JPH03132403A - Radial tire for heavy load - Google Patents

Radial tire for heavy load

Info

Publication number
JPH03132403A
JPH03132403A JP1269205A JP26920589A JPH03132403A JP H03132403 A JPH03132403 A JP H03132403A JP 1269205 A JP1269205 A JP 1269205A JP 26920589 A JP26920589 A JP 26920589A JP H03132403 A JPH03132403 A JP H03132403A
Authority
JP
Japan
Prior art keywords
tire
side wall
grooves
angle
wall portion
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
JP1269205A
Other languages
Japanese (ja)
Inventor
Tetsuto Tsukagoshi
哲人 塚越
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Bridgestone Corp
Original Assignee
Bridgestone Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Bridgestone Corp filed Critical Bridgestone Corp
Priority to JP1269205A priority Critical patent/JPH03132403A/en
Publication of JPH03132403A publication Critical patent/JPH03132403A/en
Pending legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/04—Tread patterns in which the raised area of the pattern consists only of continuous circumferential ribs, e.g. zig-zag
    • B60C11/042—Tread patterns in which the raised area of the pattern consists only of continuous circumferential ribs, e.g. zig-zag further characterised by the groove cross-section
    • B60C11/047—Tread patterns in which the raised area of the pattern consists only of continuous circumferential ribs, e.g. zig-zag further characterised by the groove cross-section the groove bottom comprising stone trapping protection elements, e.g. ribs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/13—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • B60C11/1307—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/13—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • B60C11/1307—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls
    • B60C2011/133—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls comprising recesses
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/13—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • B60C11/1307—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls
    • B60C2011/1338—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove walls comprising protrusions
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B60—VEHICLES IN GENERAL
    • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00—Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03—Tread patterns
    • B60C11/13—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • B60C11/1353—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove bottom
    • B60C2011/1361—Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping with special features of the groove bottom with protrusions extending from the groove bottom

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Tires In General (AREA)

Abstract

PURPOSE:To improve abrasion resisting and stone bite resisting properties by specifying each wall angle of an upper side wall part, an intermediate side wall part and a lower side wall part of a groove to a tire equatorial surface in a plurality of grooves which define a number of land parts formed on a tire tread part. CONSTITUTION:In a radial tire 1 for heavy load, wide lug grooves 16a and narrow lug grooves 16b extending to a shoulder part 4 from the vicinities of both end parts of a tread part 12 are formed. A plurarity of grooves 18 are formed zigzag in the tread part 12 crossing obliquely to the tire equatorial surface and a plurarity of block rows 20, 22 are defined by the grooves 18. In this case, the grooves 18 are formed so as to open outward in the diametric direction of the tire. To the tire equatorial surface, wall angle alpha of an upper side wall part 24 is set with angle range of 0 deg.<=alpha<=20 deg., wall angle beta of an intermediate side wall part 26 with 15 deg.<=beta<=90 deg., and wall angle gamma of a lower side wall part 30 with 30 deg.<=gamma<=15 deg. respectively.

Description

【発明の詳細な説明】 （産業上の利用分野） この発明は、耐偏摩耗特性及び耐石噛み特性に優れた重
荷重用ラジアルタイヤに関するものである。DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a heavy-duty radial tire with excellent uneven wear resistance and rock-biting resistance.

（従来の技術） タイヤトレッド部に形成された溝により、タイヤ周方向
に間隔をおいて画成された複数のブロックからなるブロ
ック列を有する重荷重用ラジアルタイヤは、駆動及び制
動性能に優れ、また、排水性も良好であることから、高
速道路網の整備、拡張に伴って高速走行する機会の増大
したバス、トラック等に適用されつつある。(Prior Art) A radial tire for heavy loads, which has a block row consisting of a plurality of blocks defined at intervals in the tire circumferential direction by grooves formed in the tire tread, has excellent driving and braking performance, and Because they have good drainage properties, they are being applied to buses, trucks, etc., which have increased opportunities to travel at high speeds due to the development and expansion of expressway networks.

ところで、タイヤトレッド部にブロック列を画成するそ
れら溝は、通例、■字状の断面形状をしており、その形
状ゆえに、トラック、バス等の重荷重用車両にあっては
、それら溝に石を噛みにくいと言う利点を有している。Incidentally, the grooves that define the block rows in the tire tread usually have a letter-shaped cross-section, and because of this shape, in heavy-duty vehicles such as trucks and buses, stones are not placed in these grooves. It has the advantage of being difficult to chew.

（発明が解決しようとする課題） しかしながら、■字状の断面形状をした溝により画成さ
れるそれぞれのブロックは、その形状ゆえにブロックの
剛性を高く設定することができるものの、ブロックの周
縁部、とくにはその張出部分がタイヤ転勤に伴って路面
に引きすられ易く、局所的な摩耗が発生する一因ともな
る。(Problem to be Solved by the Invention) However, although each block defined by grooves having a cross-sectional shape of a letter ``■'' can have high rigidity due to its shape, the peripheral edge of the block In particular, the overhanging portion is likely to be dragged along the road surface as the tires shift, and this becomes a cause of localized wear.

