方向に延びる１本の側方細溝を設け、前記ラグ溝のタイヤ幅方向内側部が、第１傾斜溝部と第２傾斜溝部の連結部のうちの近い方の連結部付近とタイヤ幅方向に向かい合う配置関係にあり、かつ前記ラグ溝のタイヤ幅方向内側部と、前記近い方の連結部との間に、１本の幅方向細溝を設け、トレッド部に、ジグザグ細溝、側方細溝及び幅方向細溝を配設することにより、複数個の５角形以上の多角形のブロック陸部がタイヤ周方向に沿って並置された２列の多角形ブロック列を形成し、ラグ溝及び周方向細溝を配設することにより、複数個の４角形以上の側方ブロック陸部がタイヤ周方向に沿って並置された２列の側方ブロック列を形成してなり、前記両側方域に位置するラグ溝は、ともに、タイヤ赤道側からそれぞれのトレッド端に向かう延在方向がタイヤ周方向から所定の角度で傾斜するように配置し、その傾斜角度がタイヤ周方向に対して鈍角側で測定して100〜135°の範囲であることを特徴とする建設車両用空気入りタイヤ。 The present invention has been made based on such findings, and the gist thereof is as follows.
(1) In a pneumatic tire for a construction vehicle having a plurality of lug grooves in the lateral region when the tread is divided into a central region and both lateral regions located on both sides in the tire width direction of the central region, In addition, first inclined groove portions extending at a predetermined angle with respect to the tire circumferential direction and second inclined groove portions extending at an angle opposite to the tire circumferential direction are alternately connected. In addition, one zigzag narrow groove continuously extending in a zigzag shape along the tire circumferential direction is provided, and one side extending in the tire circumferential direction through the inner side in the tire width direction of the lug groove in each lateral region. A lateral narrow groove is provided, and the inner side portion of the lug groove in the tire width direction is in a positional relationship facing the vicinity of the connecting portion of the first inclined groove portion and the second inclined groove portion facing the tire width direction, And the tire width direction inner side part of the said lug groove, and the said near connection part In addition, by providing one width direction narrow groove and arranging a zigzag narrow groove, side narrow groove and width direction narrow groove in the tread portion, a plurality of pentagonal or more polygonal block land portions are formed. By forming two rows of polygonal blocks arranged side by side along the tire circumferential direction, and arranging lug grooves and circumferential narrow grooves, a plurality of quadrangular side block land portions are arranged in the tire circumferential direction. The two lug grooves located in the both side regions are formed so that the extending direction from the tire equator side toward the respective tread ends extends from the tire circumferential direction. A pneumatic tire for construction vehicles, which is arranged so as to be inclined at a predetermined angle, and the inclination angle is in a range of 100 to 135 ° measured on an obtuse angle side with respect to the tire circumferential direction.

（２）前記両側方域に位置するラグ溝は、同一タイヤ周方向に対する延在方向が同一である上記（１）に記載の建設車両用空気入りタイヤ。 (2) The pneumatic tire for a construction vehicle according to the above (1), wherein the lug grooves located in the both side regions have the same extending direction with respect to the same tire circumferential direction.

（３）前記両側方域に位置するラグ溝の延在方向は、同一タイヤ周方向に対する傾斜角度が同一である上記（２）に記載の建設車両用空気入りタイヤ。 (3) The pneumatic tire for a construction vehicle according to (2), wherein the extending direction of the lug grooves located in the both side regions has the same inclination angle with respect to the same tire circumferential direction.

（４）前記幅方向細溝の延在方向は、前記ラグ溝の延在方向と同一である上記（１）、（２）又は（３）に記載の建設車両用空気入りタイヤ。 (4) The pneumatic tire for construction vehicles according to (1), (2), or (3), wherein an extending direction of the width direction narrow groove is the same as an extending direction of the lug groove.

（５）前記ジグザグ細溝の溝深さは、ラグ溝の溝深さの70％以上である上記（１）〜（４）のいずれか１項に記載の建設車両用空気入りタイヤ。 (5) The pneumatic tire for a construction vehicle according to any one of (1) to (4), wherein a groove depth of the zigzag narrow groove is 70% or more of a groove depth of the lug groove.

（６）前記ジグザグ細溝の延在形状の振幅は、トレッド幅の5〜30％である上記（１）〜（５）のいずれか１項に記載の建設車両用空気入りタイヤ。 (6) The pneumatic tire for a construction vehicle according to any one of (1) to (5), wherein an amplitude of the extending shape of the zigzag narrow groove is 5 to 30% of a tread width.

（７）前記ジグザグ細溝の溝幅は、ブロック陸部の配設ピッチの3〜8％である上記（１）〜（６）のいずれか１項記載の建設車両用空気入りタイヤ。 (7) The pneumatic tire for a construction vehicle according to any one of (1) to (6), wherein a groove width of the zigzag narrow groove is 3 to 8% of an arrangement pitch of the block land portion.

（８）第１傾斜溝部は、タイヤ周方向に対し20〜50°の角度で延在する上記（１）〜（７）のいずれか１項記載の建設車両用空気入りタイヤ。 (8) The pneumatic tire for a construction vehicle according to any one of (1) to (7), wherein the first inclined groove portion extends at an angle of 20 to 50 ° with respect to the tire circumferential direction.

（９）第２傾斜溝部は、タイヤ周方向に対し−20〜−50°の角度で延在する上記（１）〜（８）のいずれか１項記載の建設車両用空気入りタイヤ。 (9) The pneumatic tire for a construction vehicle according to any one of (1) to (8), wherein the second inclined groove portion extends at an angle of −20 to −50 ° with respect to the tire circumferential direction.

（１０）前記建設車両用空気入りタイヤは、走行時、前記ラグ溝がタイヤ赤道側の端部から接地するように車両装着される上記（１）〜（９）のいずれか１項記載の建設車両用空気入りタイヤ。 (10) The construction according to any one of (1) to (9), wherein the pneumatic tire for a construction vehicle is mounted on the vehicle so that the lug groove is grounded from an end portion on a tire equator side when traveling. Pneumatic tire for vehicles.

本発明によれば、駆動輪及び操舵輪のいずれに用いられる場合であっても、高い耐摩耗性を有し、さらに、発熱性の悪化を抑制できる建設車両用空気入りタイヤを提供することが可能となった。 According to the present invention, it is possible to provide a pneumatic tire for a construction vehicle that has high wear resistance and can suppress deterioration in heat generation, regardless of whether the driving wheel or the steering wheel is used. It has become possible.