この局所的な摩耗は、タイヤ転勤に伴う走行距離の増大
に伴って漸次進展し、各ブロックの周縁部の機能に依存
したタイヤ性能、とくには、駆動及び制動性能に悪影響
を及ばずはかりでなく、タイヤ寿命をも大幅に低下させ
ることとなる。This localized wear gradually progresses as the mileage increases due to tire transfer, and the tire performance that depends on the function of the peripheral edge of each block, especially the driving and braking performance, is not adversely affected. , it will also significantly reduce tire life.

このため、ブロック、とくにはその周縁部の剛性を低下
させるべく、ブロックを画成ずろ溝の断面をＵ字形状と
したタイヤもある。For this reason, in order to reduce the rigidity of the block, especially the peripheral edge thereof, there are some tires in which the gutter grooves defining the block have a U-shaped cross section.

しかしながら、そのようなタイヤにあっては、そきＵ字
断面形状をした溝に石を挟み込み易く、また、挟み込ま
れた石が溝側壁部分で弾性的に挟持されるので、石を排
出しにくいと言う欠点があり、更には、そのような状態
で走行すると、タイヤ転勤に伴って溝底部に負荷が繰り
返し作用する結果、当該部分が損傷を受け、最悪の場合
にはタイヤ破損に到ることともなる。However, in such tires, stones tend to get caught in the grooves that have a U-shaped cross-section, and the stones are held elastically by the side walls of the grooves, making it difficult to eject the stones. Furthermore, if you drive in such conditions, the load will be applied repeatedly to the bottom of the groove as the tires shift, resulting in damage to that part and, in the worst case, the tire will break. It also becomes.

このことは、実質的にタイヤ周方向に溝を延在させた、
いわゆるリブパターンを有するタイヤにあっても同様で
ある。This means that the grooves substantially extend in the circumferential direction of the tire.
The same applies to tires having a so-called rib pattern.

本発明は、このような問題に鑑みてなされたものであり
、従来のタイヤ構造にあっては互いに相反する耐偏摩耗
及び耐石噛み特性の両特性を同時に満足する重荷重用ラ
ジアルタイＡ・を提供することをその目的とする。The present invention was made in view of these problems, and provides a heavy-duty radial tie A. Its purpose is to provide.

（課題を達成するための手段） この目的を達成するため、本発明は、タイヤトレッド部
に形成された複数の溝と、それら溝によって隔てられた
陸部とを有する重荷重用ラジアルタイヤにおいて、当該
溝は、タイヤ径方向外方に拡開してトレッド表面に開口
する上部側壁部分と、上部側壁部分に隣接してタイヤ径
方向外方に拡開する中部側壁部分と、中部側壁部分に隣
接してタイヤ径方向外方に拡開するとともに、溝底部を
形成する下部側壁部分と、タイヤ周方向に所定距離離間
して中部側壁部分に形成された細溝とを具え、タイヤ赤
道面に対し、それぞれ上部側壁部分のなす角度αを０≦
α≦２０°、中部側壁部分のなす角度（β）を１５≦β
≦９０°、そして下部側壁部分のなす角度Ｔを０≦Ｔ≦
１５°の角度範囲内の値とする。(Means for Achieving the Object) In order to achieve this object, the present invention provides a heavy-duty radial tire having a plurality of grooves formed in a tire tread portion and a land portion separated by the grooves. The groove includes an upper sidewall portion that expands outward in the tire radial direction and opens onto the tread surface, a middle sidewall portion that expands outward in the tire radial direction adjacent to the upper sidewall portion, and a groove that is adjacent to the middle sidewall portion. The tire has a lower sidewall portion that expands outward in the tire radial direction and forms a groove bottom, and a thin groove formed in the middle sidewall portion at a predetermined distance in the circumferential direction of the tire. The angle α formed by the upper side wall portion is 0≦
α≦20°, the angle (β) formed by the middle side wall part is 15≦β
≦90°, and the angle T formed by the lower side wall portion is 0≦T≦
The value shall be within the angular range of 15°.

さて、第１図に本発明を適用した重荷重用ラジアルタイ
ヤ１０のトレッドパターンを示す。なお、簡略のため、
ここでは図示しないが、タイヤ１ｏの内部構造は、−船
釣なラジアル構造をしている。Now, FIG. 1 shows a tread pattern of a heavy-duty radial tire 10 to which the present invention is applied. For the sake of brevity,
Although not shown here, the internal structure of the tire 1o has a radial structure.

タイＡ・１０は、その１−レット部１２の両端部近情が
らショルダ一部１４にかけて、タイヤ幅方向に延在する
幅広のラグ溝１６ａと、そのラグ溝の溝幅より小さな溝
幅の幅狭のラグ溝１６ｂとが形成されており、それらラ
グ溝１６ａ、　１６ｂは、タイヤ周方向に交互に一定間
隔をおいて相互に離間する。The tie A 10 has a wide lug groove 16a extending in the tire width direction from both ends of the 1-let part 12 to the shoulder part 14, and a groove width smaller than the groove width of the lug groove. Narrow lug grooves 16b are formed, and these lug grooves 16a, 16b are alternately spaced apart from each other at regular intervals in the tire circumferential direction.

一方、トレッド部１２には複数の溝１８が、タイヤ赤道
面に対して実質的に斜交してジグザグ状に形成されてお
り、それら各溝１８の一端は、一方のショルダ一部に位
置する広幅のラグ溝にそれぞれ連通し、各溝１８の他端
は、他方のショルダ一部に形成された広幅のラグ溝にそ
れぞれ連通しており、それら複数の溝１８は、互いに交
差してタイヤ周方向にほぼ所定間隔をおいて離間する複
数のブロックからなるブロック列２０及び２２．２２を
形成する。On the other hand, a plurality of grooves 18 are formed in the tread portion 12 in a zigzag shape substantially obliquely with respect to the tire equatorial plane, and one end of each groove 18 is located in a part of one shoulder. Each groove 18 communicates with a wide lug groove, and the other end of each groove 18 communicates with a wide lug groove formed in a part of the other shoulder. Block rows 20 and 22.22 are formed of a plurality of blocks spaced apart at substantially predetermined intervals in the direction.

それら各ブロックを画成するそれぞれの溝１８を、各ブ
ロックに関連する部分でその延在方向を変化させること
により、タイヤ赤道面に対して斜めに延在するブロック
周縁部におけるエツジ成分を増加させることができる。By changing the extending direction of each groove 18 that defines each block in the portion related to each block, the edge component at the block peripheral portion extending obliquely to the tire equatorial plane is increased. be able to.

そして、各ブロックの中央部分にその長手方向に延在さ
せて形成したブロック溝２０によるエツジ成分の増加分
と相まって、タイヤ幅方向に対する運動を規制してタイ
ヤの横滑りを抑制し、操縦性、安定性を向上させるとと
に、路面上に形成された水膜を切断してタイヤと路面と
の接触を担保する、いわゆるエツジ効果をもたらし、ウ
ェット性能を向上させる。Coupled with the increase in the edge component due to the block groove 20 formed in the center of each block and extending in the longitudinal direction, the movement in the tire width direction is restricted, suppressing tire skidding, improving maneuverability and stability. In addition to improving wet performance, it also cuts through the water film that forms on the road surface, creating a so-called edge effect that ensures contact between the tire and the road surface, thereby improving wet performance.

なお、それらブロックにそれぞれ形成されたブロック溝
２０は、ブロック中央部分と周縁部分との剛性を平均化
し、全体としてのブロックの剛性をより均一なものとす
る効果もあり、偏摩耗の発生を抑制すると言う効果もあ
る。In addition, the block grooves 20 formed in each of these blocks have the effect of equalizing the rigidity of the central part and the peripheral part of the block, making the rigidity of the block as a whole more uniform, and suppressing the occurrence of uneven wear. There is also the effect of doing so.

ところで、溝１８は、第２図（ａ）に示したような断面
形状をしており、トレッド１２の表面に開口する傾斜側
壁部分よりなる上部側壁部分２４と、上部側壁部分に隣
接する中部側壁部分２６と、この中部側壁部分に隣接す
るととも、溝底部２８を形成する下部側壁部分３０と、
第２図（ｂ）に明示したように、中部側壁部分２６に形
成され、タイヤ周方向に所定間隔離間する細溝３２とを
具える。By the way, the groove 18 has a cross-sectional shape as shown in FIG. a lower sidewall portion 30 adjacent to the middle sidewall portion and forming a groove bottom 28;
As clearly shown in FIG. 2(b), narrow grooves 32 are formed in the middle side wall portion 26 and spaced apart by a predetermined distance in the circumferential direction of the tire.

それら上部側壁部分２４、中部側壁部分２６そして下部
側壁部分３０は、いずれもタイヤ径方向外方に向けて拡
開しており、タイヤ赤道面に対して上部側壁部分２４が
なず角度αを０°≦α≦２０°、好ましくはＯ°≦α≦
１０°の範囲から、中部側壁部分２６がなす角度βを１
５≦β≦９０°、好ましくは３０゜≦β≦６０°の範囲
から、そして下部側壁部分のなず角度ＴをＯ°≦Ｔ≦１
５°、好ましくは０°≦Ｔ≦１０°の角度範囲内からそ
れぞれ選択するものとする。The upper side wall portion 24, the middle side wall portion 26, and the lower side wall portion 30 all expand outward in the tire radial direction, so that the upper side wall portion 24 forms an angle α of 0 with respect to the tire equatorial plane. °≦α≦20°, preferably O°≦α≦
From the range of 10°, the angle β formed by the middle side wall portion 26 is set to 1
5≦β≦90°, preferably 30°≦β≦60°, and the angle T of the lower side wall portion is O°≦T≦1.
Each angle shall be selected from within the angle range of 5°, preferably 0°≦T≦10°.

ここで、上部側壁部分２４がタイヤ赤道面に対してなす
角度αを、０°≦α≦２０°の角度範囲内から選択する
のは、角度αを２０°より大きくすると、初期使用状態
下でブロック、とくには、その蹴り出し側部分に偏摩耗
が発生し易くなるからであり、一方、角度αを０°より
小さく、つまりタイヤ赤道面にほぼ平行又はタイヤ径方
向外方に向けて閉じた断面形状の溝側壁とすると、ブロ
ックの周縁部が欠は易く、更にはブロックそれ自身が破
断することとなるからであり、それら偏摩耗及びブロッ
クの破断を一層有利に解決するには、０°≦α≦１０°
の角度範囲内の値とすることが好ましい。Here, the angle α that the upper side wall portion 24 makes with respect to the tire equatorial plane is selected from within the angle range of 0°≦α≦20°.If the angle α is larger than 20°, the This is because uneven wear tends to occur on the block, especially on the kicking side part.On the other hand, when the angle α is smaller than 0°, that is, when the block is closed almost parallel to the tire equatorial plane or toward the outside in the tire radial direction, This is because if the groove side walls have a cross-sectional shape, the peripheral edge of the block is likely to chip and the block itself will break. ≦α≦10°
It is preferable to set the value within the angular range of .