本発明の建設車両用空気入りタイヤの一実施形態について、トレッドの一部を模式的に示した図である。It is the figure which showed typically a part of tread about one Embodiment of the pneumatic tire for construction vehicles of this invention. 本発明の建設車両用空気入りタイヤの他の実施形態について、トレッドの一部を模式的に示した図である。It is the figure which showed typically a part of tread about other embodiment of the pneumatic tire for construction vehicles of this invention. 従来の建設車両用空気入りタイヤのトレッドの一部を模式的に示した図である。It is the figure which showed typically a part of tread of the conventional pneumatic tire for construction vehicles. 従来の建設車両用空気入りタイヤのトレッドの一部を模式的に示した図である。It is the figure which showed typically a part of tread of the conventional pneumatic tire for construction vehicles.

以下、本発明の構成と限定理由を、図１〜４を用いて説明する。
図１は、本発明の建設車両用空気入りタイヤの一実施形態について、トレッドの一部を模式的に示した図であり、図２は、本発明の建設車両用空気入りタイヤの他の実施形態について、トレッドの一部を模式的に示した図であり、図３及び図４は、従来の建設車両用空気入りタイヤのトレッドの一部を模式的に示した図である。
なお、図１〜図４については、いずれも、図の矢印Ｃの方向がタイヤ周方向であり、矢印Ｗの方向がタイヤ幅方向である。 Hereinafter, the configuration of the present invention and the reasons for limitation will be described with reference to FIGS.
FIG. 1 is a diagram schematically showing a part of a tread for an embodiment of a pneumatic tire for construction vehicles of the present invention, and FIG. 2 is another embodiment of the pneumatic tire for construction vehicles of the present invention. It is the figure which showed a part of tread typically about the form, and FIG.3 and FIG.4 is the figure which showed a part of tread of the conventional pneumatic tire for construction vehicles.
1 to 4, the direction of arrow C in the figure is the tire circumferential direction, and the direction of arrow W is the tire width direction.

本発明の建設車両用空気入りタイヤは、図１に示すように、トレッド１０を中央域２０と該中央域２０のタイヤ幅方向両側に位置する両側方域３０に区分したときの該側方域３０に、複数本のラグ溝３１を有する建設車両用空気入りタイヤである。ここで、中央域２０とは、タイヤ赤道Ｅを中心として、トレッド幅の25〜75％以下の領域をいい、側方域３０は、トレッドの中央域２０以外の領域をいう。 As shown in FIG. 1, the pneumatic tire for a construction vehicle according to the present invention has the lateral region when the tread 10 is divided into a central region 20 and both lateral regions 30 located on both sides of the central region 20 in the tire width direction. Reference numeral 30 denotes a pneumatic tire for construction vehicles having a plurality of lug grooves 31. Here, the central region 20 refers to a region of 25 to 75% or less of the tread width centered on the tire equator E, and the side region 30 refers to a region other than the central region 20 of the tread.

そして本発明は、図１に示すように、前記中央域２０に、タイヤ周方向に対し所定の角度で延在する第１傾斜溝部２１ａと、該第１傾斜溝部２１ａとはタイヤ周方向に対し逆向きの角度で延在する第２傾斜溝部２１ｂとを交互に連結して、タイヤ周方向に沿ってジグザグ状に連続して延びる１本のジグザグ細溝２１を設け、各側方域３０に、前記ラグ溝３１のタイヤ幅方向内側部３１ａを通り、タイヤ周方向にストレート状に延びる１本の側方細溝３２を設け、前記ラグ溝３１のタイヤ幅方向内側部３１ａが、第１傾斜溝部と第２傾斜溝部の連結部２１ｃ_１、ｃ_２のうちの近い方の連結部２１ｃ_２とタイヤ幅方向に向かい合う配置関係にあり、かつ前記ラグ溝のタイヤ幅方向内側部３１ａと、前記近い方の連結部２１ｃとの間に、連通して延びる１本の幅方向細溝２２を設け、トレッド部１０に、ジグザグ細溝２１、側方細溝３２および幅方向細溝２２を配設することにより、複数個の５角形以上の多角形ブロック陸部２３ａ、２３ｂがタイヤ周方向に沿って並置された２列のブロック列２４ａ、２４ｂを形成し、前記両側方域３０に位置するラグ溝３１は、ともに、タイヤ赤道Ｅ側からそれぞれのトレッド端に向かう延在方向がタイヤ周方向Ｃから所定の角度γ_１、γ_２で傾斜するように配置し、その傾斜角度γ_１、γ_２がタイヤ周方向Ｃに対して鈍角側で測定して100〜135°の範囲であることを特徴とする。 In the present invention, as shown in FIG. 1, in the central region 20, a first inclined groove portion 21a extending at a predetermined angle with respect to the tire circumferential direction, and the first inclined groove portion 21a with respect to the tire circumferential direction. The second inclined groove portions 21b extending at opposite angles are alternately connected, and one zigzag narrow groove 21 extending continuously in a zigzag shape along the tire circumferential direction is provided. The lateral narrow groove 32 extending straight in the tire circumferential direction through the tire width direction inner portion 31a of the lug groove 31 is provided, and the tire width direction inner portion 31a of the lug groove 31 has a first slope. The groove portion and the second inclined groove portion of the connecting portions 21c ₁ , c ₂ are in a positional relationship facing the closer connecting portion 21c ₂ in the tire width direction and close to the tire width direction inner portion 31a of the lug groove. In communication with the connecting portion 21c A plurality of pentagonal or more polygonal blocks are formed by providing one extending widthwise narrow groove 22 and disposing the zigzag narrow groove 21, the side narrow groove 32, and the widthwise narrow groove 22 in the tread portion 10. The land portions 23a, 23b form two block rows 24a, 24b juxtaposed along the tire circumferential direction, and the lug grooves 31 located in the both side regions 30 are both treads from the tire equator E side. The extending direction toward the end is arranged so as to incline at predetermined angles γ ₁ and γ ₂ from the tire circumferential direction C, and the inclination angles γ ₁ and γ ₂ are measured on the obtuse angle side with respect to the tire circumferential direction C. It is characterized by being in the range of 100 to 135 °.

上記構成を具えることで、本発明の多角形ブロック列２４ａ、２４ｂは、タイヤ周方向Ｃにジグザグに延びる前記ジグザグ細溝２１を挟んで各多角形ブロック２３ａ、２３ｂの先端部がタイヤ赤道面Ｅを超えて対向する多角形ブロックに隣接する。それにより、ダンプトラック等の駆動輪として用いられる場合において、走行時、先に踏み込んだ多角形ブロック陸部（図１では多角形ブロック陸部２３ａ）が前記ジグザグ細溝２１を挟んで対向する多角形ブロック陸部２３の一部（図１では多角形ブロック陸部２３ｂの斜線部分）を引き込み、引き込まれた多角形ブロック陸部２３ｂの一部が踏み込む前から変形した状態にあるため、多角形ブロック陸部２３ｂを踏み込んだ瞬間から路面と引き込まれた多角形ブロック陸部と２３ｂの間に剪断力が発生し、トラクションを向上させることが可能となる。その結果、トラクションの向上によって、摩耗の主要因となるタイヤの蹴り出し時の剪断力を低減できるため、駆動輪として用いた場合の耐摩耗性が向上する。 By providing the above-described configuration, the polygon block rows 24a and 24b of the present invention are arranged such that the tip portions of the polygon blocks 23a and 23b sandwich the zigzag narrow groove 21 extending zigzag in the tire circumferential direction C. Adjacent to the opposing polygonal block beyond E. As a result, when used as a drive wheel for a dump truck or the like, the polygon block land portion (the polygon block land portion 23a in FIG. 1) that has been stepped on first when traveling is opposed across the zigzag narrow groove 21. Since a part of the rectangular block land portion 23 (in FIG. 1, the hatched portion of the polygonal block land portion 23b) is pulled in, and a part of the drawn polygonal block land portion 23b is in a deformed state before it is stepped on, the polygon From the moment when the block land portion 23b is stepped on, a shearing force is generated between the road surface and the polygonal block land portion 23b that has been pulled in, and traction can be improved. As a result, by improving the traction, it is possible to reduce the shearing force at the time of kicking out the tire, which is a main cause of wear, so that the wear resistance when used as a drive wheel is improved.

さらに、前記各ラグ溝３１を、タイヤ周方向Ｃから100〜135°で傾斜するように配置することで、本発明のタイヤを前記ラグ溝３１がセンター側から接地していくように建設車両に装着した場合には、タイヤの踏み込み時に各側方ブロック陸部３３ａ、３３ｂがショルダー側（タイヤ幅方向Ｗ外側）に変形し、蹴り出し時に元の形状に戻る（センター側に戻る）ため、摩耗の原因となるセンター側に変形した踏面が蹴り出し時にショルダー側に戻る動きを打ち消すことができる。その結果、本発明の建設車両用空気入りタイヤは、操舵輪として用いた場合であっても、摩耗を有効に抑制することができる。 Furthermore, by arranging the lug grooves 31 so as to be inclined at 100 to 135 ° from the tire circumferential direction C, the tire of the present invention can be attached to a construction vehicle so that the lug grooves 31 are grounded from the center side. When worn, the side block land portions 33a, 33b are deformed to the shoulder side (outer side in the tire width direction W) when the tire is depressed, and return to the original shape (returns to the center side) when kicked out. It is possible to cancel the movement of the tread that has been deformed toward the center causing the back to the shoulder when kicking out. As a result, the pneumatic tire for construction vehicles of the present invention can effectively suppress wear even when used as a steering wheel.

ここで、前記ラグ溝３１の傾斜角度を100〜130°としたのは、傾斜角度が100°未満の場合、踏み込み時のタイヤ幅方向外側外側への変形が小さくなるため、前記センター側に変形した踏面が蹴り出し時にショルダー側に戻る動きを十分に打ち消すことができず、摩耗の原因となるからであり、一方、傾斜角度が130°を超えると、ラグ溝３１の形状が細長くなるため、ラグ剛性が悪化し、耐摩耗性が低下するからである。 Here, the angle of inclination of the lug groove 31 is set to 100 to 130 °. When the angle of inclination is less than 100 °, the deformation toward the outer side in the tire width direction when the pedal is stepped down becomes small. This is because the movement of the tread surface that returns to the shoulder side when kicking out cannot be sufficiently canceled out, causing wear, and on the other hand, if the inclination angle exceeds 130 °, the shape of the lug groove 31 becomes elongated. This is because the lug rigidity deteriorates and the wear resistance decreases.

また、本発明の空気入りタイヤは、操舵輪として用いた場合に上述の耐摩耗性を得る点から、走行時（図１では、下が踏み込み側（地面）で、回転方向Ｙにて走行。）、前記ラグ溝３１がタイヤ赤道Ｅ側の端部から接地するように車両装着する必要がある。 In addition, the pneumatic tire of the present invention travels in the rotational direction Y when traveling (in FIG. 1, the lower side is the stepping side (ground) in view of obtaining the above-mentioned wear resistance when used as a steering wheel. ), It is necessary to mount the vehicle so that the lug groove 31 is grounded from the end on the tire equator E side.

なお、従来のトレッド１００では、図３に示すように、タイヤ周方向に沿った直線状のジグザグ細溝２１０を挟んで多角形ブロック陸部２３０が設けられているため、走行時、上述したような、引き込まれた多角形ブロックと路面との剪断力によるトラクションの向上はなく、十分に耐摩耗性の向上が図れないと考えられる。 In the conventional tread 100, as shown in FIG. 3, since the polygonal block land portion 230 is provided across the linear zigzag narrow groove 210 along the tire circumferential direction, as described above during traveling. Further, there is no improvement in traction due to the shearing force between the drawn polygonal block and the road surface, and it is considered that the wear resistance cannot be sufficiently improved.

また、図４に示すように、タイヤ周方向に沿ったジグザグ溝２１を配設している空気入りタイヤであっても、前記ラグ溝３１が、延在方向がタイヤ周方向Ｃから100〜135°で傾斜するように配置されていないため、操舵輪として用いられた場合、摩耗の原因となるセンター側に変形した踏面が蹴り出し時にショルダー側に戻る動きを打ち消すことができず、十分な耐摩耗性を発揮することができない。 Moreover, as shown in FIG. 4, even if it is the pneumatic tire which has arrange | positioned the zigzag groove | channel 21 along a tire circumferential direction, the said lug groove 31 is 100-135 from the tire circumferential direction C in the extending direction. When it is used as a steered wheel, the tread that has been deformed to the center side, which causes wear, can not cancel the movement back to the shoulder side when kicking out, providing sufficient resistance. Abrasion cannot be demonstrated.