一方、中部側壁部分がタイヤ赤道面に対してなす角度β
を、１５°≦β≦９０°、好ましくは３０°≦β≦６０
°の角度範囲内から選択するのは、角度βが９０°より
大きくなると、中部側壁部分２６が、溝１８の内方に突
出する階段状又はタイヤ径方向外方に向けて突出する形
状をとるので、走行距離の増加に伴うトレッドの摩耗の
進展につれて、その階段状部分又は突出部分の存在に起
因するブロック剛性の高さ故に、ブロック周縁部に偏摩
耗を生じ易いからである。更には、突出形状とした場合
には、当該突出部分間に石を挾み込み易くなるからであ
る。On the other hand, the angle β that the middle side wall portion makes with the tire equatorial plane
15°≦β≦90°, preferably 30°≦β≦60
When the angle β is greater than 90°, the middle side wall portion 26 takes a step-like shape that projects inward of the groove 18 or projects outward in the tire radial direction. Therefore, as the tread wear progresses as the mileage increases, uneven wear tends to occur at the block periphery due to the high block rigidity caused by the presence of the stepped portion or protruding portion. Furthermore, in the case of a protruding shape, it becomes easier to insert stones between the protruding parts.

これに対し、角度βを１５°より小さく設定すると、所
望の石噛み防止性能を期待できなくなるからである。On the other hand, if the angle β is set smaller than 15°, the desired stone-causing prevention performance cannot be expected.

そして、中部側壁部分２６に形成した細溝３２のタイヤ
周方向における間隔ｄ及びその溝深さｈは、第２図（ｂ
）及び（Ｃ）に示したように、ｄ　〜１．５〜６　ｍｍ
、好ましくは２〜４　ｍｍとすると共に、ｈ＝１〜６　
ｍｍの範囲内から選択するものとする。The interval d in the tire circumferential direction of the narrow grooves 32 formed in the middle side wall portion 26 and the groove depth h thereof are shown in FIG.
) and (C), d ~1.5-6 mm
, preferably 2 to 4 mm, and h=1 to 6
It shall be selected from within the range of mm.

このことにより、トレッドの摩耗の進展に際しても、タ
イヤ赤道面に対して中部側壁部分がなす角度βを、上部
側壁部分のなす角度αより大きく設定した場合にあって
も、中部側壁部分における剛性を上部側壁部分のそれに
ほぼ等しくすることができ、耐石噛み特性を維持しつつ
、偏摩耗の発生を抑制することができるからである。As a result, as tread wear progresses, even if the angle β formed by the middle sidewall with respect to the tire equatorial plane is set larger than the angle α formed by the upper sidewall, the rigidity of the middle sidewall can be reduced. This is because it can be made almost equal to that of the upper side wall portion, and the occurrence of uneven wear can be suppressed while maintaining the stone bite resistance property.

また、下部側壁部分３０がタイヤ赤道面に対してなす角
度Ｔを、０°≦Ｔ≦１５°、好ましくは０゜≦Ｔ≦１０
°の角度範囲内から選択するのは、角度γを１５°より
大きくすると、トレッド部１２の摩耗が進展した状態下
での、下部側壁部分３０の周縁部によるエツジ効果を期
待することができず、ウェット性能が低下するからであ
り、０°より小さくすると、ブロックが底部がタイヤ径
方向内方にむけて拡開した形状をとるため、ブロックが
破損し易いからである。Further, the angle T that the lower side wall portion 30 makes with respect to the tire equatorial plane is set to 0°≦T≦15°, preferably 0°≦T≦10°.
The reason why the angle γ is selected from within the range of 15° is because if the angle γ is larger than 15°, an edge effect due to the peripheral edge of the lower side wall portion 30 cannot be expected under conditions where the tread portion 12 has progressed to wear. This is because the wet performance deteriorates, and when the angle is smaller than 0°, the block takes a shape in which the bottom part expands inward in the tire radial direction, and the block is likely to be damaged.

そして、第１図に示す実施例にあっては、溝１８の溝底
部に沿って、複数の石噛み防止突条３４を相互に離間さ
せて配設し、トレッド表面の摩耗が進展した状態下にあ
っても、下部側壁部分３０に石が挟み込まれるのを防止
する構成とした。この石噛み防止突条３４の溝底部から
の高さは、溝１８の溝深さに対して１５％〜５０％の範
囲内から選択することが好ましく、例えば、第１回の線
Ｃ−Ｃに沿う断面を示す第３図に示したように、トレッ
ド表面１２における溝１８の溝幅を１６．９ｍｍ、その
溝深さを２７ｍｍとした場合には、突条の高さを４　ｍ
ｍとした。In the embodiment shown in FIG. 1, a plurality of stone-biting prevention protrusions 34 are arranged at a distance from each other along the bottom of the groove 18, so that the tread surface can be prevented from being worn even when the tread surface is worn. The structure is such that stones are prevented from being caught in the lower side wall portion 30 even when the stone is in the lower side wall portion 30. It is preferable that the height of the stone bite prevention protrusion 34 from the groove bottom is selected within the range of 15% to 50% of the groove depth of the groove 18, for example, the height of the first line C-C. As shown in FIG. 3, which shows a cross section along
It was set as m.

石噛み防止突条の高さをこのような範囲内の値０ とすることにより、トレッド表面の摩耗が進展した状態
下にあっても、謝方噛み性能を充分に担保することがで
き、従来の石噛み防止突条のような比較的高さのあるも
のに比べ、石噛み防止の点てより有利となる。By setting the height of the stone bite prevention protrusion to a value of 0 within this range, even when the tread surface is in a state where wear has progressed, it is possible to sufficiently ensure the gravel bite performance, which is better than the conventional tread surface. It is more advantageous in terms of preventing stone entrapment compared to relatively tall ones such as stone entrapment prevention protrusions.

（作　用） このようなタイヤにあっては、タイヤ赤道面に対して、
溝の上部側壁部分のなす角度αを０≦α≦２０°　中部
側壁部分のなす角度（β）を１５≦β≦９０°、そして
下部側壁部分のなず角度ＴをＯ≦Ｔ≦１５°の角度範囲
内から選択するごとにより、タイヤの初期使用状態にあ
っても、それら溝により画成されたブロックの周縁部に
おける剛性を適当なものとすることができ、タイヤ転勤
に伴う踏み込み、蹴り出しに起因する偏摩耗を有効に防
止することができ、更には、−Ｆ部側壁面に協働する中
部側壁面により、石噛みを有効に防止することができる
。(Function) In such a tire, with respect to the tire equatorial plane,
The angle α formed by the upper side wall portion of the groove is 0≦α≦20°, the angle (β) formed by the middle side wall portion is 15≦β≦90°, and the angle T of the lower side wall portion is O≦T≦15°. By selecting each angle within the range, even in the initial use state of the tire, the rigidity at the peripheral edge of the block defined by these grooves can be set to an appropriate value, and the rigidity of the block defined by the grooves can be adjusted to an appropriate value. Uneven wear caused by this can be effectively prevented, and furthermore, the middle side wall surface that cooperates with the side wall surface of the -F section can effectively prevent stone bite.

そして、タイヤ表面の摩耗が進展した状態にあっては、
中部側壁部分に形成した細溝が、ブロックの剛性を変化
させることなく一様に保持するので、引き続いて耐偏摩
耗性能及び謝方噛み性能を維持するごとができ、使用後
期にあっても、下部側壁部分のエツジ効果により、充分
なウエッ１〜性能が担保されるので、タイヤ寿命を延長
するごとができる。When the tire surface wear has progressed,
The narrow grooves formed in the middle side wall part maintain the rigidity of the block uniformly without changing it, so it is possible to continue to maintain uneven wear resistance performance and vertical bite performance, even in the later stages of use. The edge effect of the lower sidewall portion ensures sufficient wedging performance, thereby extending the life of the tire.

（実施例） 第１図に示すトレッドパターンを有するザイス１１、Ｏ
ＯＲ２２，５のタイヤを用い、その溝の横断面形状を種
々変更して耐偏摩耗特性及び謝方噛み特性について比較
試験を行った。(Example) Zice 11, O having the tread pattern shown in FIG.
Using tires with an OR of 22.5 and varying the cross-sectional shape of the grooves, comparative tests were conducted on uneven wear resistance and lateral chewing characteristics.

なお、トレッド表面におジノる溝の溝幅をし、中部側壁
部分と下部側壁部分との接続部分における溝幅を１、タ
イヤ赤道面に対して上部側壁部分のなす角度をα、中部
側壁部分のなす角度をβ、下部側壁部分のなす角度をγ
とし、中部側壁部分に形成された細溝のタイヤ周方向に
おける間隔をｄそして、細溝の溝深さをｈとする。In addition, the groove width of the groove on the tread surface is 1, the groove width at the connection part between the middle side wall part and the lower side wall part is 1, the angle made by the upper side wall part with respect to the tire equatorial plane is α, and the middle side wall part The angle formed by the lower side wall is β, and the angle formed by the lower side wall is γ
Let d be the interval in the circumferential direction of the tire between the narrow grooves formed in the middle side wall portion, and h be the groove depth of the narrow grooves.

◎供試タイヤ： ・実施例１：第４図（ａ）に示す横断面形状の溝を有１ ２ するタイヤで、 Ｌ＝１７ｍｍ、Ｉ＝９＋ｎｍ、α−０°、β−４５°、
Ｔ−１０°、ｄ　＝３．５　ｍｍ、　ｈ＝３ｍｍとした
もの。◎Test tire: - Example 1: A tire with grooves having the cross-sectional shape shown in FIG. 4(a), L=17 mm, I=9+nm, α-0°, β-45°,
T-10°, d = 3.5 mm, h = 3 mm.

・実施例２：第４図（ｂ）に示す横断面形状の溝を有す
るタイヤで、 Ｌ−１６，５ｍｍ、ｌ＝８ｍｍ、ｃｘ　＝１２６β−９
０°、Ｔ−１０°、ｄ　＝２　ｍｍ、　　ｈ−４ｍｍと
したもの。・Example 2: Tire with grooves having the cross-sectional shape shown in FIG. 4(b), L-16.5 mm, l=8 mm, cx=126β-9
0°, T-10°, d = 2 mm, h-4 mm.