さらに、図２に示すように、前記両側方域３０に位置するラグ溝３１の延在方向は、同一のタイヤ周方向（回転方向Ｙ）に対する方向が同じである。上述の、摩耗の原因となるセンター側に変形した踏面が蹴り出し時にショルダー側に戻る動きを打ち消す効果が有効に発揮されるためである。なお、傾斜角度δ_１、δ_２については、必ずしも同じである必要はない。 Further, as shown in FIG. 2, the extending direction of the lug grooves 31 located in the both side regions 30 is the same with respect to the same tire circumferential direction (rotational direction Y). This is because the above-described effect of canceling the movement of the tread deformed to the center side that causes wear back to the shoulder side when kicking out is effectively exhibited. Note that the inclination angles δ ₁ and δ ₂ are not necessarily the same.

さらにまた、図２に示すように、前記幅方向細溝２２の延在方向は、前記ラグ溝３１の延在方向と同一であることが好ましい。前記幅方向細溝２２の傾斜によって、前記ブロック陸部２３ａ、２３ｂについても、前記側方ブロック陸部３３ａ、３３ｂと同様に、タイヤの踏み込み時に各側方ブロック陸部２３ａ、２３ｂがショルダー側（タイヤ幅方向Ｗ外側）に変形し、蹴り出し時に元の形状に戻る（センター側に戻る）ため、操舵輪として用いた場合の摩耗の原因である、タイヤが回転して踏み込んでいく際にセンター側に変形した踏面が蹴り出し時にショルダー側に戻る動きを打ち消すことができる。その結果、本発明の建設車両用空気入りタイヤは、操舵輪として用いた場合であっても、摩耗を有効に抑制することができるからである。
なお、前記幅方向細溝２２は、ＴＲＡの正規リムにリム組みし、ＴＲＡの正規内圧充填後、ＴＲＡの正規荷重（100％）をかけた状態でタイヤが接地した時には、溝が閉じられており、所望のブロック剛性を確保することができる。 Furthermore, as shown in FIG. 2, it is preferable that the extending direction of the width direction narrow groove 22 is the same as the extending direction of the lug groove 31. As with the side block land portions 33a and 33b, the side block land portions 23a and 23b are moved to the shoulder side when the tire is stepped on, as with the side block land portions 33a and 33b. Tire width direction W outside), and when it kicks out, it returns to its original shape (returns to the center side), which causes wear when used as a steering wheel. It is possible to cancel the movement of the tread deformed to the side back to the shoulder when kicking out. As a result, the pneumatic tire for construction vehicles of the present invention can effectively suppress wear even when used as a steering wheel.
The width direction narrow groove 22 is assembled with a TRA regular rim, and when the tire is grounded with the TRA regular load (100%) applied after filling the TRA regular internal pressure, the groove is closed. Thus, a desired block rigidity can be ensured.

また、本発明では、前記ジグザグ細溝２１は、前記中央域２０に、前記第１傾斜溝部２１ａと、前記第２傾斜溝部２１ｂとを交互に連結して、タイヤ周方向に沿ってジグザグ状に連続して延びる溝であり、その他構成については、特に限定はしないが、その溝深さは、ラグ溝の溝深さの70％以上であることが好ましい。ジグザグ細溝２１の溝深さが70％未満の場合、タイヤ使用末期にはトレッドが摩耗し、ジグザグ細溝２１が消失して、十分に本発明の効果を発揮できない恐れがあり、細溝による空冷効果がなくなる結果、トレッドが発熱して故障を発生する恐れがあるからである。 In the present invention, the zigzag narrow groove 21 is formed in a zigzag shape along the tire circumferential direction by alternately connecting the first inclined groove portion 21a and the second inclined groove portion 21b to the central region 20. The groove extends continuously, and other configurations are not particularly limited, but the groove depth is preferably 70% or more of the groove depth of the lug groove. If the groove depth of the zigzag narrow groove 21 is less than 70%, the tread may be worn out at the end of use of the tire, and the zigzag narrow groove 21 may disappear, and the effects of the present invention may not be sufficiently exerted. This is because the air cooling effect is lost, and as a result, the tread may generate heat and cause a failure.

図１に示すように、前記ジグザグ細溝２１の延在形状の振幅ｗ１は、トレッド幅ＴＷの5〜30％であるが好ましい。前記振幅ｗ１が5％未満の場合、前記多角形ブロック２３の一部を引き込むための力が小さくなり、十分にトラクションを向上させることができず、十分に耐摩耗性の向上が図れない恐れがあるからであり、一方、前記振幅ｗ１が30％を超えると、センター部のブロック剛性が低下し、摩耗性の向上が図れなくなるためである。 As shown in FIG. 1, the amplitude w1 of the extending shape of the zigzag narrow groove 21 is preferably 5 to 30% of the tread width TW. When the amplitude w1 is less than 5%, the force for drawing a part of the polygonal block 23 becomes small, the traction cannot be improved sufficiently, and the wear resistance may not be improved sufficiently. On the other hand, if the amplitude w1 exceeds 30%, the block rigidity of the center portion is lowered and the wearability cannot be improved.

さらに、前記第１傾斜溝部２１ａは、タイヤ周方向に対し20〜50°の角度αで延在することが好ましい。角度αが20°未満の場合前記多角形ブロック２３の一部を引き込むための力が小さくなり、十分にトラクションを向上させることができず、十分に耐摩耗性の向上が図れない恐れがある一方、50°を超えると、センター部のブロック剛性が低下し、摩耗性の向上が図れなくなるためである。
また、同様の理由で、前記第２傾斜溝部２１ｂは、タイヤ周方向に対し−20〜−50°の角度βで延在することが好ましい。
なお、本発明では、前記傾斜部２１ａ、２１ｂの傾斜角度とは、図１に示すように、設置面を下としたとき、タイヤ周方向Ｃに対して時計回りの角度を正の角度とし、反時計回りの角度を負の角度として表わしている。 Further, the first inclined groove portion 21a preferably extends at an angle α of 20 to 50 ° with respect to the tire circumferential direction. When the angle α is less than 20 °, the force for drawing a part of the polygonal block 23 becomes small, the traction cannot be sufficiently improved, and the wear resistance may not be sufficiently improved. If the angle exceeds 50 °, the block rigidity of the center portion decreases, and the wear resistance cannot be improved.
For the same reason, the second inclined groove 21b preferably extends at an angle β of −20 to −50 ° with respect to the tire circumferential direction.
In the present invention, the inclination angles of the inclined portions 21a and 21b are, as shown in FIG. 1, when the installation surface is downward, the clockwise angle with respect to the tire circumferential direction C is a positive angle, The counterclockwise angle is represented as a negative angle.