・実施例３．第４図（Ｃ）に示す横断面形状の溝を有す
るタイヤで、 Ｉ、１８ｍｍ、　　ｌ　＝９．５　ｍｍ、　α＝４゜β
−２５°、ｒ−０°、ｄ＝５　ｍｍ、　ｈ−３ｍｍとし
たもの。・Example 3. For a tire with grooves having the cross-sectional shape shown in Fig. 4(C), I, 18 mm, l = 9.5 mm, α = 4° β
-25°, r-0°, d=5 mm, h-3 mm.

・比較例１：■字状の横断面形状の溝を有するタイヤ。Comparative Example 1: Tire with grooves having a cross-sectional shape of a letter ■.

比較例２：Ｕ字状の横断面形状の溝を有するタイヤ。Comparative Example 2: Tire with grooves having a U-shaped cross section.

◎試験方法： それぞれのタイヤを実車に装着してＪＩＳ規格に基づく
内圧及び荷重条件下で、走行試験を行った。◎Test method: Each tire was mounted on an actual vehicle and a running test was conducted under internal pressure and load conditions based on JIS standards.

・耐偏摩耗特性： ６万りまで走行させ、所定走行距離における偏摩耗の幅
を測定した。- Resistance to uneven wear: The vehicle was run up to 60,000 miles, and the width of uneven wear over a given mileage was measured.

・石噛み特性： ３万す走行後の石噛み数を調べた。・Stone bite characteristics: We investigated the number of stone bites after driving 30,000 feet.

上記試験の結果を、第５図及び次表にそれぞれ示す。The results of the above tests are shown in FIG. 5 and the following table, respectively.

表 上記表及び第５図から明らかなように、この発明に従う
タイヤは、従来のタイヤに比して耐偏摩耗性及び謝方噛
み性を両立させ得ることが分かる。As is clear from the above table and FIG. 5, it can be seen that the tire according to the present invention is able to achieve both uneven wear resistance and corner bite resistance compared to conventional tires.

なお、本発明はこれら実施例に限定されるもので３ ４ はなく、例えば、リブパターンを有するタイヤにも適用
し得るものであり、特許請求の範囲内で種々の変更が可
能である。It should be noted that the present invention is not limited to these embodiments, and can be applied to tires having a rib pattern, for example, and various modifications can be made within the scope of the claims.

（発明の効果） かくしてこの発明によれば、従来のタイヤにあっては相
反する性能である耐偏摩耗特性及び謝方噛み特性を両立
させることができ、タイヤ寿命を大幅に延長さ一ロるこ
とができる。(Effects of the Invention) Thus, according to the present invention, it is possible to achieve both uneven wear resistance and uneven wear resistance, which are contradictory properties in conventional tires, and the life of the tire is greatly extended. be able to.

【図面の簡単な説明】[Brief explanation of the drawing]

第１回は、本発明タイヤの１−レッドパターンを示す図
、 第２図（ａ）は、第１同に示すタイヤの溝の横断面形状
を示す図、 第２図（ｂ）及び（Ｃ）は、第２図（ａ）の溝を示す斜
視図及びその細溝を示す説明図、 第３図は、本発明に係る他の溝の横断面を示す図、 第４図（ａ）〜（Ｃ）は、本発明に係る別な実施例の溝
を模式的に示す説明図、そして 第５図は、本発明に係るタイヤと従来のタイヤとの耐偏
摩耗特性を示す図である。 １０−　タイヤ　　　　　　１２−トレッド部１４−　
　ショルダ一部　　　１６ａ、　１６ｂ　−ラグ溝１８
−溝　　　　　　　　　２０−　ブロック溝２４−上部
側壁部分　　　２６−中部側壁部分２８−溝底部　　　
　　　３０−下部側壁部分３２−細溝　　　　　　　３
４−石噛み防止突条第２図 （ａ） （Ｃ） 第３図 第４ 図The first part is a diagram showing the 1-red pattern of the tire of the present invention, Figure 2 (a) is a diagram showing the cross-sectional shape of the groove of the tire shown in the first part, and Figures 2 (b) and (C ) is a perspective view showing the groove in FIG. 2(a) and an explanatory view showing its narrow groove; FIG. 3 is a view showing a cross section of another groove according to the present invention; FIGS. 4(a) to 4). (C) is an explanatory diagram schematically showing the grooves of another embodiment according to the present invention, and FIG. 5 is a diagram showing uneven wear resistance characteristics of the tire according to the present invention and a conventional tire. 10- Tire 12- Tread portion 14-
Shoulder part 16a, 16b - Lug groove 18
-Groove 20-Block groove 24-Upper side wall portion 26-Middle side wall portion 28-Groove bottom
30-Lower side wall portion 32-Slot 3
4- Stone-bite prevention ridges Fig. 2 (a) (C) Fig. 3 Fig. 4

Claims (1)