さらにまた、図１に示すように、前記ジグザグ細溝２１の溝幅ｗ２は、前記ブロック陸部２３の配設ピッチＡの3〜8％であることが好ましい。ジグザグ細溝２１の溝幅ｗ２が配設ピッチの3％未満の場合、溝幅が狭すぎるために、放熱効果が得られなくなり、発熱性の悪化を引き起こす恐れがあるからであり、一方、前記溝幅ｗ２が8％を超えると、前記多角形ブロック２３の一部を引き込むための力が小さくなり、十分にトラクションを向上させることができず、十分に耐摩耗性の向上が図れない恐れがあるからである。
なお、前記ジグザグ細溝２１は、ＴＲＡの正規リムにリム組みし、ＴＲＡの正規内圧充填後、ＴＲＡの正規荷重（100％）をかけた状態でタイヤが接地した時には、溝が閉じられており、所望のブロック剛性を確保することができる。 Furthermore, as shown in FIG. 1, the groove width w <b> 2 of the zigzag narrow groove 21 is preferably 3 to 8% of the arrangement pitch A of the block land portion 23. This is because, when the groove width w2 of the zigzag narrow groove 21 is less than 3% of the arrangement pitch, the groove width is too narrow, so that the heat dissipation effect cannot be obtained and the heat generation may be deteriorated. If the groove width w2 exceeds 8%, the force for pulling in a part of the polygonal block 23 becomes small, the traction cannot be improved sufficiently, and the wear resistance may not be improved sufficiently. Because there is.
The zigzag narrow groove 21 is closed when the tire is grounded with the TRA's regular load (100%) applied after the TRA is assembled to the TRA's regular rim and the TRA's regular internal pressure is filled. The desired block rigidity can be ensured.

なお、前記側方細溝３２は、前記ラグ溝３１のタイヤ幅方向内側部３１ａを通り、タイヤ周方向に延びる溝であり、その構成については、特に限定はしない。ここで、前記ラグ溝３１のタイヤ幅方向内側部３１ａとは、前記ラグ溝３１の、溝幅が縮小し始める位置からタイヤ幅方向内側先端までの部分をいう。 In addition, the said side narrow groove 32 is a groove | channel extended in the tire circumferential direction through the tire width direction inner side part 31a of the said lug groove 31, and it does not specifically limit about the structure. Here, the tire width direction inner side portion 31a of the lug groove 31 refers to a portion of the lug groove 31 from the position where the groove width starts to decrease to the inner end in the tire width direction.

また、前記幅方向細溝２２は、前記ラグ溝３１のタイヤ幅方向内側部３１ａと、前記近い方の前記ジグザグ細溝２１の連結部２１ｃ_２との間に、連通して延びる溝であり、その他の構成については、特に限定はしない。
ただし、前記幅方向細溝２２は、前記ジグザグ細溝２１と同様に、その溝幅が前記ブロック陸部２３の配設ピッチＡの3〜8％であることが好ましい。前記幅方向細溝２２の溝幅が配設ピッチの3％未満の場合、溝幅が狭すぎるために、放熱効果が得られなくなり、発熱性の悪化を引き起こす恐れがあるからであり、一方、前記溝幅が8％を超えると、前記多角形ブロック２３の一部を引き込むための力が小さくなり、十分にトラクションを向上させることができず、十分に耐摩耗性の向上が図れない恐れがあるからである。 Also, the width-direction narrow grooves 22, and a tire width direction inner side portion 31a of the lug groove 31, between the connecting portion 21c ₂ of the closer of the zigzag narrow groove 21, a groove extending in communication, Other configurations are not particularly limited.
However, like the zigzag narrow groove 21, the width direction narrow groove 22 is preferably 3 to 8% of the arrangement pitch A of the block land portions 23. When the groove width of the width direction narrow groove 22 is less than 3% of the arrangement pitch, since the groove width is too narrow, a heat dissipation effect cannot be obtained, and heat generation may be deteriorated. If the groove width exceeds 8%, the force for drawing a part of the polygonal block 23 becomes small, the traction cannot be improved sufficiently, and the wear resistance may not be improved sufficiently. Because there is.

なお、前記ジグザグ細溝２１、側方細溝３２、ラグ溝３１及び幅方向細溝２２によって区画成形される５角形以上の前記多角形ブロック陸部２３は、図１に示すように、タイヤ周方向ｃに沿って並置されることで２列のブロック列２４ａ、２４ｂを形成する。 In addition, the polygonal block land portion 23 having a pentagon or more formed by the zigzag narrow groove 21, the side narrow groove 32, the lug groove 31, and the width direction narrow groove 22 has a tire circumference as shown in FIG. Two block rows 24a and 24b are formed by being juxtaposed along the direction c.

また、前記多角形ブロック陸部２３は、５角形以上であれば特に限定はされず、ラグ溝３１のタイヤ幅方向内側部３１ａの形状によって、例えば、図１に示すように、７角形の多角形ブロックとすることもでき、図２に示すように、６角形の多角形ブロック陸部２３とすることもでき、５角形の多角形ブロック陸部２３とすることもできる。
なお、５角形、６角形又は７角形のいずれの場合であっても、トラクションの向上によって、摩耗の主要因となるタイヤの蹴り出し時の剪断力を低減し、耐摩耗性の向上を図ることができる。 Further, the polygonal block land portion 23 is not particularly limited as long as it is a pentagon or more. Depending on the shape of the lug groove 31 in the tire width direction inner portion 31a, for example, as shown in FIG. It can also be a square block, and as shown in FIG. 2, it can be a hexagonal polygonal block land portion 23 or a pentagonal polygonal block land portion 23.
Whether it is pentagonal, hexagonal or heptagonal, to improve the traction, reduce the shear force when kicking the tire, which is the main factor of wear, and improve the wear resistance. Can do.

上述したところは、この発明の実施形態の一例を示したにすぎず、請求の範囲において種々の変更を加えることができる。 The above description is merely an example of the embodiment of the present invention, and various modifications can be made within the scope of the claims.

（実施例１）
実施例として、タイヤサイズが46／90 R 57であり、図１に示すように、トレッド１０の側方域３０に、複数本のラグ溝３１を有し、前記中央域２０に、タイヤ周方向に対し所定の角度（表１）で延在する第１傾斜溝部２１ａと、該第１傾斜溝部２１ａとはタイヤ周方向に対し逆向きの角度（表１）で延在する第２傾斜溝部２１ｂとを交互に連結して、タイヤ周方向に沿ってジグザグ状に連続して延びる１本のジグザグ細溝２１を設け、各側方域３０に、前記ラグ溝３１のタイヤ幅方向内側部３１ａを通り、タイヤ周方向に延びる１本の側方細溝３２を設け、前記ラグ溝３１のタイヤ幅方向内側部３１ａが、第１傾斜溝部と第２傾斜溝部の連結部２１ｃのうちの近い方の連結部２１ｃとタイヤ幅方向に向かい合う配置関係にあり、かつ前記ラグ溝のタイヤ幅方向内側部３１ａと、前記近い方の連結部２１ｃとの間に、連通して延びる１本の幅方向細溝２２を設け、トレッド部１０に、ジグザグ細溝２１、側方細溝３２および幅方向細溝２２を配設することにより、複数個の多角形のブロック陸部２３（図１では左側のブロック陸部２３ａが６角形、右側のブロック陸部２３ｂが７角形）がタイヤ周方向に沿って並置された２列のブロック列２４ａ、ｂを形成し、前記両側方域３０に位置するラグ溝３１は、ともに、タイヤ赤道Ｅ側からそれぞれのトレッド端に向かう延在方向が同一のタイヤ周方向（回転方向Ｙ）から所定の角度γ_１、γ_２で傾斜するように配置した空気入りタイヤを、サンプルとして作製した。
なお、空気入りタイヤの、ラグ溝３１の溝深さ（mm）、ジグザグ細溝２１の溝深さ（mm）、ラグ溝３１の溝深さに対するジグザグ細溝２１の溝深さ（％）、トレッド幅に対するジグザグの延在形状の振幅（％）、タイヤ周方向Ｃに対する第１傾斜溝部２１ａ、第２傾斜溝部２１ａの角度（°）、タイヤ周方向Ｃに対するラグ溝３１の角度（°）及びタイヤ周方向Ｃに対する幅方向細溝２２の角度（°）については、表１に示す。 Example 1
As an example, the tire size is 46/90 R 57, and as shown in FIG. 1, the tread 10 has a plurality of lug grooves 31 in the lateral region 30, and the central region 20 has a tire circumferential direction. First inclined groove portion 21a extending at a predetermined angle (Table 1), and second inclined groove portion 21b extending from the first inclined groove portion 21a at an angle (Table 1) opposite to the tire circumferential direction. Are alternately connected, one zigzag narrow groove 21 extending continuously in a zigzag shape along the tire circumferential direction is provided, and the inner side 31a in the tire width direction of the lug groove 31 is provided in each side region 30. As described above, one side narrow groove 32 extending in the tire circumferential direction is provided, and the inner side 31a in the tire width direction of the lug groove 31 is closer to the connection portion 21c between the first inclined groove portion and the second inclined groove portion. The lug groove is in a positional relationship facing the connecting portion 21c in the tire width direction. Between the tire width direction inner side portion 31a and the closer connecting portion 21c, one width direction narrow groove 22 extending in communication is provided, and the tread portion 10 has a zigzag narrow groove 21 and a side narrow groove 32. By arranging the width direction narrow grooves 22, a plurality of polygonal block land portions 23 (in FIG. 1, the left block land portion 23a is a hexagon and the right block land portion 23b is a heptagon) The lug grooves 31 that form two block rows 24a, b juxtaposed along the direction and are located in the both side regions 30 have the same extending direction from the tire equator E side toward the respective tread ends. A pneumatic tire arranged so as to be inclined at predetermined angles γ ₁ and γ ₂ from the tire circumferential direction (rotation direction Y) was prepared as a sample.
In the pneumatic tire, the groove depth (mm) of the lug groove 31, the groove depth (mm) of the zigzag narrow groove 21, the groove depth (%) of the zigzag narrow groove 21 with respect to the groove depth of the lug groove 31, The amplitude (%) of the zigzag extending shape with respect to the tread width, the angle (°) of the first inclined groove portion 21a and the second inclined groove portion 21a with respect to the tire circumferential direction C, the angle (°) of the lug groove 31 with respect to the tire circumferential direction C, and Table 1 shows the angle (°) of the width direction narrow groove 22 with respect to the tire circumferential direction C.

（実施例２）
実施例２として、図２に示すように、前記両側方域３０に位置するラグ溝３１の延在方向が、幅方向細溝２２のタイヤ周方向Ｃに対する傾斜角度δ_１、δ_２と同一であること以外は、実施例１と同様の条件によって、サンプルを作製した。
なお、空気入りタイヤの、ラグ溝３１の溝深さ（mm）、ジグザグ細溝２１の溝深さ（mm）、ラグ溝３１の溝深さに対するジグザグ細溝２１の溝深さ（％）、トレッド幅に対するジグザグの延在形状の振幅（％）、タイヤ周方向Ｃに対する第１傾斜溝部２１ａ、第２傾斜溝部２１ａの角度（°）、タイヤ周方向Ｃに対するラグ溝３１の角度（°）及びタイヤ周方向Ｃに対する幅方向細溝２２の角度（°）については、表１に示す。 (Example 2)
As Example 2, as shown in FIG. 2, the extending direction of the lug groove 31 located in the both side regions 30 is the same as the inclination angles δ ₁ and δ _{2 of} the width direction narrow groove 22 with respect to the tire circumferential direction C. A sample was prepared under the same conditions as in Example 1 except that there was.
In the pneumatic tire, the groove depth (mm) of the lug groove 31, the groove depth (mm) of the zigzag narrow groove 21, the groove depth (%) of the zigzag narrow groove 21 with respect to the groove depth of the lug groove 31, The amplitude (%) of the zigzag extending shape with respect to the tread width, the angle (°) of the first inclined groove portion 21a and the second inclined groove portion 21a with respect to the tire circumferential direction C, the angle (°) of the lug groove 31 with respect to the tire circumferential direction C, and Table 1 shows the angle (°) of the width direction narrow groove 22 with respect to the tire circumferential direction C.

（比較例１）
比較例１は、図３に示すように、ジグザグではなく、タイヤ周方向に沿って直線状に延びる中央細溝２１０を挟んで多角形ブロック陸部２３０が設けられている、従来のトレッド１００を具えること以外は、実施例１と同様の条件のタイヤをサンプルとして用いた。
なお、空気入りタイヤの、ラグ溝３１０の溝深さ（mm）、中央細溝２１０の溝深さ（mm）、ラグ溝３１０の溝深さに対する中央細溝２１０の溝深さ（％）、タイヤ周方向Ｃに対するラグ溝３１０の角度（°）及びタイヤ周方向Ｃに対する幅方向細溝２２０の角度（°）については、表１に示す。 (Comparative Example 1)
As shown in FIG. 3, the comparative example 1 is not a zigzag but a conventional tread 100 in which a polygonal block land portion 230 is provided with a central narrow groove 210 extending linearly along the tire circumferential direction. A tire having the same conditions as in Example 1 was used as a sample except that it was provided.
In the pneumatic tire, the groove depth (mm) of the lug groove 310, the groove depth (mm) of the central narrow groove 210, the groove depth (%) of the central thin groove 210 with respect to the groove depth of the lug groove 310, Table 1 shows the angle (°) of the lug groove 310 with respect to the tire circumferential direction C and the angle (°) of the width direction narrow groove 220 with respect to the tire circumferential direction C.