【特許請求の範囲】 １、タイヤトレッド部に形成された複数の溝と、それら
溝によって隔てられた陸部とを有する重荷重用ラジアル
タイヤにおいて、 前記溝は、タイヤ径方向外方に拡開してトレッド表面に
開口する上部側壁部分と、上部側壁部分に隣接してタイ
ヤ径方向外方に拡開する中部側壁部分と、中部側壁部分
に隣接してタイヤ径方向外方に拡開するとともに、溝底
部を形成する下部側壁部分と、タイヤ周方向に所定距離
離間して中部側壁部分に形成された複数の細溝とを具え
、 タイヤ赤道面に対し、それぞれ上部側壁部分のなす角度
αを０≦α≦２０°、中部側壁部分のなす角度（β）を
１５≦β≦９０°、そして下部側壁部分のなす角度γを
０≦Ｔ≦１５°の角度範囲内の値としたことを特徴とす
る重荷重用ラジアルタイヤ。[Claims] 1. A heavy-duty radial tire having a plurality of grooves formed in a tire tread portion and a land portion separated by the grooves, wherein the grooves expand outward in the tire radial direction. an upper sidewall portion that opens onto the tread surface; a middle sidewall portion that expands outward in the tire radial direction adjacent to the upper sidewall portion; and a middle sidewall portion that expands outward in the tire radial direction adjacent to the middle sidewall portion; It comprises a lower side wall portion forming a groove bottom and a plurality of narrow grooves formed in the middle side wall portion at a predetermined distance in the tire circumferential direction, and the angle α of each upper side wall portion with respect to the tire equatorial plane is 0. ≦α≦20°, the angle (β) formed by the middle side wall portion is 15≦β≦90°, and the angle γ formed by the lower side wall portion is a value within the angle range of 0≦T≦15°. A radial tire for heavy loads.
JP1269205A 1989-10-18 1989-10-18 Radial tire for heavy load Pending JPH03132403A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP1269205A JPH03132403A (en) 1989-10-18 1989-10-18 Radial tire for heavy load

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP1269205A JPH03132403A (en) 1989-10-18 1989-10-18 Radial tire for heavy load

Publications (1)

Publication Number Publication Date
JPH03132403A true JPH03132403A (en) 1991-06-05

Family

ID=17469137

Family Applications (1)

Application Number Title Priority Date Filing Date
JP1269205A Pending JPH03132403A (en) 1989-10-18 1989-10-18 Radial tire for heavy load

Country Status (1)

Country Link
JP (1) JPH03132403A (en)

Cited By (19)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5417269A (en) * 1992-12-22 1995-05-23 Sumitomo Rubber Industries, Ltd. Pneumatic tire for heavy vehicle
JPH10211805A (en) * 1997-01-28 1998-08-11 Pirelli Coordinamento Pneumatici Spa Tire and tread band thereof
US5975172A (en) * 1996-10-01 1999-11-02 Sumitomo Rubber Industries, Ltd. Pneumatic tire
US6000451A (en) * 1996-07-19 1999-12-14 Sumitomo Rubber Industries, Ltd. Pneumatic tire including at least one projection
US6176284B1 (en) * 1996-07-19 2001-01-23 Sumitomo Rubber Industries, Ltd. Pneumatic tire
JP2001253211A (en) * 2000-01-07 2001-09-18 Bridgestone Corp Pneumatic radial tire
JP2001354011A (en) * 2000-06-14 2001-12-25 Bridgestone Corp Pneumatic tire
JP2002029224A (en) * 2000-07-18 2002-01-29 Bridgestone Corp Pneumatic tire
JP2003054220A (en) * 2001-08-20 2003-02-26 Toyo Tire & Rubber Co Ltd Pneumatic tire
US6571843B2 (en) * 1999-12-24 2003-06-03 Sumitomo Rubber Industries, Ltd. Pneumatic tire including blocks with V-shaped corners
US6601624B2 (en) * 2001-07-11 2003-08-05 The Goodyear Tire & Rubber Company Tread groove noise diffusers
JP2006111218A (en) * 2004-10-18 2006-04-27 Yokohama Rubber Co Ltd:The Pneumatic tire
WO2006070765A1 (en) * 2004-12-27 2006-07-06 The Yokohama Rubber Co., Ltd. Pneumatic tire
EP1872974A2 (en) * 2006-07-01 2008-01-02 Continental Aktiengesellschaft Vehicle tyre with a profiled tread
EP2626221A1 (en) * 2010-10-05 2013-08-14 Bridgestone Corporation Tire
US20130263988A1 (en) * 2010-12-23 2013-10-10 Claudio Minoli Tyre for heavy load vehicle wheels
WO2019049765A1 (en) * 2017-09-06 2019-03-14 横浜ゴム株式会社 Pneumatic tire
US20200361246A1 (en) * 2018-01-23 2020-11-19 The Yokohama Rubber Co., Ltd. Pneumatic Tire
US20210188010A1 (en) * 2019-12-18 2021-06-24 The Goodyear Tire & Rubber Company Tire with tread elements including dual angled chamfer