（比較例２）
比較例２は、図４に示すように、前記両側方域３０に位置する少なくとも一方のラグ溝３１の延在方向が、同一タイヤ周方向Ｃ（回転方向Ｙ）に対し、鈍角側で測定して70°、110°であること以外は、実施例１と同様の条件によって、サンプルを作製した。
なお、空気入りタイヤの、ラグ溝３１の溝深さ（mm）、ジグザグ細溝２１の溝深さ（mm）、ラグ溝３１の溝深さに対するジグザグ細溝２１の溝深さ（％）、トレッド幅に対するジグザグの延在形状の振幅（％）、タイヤ周方向Ｃに対する第１傾斜溝部２１ａ、第２傾斜溝部２１ａの角度（°）、タイヤ周方向Ｃに対するラグ溝３１の角度（°）及びタイヤ周方向Ｃに対する幅方向細溝２２の角度（°）については、表１に示す。 (Comparative Example 2)
In Comparative Example 2, as shown in FIG. 4, the extending direction of at least one lug groove 31 located in the both side regions 30 is measured on the obtuse angle side with respect to the same tire circumferential direction C (rotation direction Y). Samples were prepared under the same conditions as in Example 1 except that they were 70 ° and 110 °.
In the pneumatic tire, the groove depth (mm) of the lug groove 31, the groove depth (mm) of the zigzag narrow groove 21, the groove depth (%) of the zigzag narrow groove 21 with respect to the groove depth of the lug groove 31, The amplitude (%) of the zigzag extending shape with respect to the tread width, the angle (°) of the first inclined groove portion 21a and the second inclined groove portion 21a with respect to the tire circumferential direction C, the angle (°) of the lug groove 31 with respect to the tire circumferential direction C, and Table 1 shows the angle (°) of the width direction narrow groove 22 with respect to the tire circumferential direction C.

（比較例３）
また、比較例３は、図示しないが、前記両側方域３０に位置するラグ溝３１の延在方向が、いずれも同一タイヤ周方向Ｃ（回転方向Ｙ）に対し、140°であること以外は、実施例１と同様の条件によって、サンプルを作製した。
なお、空気入りタイヤの、ラグ溝３１の溝深さ（mm）、ジグザグ細溝２１の溝深さ（mm）、ラグ溝３１の溝深さに対するジグザグ細溝２１の溝深さ（％）、トレッド幅に対するジグザグの延在形状の振幅（％）、タイヤ周方向Ｃに対する第１傾斜溝部２１ａ、第２傾斜溝部２１ａの角度（°）、タイヤ周方向Ｃに対するラグ溝３１の角度（°）及びタイヤ周方向Ｃに対する幅方向細溝２２の角度（°）については、表１に示す。 (Comparative Example 3)
Moreover, although the comparative example 3 is not shown in figure, the extending direction of the lug groove 31 located in the both-sides region 30 is 140 degrees with respect to the same tire circumferential direction C (rotation direction Y). Samples were prepared under the same conditions as in Example 1.
In the pneumatic tire, the groove depth (mm) of the lug groove 31, the groove depth (mm) of the zigzag narrow groove 21, the groove depth (%) of the zigzag narrow groove 21 with respect to the groove depth of the lug groove 31, The amplitude (%) of the zigzag extending shape with respect to the tread width, the angle (°) of the first inclined groove portion 21a and the second inclined groove portion 21a with respect to the tire circumferential direction C, the angle (°) of the lug groove 31 with respect to the tire circumferential direction C, and Table 1 shows the angle (°) of the width direction narrow groove 22 with respect to the tire circumferential direction C.

（評価１）
実施例１〜２及び比較例１〜３の空気入りタイヤを、ＴＲＡの正規リムにリム組みし、ＴＲＡの正規内圧充填後、車両に前輪（操舵輪）として装着し、市場を走行させた後、トレッドの所定位置（トレッド幅に対し、センターから25％外側位置）での溝深さ（mm）を測定することにより、耐摩耗性の評価を行った。結果を表２に示す。
なお、評価結果は、比較例１のタイヤの耐摩耗性を100％としたときの相対比（％）によって表わし、数値（％）が大きいほど良好な結果となる。 (Evaluation 1)
After the pneumatic tires of Examples 1 and 2 and Comparative Examples 1 to 3 are assembled on a regular rim of TRA, and after the regular internal pressure of TRA is filled, the vehicle is mounted as a front wheel (steering wheel) and traveled in the market. The wear resistance was evaluated by measuring the groove depth (mm) at a predetermined position of the tread (a position 25% outside the center with respect to the tread width). The results are shown in Table 2.
The evaluation result is represented by a relative ratio (%) when the wear resistance of the tire of Comparative Example 1 is 100%, and the larger the numerical value (%), the better the result.

（評価２）
実施例１〜２及び比較例１〜３の空気入りタイヤを、ＴＲＡの正規リムにリム組みし、ＴＲＡの正規内圧充填後、車両に後輪（駆動輪）として装着し、市場を走行させた後、トレッドの所定位置（トレッド幅に対し、センターから25％外側位置）での溝深さ（mm）を測定することにより、耐摩耗性の評価を行った。結果を表２に示す。
なお、評価結果は、比較例１のタイヤの耐摩耗性を100％としたときの相対比（％）によって表わし、数値（％）が大きいほど良好な結果となる。 (Evaluation 2)
The pneumatic tires of Examples 1 and 2 and Comparative Examples 1 to 3 were assembled on a regular rim of TRA, and after the regular internal pressure of TRA was filled, the vehicle was mounted on the vehicle as a rear wheel (drive wheel), and the market was run Then, the wear resistance was evaluated by measuring the groove depth (mm) at a predetermined position of the tread (25% outside the center with respect to the tread width). The results are shown in Table 2.
The evaluation result is represented by a relative ratio (%) when the wear resistance of the tire of Comparative Example 1 is 100%, and the larger the numerical value (%), the better the result.

（評価３）
実施例１、実施例２及び比較例１の空気入りタイヤを、ＴＲＡの正規リムにリム組みし、ＴＲＡの正規内圧充填後、ＴＲＡの正規荷重（100％）をかけた状態で、試験速度8km／hで24時間、室内ドラム試験を行い、トレッドセンター部の温度測定を行うことで発熱性の評価を行った。結果を表２に示す。
なお、評価結果は、比較例１のタイヤの発熱性を100としたときの相対温度（℃）によって表わし、数値（℃）が低いほど良好な結果となる。 (Evaluation 3)
The pneumatic tires of Example 1, Example 2 and Comparative Example 1 were assembled on a TRA regular rim, filled with TRA regular internal pressure, and then loaded with TRA regular load (100%), with a test speed of 8 km. An indoor drum test was conducted for 24 hours at / h, and the heat generation was evaluated by measuring the temperature of the tread center. The results are shown in Table 2.
The evaluation result is represented by the relative temperature (° C.) when the heat generation property of the tire of Comparative Example 1 is 100, and the lower the numerical value (° C.), the better the result.

表２の結果より、本発明による空気入りタイヤである実施例１及び２については、いずれも、従来のトレッドを具える空気入りタイヤである比較例１に比べて、前輪及び後輪に用いられた場合の耐摩耗性が10％以上向上していることがわかった。また、発熱性についても低減できていることがわかり、本発明による空気入りタイヤは、従来のものに比べて、高い耐摩耗性を有し、さらに、発熱性の悪化を抑制できることがわかった。なお、ジグザグ溝を設けた比較例２については、後輪として用いた場合には、高い耐摩耗性を有するものの、前輪として用いた場合には、対摩耗性の効果がないことがわかる。また、比較例３については、前輪・後輪のいずれに用いられる場合でも耐摩耗性が低いことがわかる。 From the results of Table 2, both Examples 1 and 2 which are pneumatic tires according to the present invention are used for the front and rear wheels as compared with Comparative Example 1 which is a pneumatic tire having a conventional tread. It has been found that the wear resistance is improved by 10% or more. Moreover, it turned out that it can also reduce about heat_generation | fever, The pneumatic tire by this invention has high abrasion resistance compared with the conventional one, and also it turned out that the deterioration of heat generation can be suppressed. Note that Comparative Example 2 provided with the zigzag grooves has high wear resistance when used as a rear wheel, but has no wear resistance effect when used as a front wheel. Further, it can be seen that Comparative Example 3 has low wear resistance when used for either the front wheel or the rear wheel.

本発明によれば、駆動輪及び操舵輪のいずれに用いられる場合であっても、高い耐摩耗性を有し、さらに、発熱性の悪化を抑制できる建設車両用空気入りタイヤを提供することが可能である。 According to the present invention, it is possible to provide a pneumatic tire for a construction vehicle that has high wear resistance and can suppress deterioration in heat generation, regardless of whether the driving wheel or the steering wheel is used. Is possible.

１０トレッド
２０、２００中央域
２１、２１０ジグザグ細溝
２２、２２０幅方向細溝
２３、２３０多角形ブロック陸部
２４多角形ブロック列
３０、３００側方域
３１、３１０ラグ溝
３２、３２０側方細溝
３３側方ブロック陸部
３４側方ブロック列 10 Tread 20, 200 Central region 21, 210 Zigzag narrow groove 22, 220 Width direction narrow groove 23, 230 Polygon block land 24 Polygon block row 30, 300 Side region 31, 310 Lug groove 32, 320 Side narrow Groove 33 Side block land 34 Side block row

Claims

In a pneumatic tire for a construction vehicle having a plurality of lug grooves in the lateral region when the tread is divided into a central region and both lateral regions located on both sides in the tire width direction of the central region,
In the central region, first inclined groove portions extending at a predetermined angle with respect to the tire circumferential direction and second inclined groove portions extending at an angle opposite to the tire circumferential direction are alternately arranged. Connected, provided with one zigzag narrow groove extending continuously in a zigzag shape along the tire circumferential direction,
In each lateral region, one lateral narrow groove extending in the tire circumferential direction through the tire width direction inner portion of the lug groove is provided,
The inner portion of the lug groove in the tire width direction is in a positional relationship facing the vicinity of the connecting portion of the first inclined groove portion and the second inclined groove portion facing the tire width direction, and the tire width of the lug groove Provide one width direction narrow groove between the direction inner portion and the closer connecting portion,
By arranging zigzag narrow grooves, side narrow grooves and width direction narrow grooves in the tread portion, a plurality of pentagonal or more polygonal block land portions are juxtaposed along the tire circumferential direction. Two rows of side blocks in which a plurality of quadrilateral or more side block land portions are juxtaposed along the tire circumferential direction by forming a polygonal block row and arranging lug grooves and circumferential narrow grooves Forming a column,
The lug grooves located in the both side regions are arranged so that the extending direction from the tire equator side toward each tread end is inclined at a predetermined angle from the tire circumferential direction, and the inclination angle is in the tire circumferential direction. A pneumatic tire for construction vehicles, characterized in that it is in the range of 100 to 135 ° measured on the obtuse angle side.

The pneumatic tire for a construction vehicle according to claim 1, wherein the lug grooves positioned in the both side regions have the same extending direction with respect to the same tire circumferential direction.

The pneumatic tire for a construction vehicle according to claim 2, wherein the extending direction of the lug grooves located in the both side regions has the same inclination angle with respect to the same tire circumferential direction.

The pneumatic tire for a construction vehicle according to claim 1, 2 or 3, wherein the extending direction of the widthwise narrow groove is the same as the extending direction of the lug groove.

The pneumatic tire for construction vehicles according to any one of claims 1 to 4, wherein a groove depth of the zigzag narrow groove is 70% or more of a groove depth of the lug groove.

The pneumatic tire for a construction vehicle according to any one of claims 1 to 5, wherein an amplitude of the extending shape of the zigzag narrow groove is 5 to 30% of a tread width.

The pneumatic tire for a construction vehicle according to any one of claims 1 to 6, wherein a groove width of the zigzag narrow groove is 3 to 8% of an arrangement pitch of the block land portion.

The pneumatic tire for construction vehicles according to any one of claims 1 to 7, wherein the first inclined groove portion extends at an angle of 20 to 50 ° with respect to the tire circumferential direction.

The pneumatic tire for a construction vehicle according to any one of claims 1 to 8, wherein the second inclined groove portion extends at an angle of -20 to -50 degrees with respect to the tire circumferential direction.

The pneumatic tire for a construction vehicle according to any one of claims 1 to 9, wherein the pneumatic tire for a construction vehicle is mounted so that the lug groove is grounded from an end portion on a tire equator side during traveling.