Cited By (33)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5417269A (en) * 1992-12-22 1995-05-23 Sumitomo Rubber Industries, Ltd. Pneumatic tire for heavy vehicle
US6000451A (en) * 1996-07-19 1999-12-14 Sumitomo Rubber Industries, Ltd. Pneumatic tire including at least one projection
US6176284B1 (en) * 1996-07-19 2001-01-23 Sumitomo Rubber Industries, Ltd. Pneumatic tire
US5975172A (en) * 1996-10-01 1999-11-02 Sumitomo Rubber Industries, Ltd. Pneumatic tire
JPH10211805A (en) * 1997-01-28 1998-08-11 Pirelli Coordinamento Pneumatici Spa Tire and tread band thereof
US6571843B2 (en) * 1999-12-24 2003-06-03 Sumitomo Rubber Industries, Ltd. Pneumatic tire including blocks with V-shaped corners
JP2001253211A (en) * 2000-01-07 2001-09-18 Bridgestone Corp Pneumatic radial tire
JP2001354011A (en) * 2000-06-14 2001-12-25 Bridgestone Corp Pneumatic tire
JP4518641B2 (en) * 2000-07-18 2010-08-04 株式会社ブリヂストン Pneumatic tire
JP2002029224A (en) * 2000-07-18 2002-01-29 Bridgestone Corp Pneumatic tire
US6601624B2 (en) * 2001-07-11 2003-08-05 The Goodyear Tire & Rubber Company Tread groove noise diffusers
JP2003054220A (en) * 2001-08-20 2003-02-26 Toyo Tire & Rubber Co Ltd Pneumatic tire
JP4683600B2 (en) * 2001-08-20 2011-05-18 東洋ゴム工業株式会社 Pneumatic tire
JP2006111218A (en) * 2004-10-18 2006-04-27 Yokohama Rubber Co Ltd:The Pneumatic tire
JP4586486B2 (en) * 2004-10-18 2010-11-24 横浜ゴム株式会社 Pneumatic tire
WO2006070765A1 (en) * 2004-12-27 2006-07-06 The Yokohama Rubber Co., Ltd. Pneumatic tire
JPWO2006070765A1 (en) * 2004-12-27 2008-06-12 横浜ゴム株式会社 Pneumatic tire
JP4591446B2 (en) * 2004-12-27 2010-12-01 横浜ゴム株式会社 Pneumatic tire
EP1872974A2 (en) * 2006-07-01 2008-01-02 Continental Aktiengesellschaft Vehicle tyre with a profiled tread
EP1872974A3 (en) * 2006-07-01 2009-03-18 Continental Aktiengesellschaft Vehicle tyre with a profiled tread
EP2626221A4 (en) * 2010-10-05 2014-09-17 Bridgestone Corp Tire
EP2626221A1 (en) * 2010-10-05 2013-08-14 Bridgestone Corporation Tire
US9120353B2 (en) 2010-10-05 2015-09-01 Bridgestone Corporation Tire
US20130263988A1 (en) * 2010-12-23 2013-10-10 Claudio Minoli Tyre for heavy load vehicle wheels
US9914329B2 (en) * 2010-12-23 2018-03-13 Pirelli Tyre S.P.A. Tyre for heavy load vehicle wheels
WO2019049765A1 (en) * 2017-09-06 2019-03-14 横浜ゴム株式会社 Pneumatic tire
JPWO2019049765A1 (en) * 2017-09-06 2019-11-07 横浜ゴム株式会社 Pneumatic tire
US11407257B2 (en) 2017-09-06 2022-08-09 The Yokohama Rubber Co., Ltd. Pneumatic tire
US11897291B2 (en) 2017-09-06 2024-02-13 The Yokohama Rubber Co., Ltd. Pneumatic tire
US20200361246A1 (en) * 2018-01-23 2020-11-19 The Yokohama Rubber Co., Ltd. Pneumatic Tire
US11718130B2 (en) * 2018-01-23 2023-08-08 The Yokohama Rubber Co., Ltd. Pneumatic tire
US20210188010A1 (en) * 2019-12-18 2021-06-24 The Goodyear Tire & Rubber Company Tire with tread elements including dual angled chamfer
US11472232B2 (en) * 2019-12-18 2022-10-18 The Goodyear Tire & Rubber Company Tire with tread elements including dual angled chamfer

Similar Documents

Publication Publication Date Title
JPH03132403A (en) Radial tire for heavy load
US9079460B2 (en) Pneumatic tire
EP0342908B1 (en) Pneumatic tyre
US6481480B1 (en) Convertible tread for a radial truck or trailer tire
JP2505178B2 (en) Pneumatic radial tires for heavy loads
KR20100075969A (en) Pneumatic tire
JP4392944B2 (en) Land structure of pneumatic tires
US8881779B2 (en) Pneumatic tire with tread having dent parts and sipes
JPS61102301A (en) Pneumatic type with superior uneven-wear resistant characteristics
JPH02216304A (en) Tire for snow/ice covered road
US11207923B2 (en) Pneumatic tire
JP2017196974A (en) Pneumatic tire
JP4475756B2 (en) Pneumatic tire
CA2018565A1 (en) Heavy duty pneumatic tire
JP3204741B2 (en) Tire tread structure
JPH05278414A (en) Pneumatic tire
JP4408325B2 (en) Pneumatic tire
JP3113388B2 (en) Pneumatic tire
JP2002192917A (en) Pneumatic tire
JPH11321234A (en) Pneumatic tire
JPH0392402A (en) Pneumatic tire
JPH04143105A (en) Pneumatic radial tire
JP5698622B2 (en) tire
JPH06171321A (en) Pneumatic tire
KR100749399B1 (en) Heavy duty pneumatic radial tire