JPS63125410A - Tire for snowy and icy road - Google Patents

Tire for snowy and icy road

Info

Publication number
JPS63125410A
JPS63125410A JP61267673A JP26767386A JPS63125410A JP S63125410 A JPS63125410 A JP S63125410A JP 61267673 A JP61267673 A JP 61267673A JP 26767386 A JP26767386 A JP 26767386A JP S63125410 A JPS63125410 A JP S63125410A
Authority
JP
Japan
Prior art keywords
tire
depth
grooves
block
main
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
JP61267673A
Other languages
Japanese (ja)
Inventor
Michihiro Sugata
姿 通博
Susumu Watanabe
晋 渡辺
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.)
Yokohama Rubber Co Ltd
Original Assignee
Yokohama Rubber Co Ltd
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 Yokohama Rubber Co Ltd filed Critical Yokohama Rubber Co Ltd
Priority to JP61267673A priority Critical patent/JPS63125410A/en
Publication of JPS63125410A publication Critical patent/JPS63125410A/en
Pending legal-status Critical Current

Links

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60CVEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03Tread patterns
    • B60C11/13Tread patterns characterised by the groove cross-section, e.g. for buttressing or preventing stone-trapping
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60CVEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03Tread patterns
    • B60C11/12Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes
    • B60C11/1259Depth of the sipe
    • B60C11/1263Depth of the sipe different within the same sipe

Abstract

PURPOSE:To prevent deterioration of dry property by constituting a tread part by the rubber whose 100% modulus at -20 deg.C is less than a specific value, and by forming a calf on the block as well as by forming the tread surface with a block basic pattern. CONSTITUTION:On a tread surface of a tire for the snowy and icy road, a plurality of main grooves 1... extended in the tire circumferential direction and auxiliary grooves 2... extended in the tire axis direction are formed, a main groove 2 on the outermost side and the outside of the shoulder part are communicated with each other, and a large number of blocks 3... surrounded by these main grooves 1 and the auxiliary grooves 2 are formed. In each of the block 3, calves 4 made of narrow cut grooves respectively are formed communicating their end part with the main grooves. And a tread rubber with the 100% modulus at -20 deg.C is less than 32kg/cm<2> is used. Also, the ratio of the depth d of the auxiliary grooves 2 to the main grooves depth D is made 1.0>d/D>0.4, and the ratio of the average depth dav of the auxiliary grooves 2 to the main grooves depth D is made 0.8>dav>0.4.

Description

【発明の詳細な説明】 〔発明の技術分野〕 本発明は雪氷路走行用のタイヤに関するものである。[Detailed description of the invention] [Technical field of invention] The present invention relates to tires for driving on snowy and icy roads.

〔従来技術〕[Prior art]

一般に雪氷路用タイヤは、トレッドゴムとして一20℃
における100%モジュラスの低いものが使用され、ま
たトレッドパターンにはブロック基調のパターンが採用
され、かつそのブロックに断面方向のカーフが設けられ
るようになっている。そして、雪氷路面での運動性能(
以下、スノー性能という)は、上記−20”cでの10
0%モジュラスが低ければ低いほど、またカーフが多け
れば多いほど良好になるという特長のあることが知られ
ている。
Generally, tires for snowy and icy roads have a temperature of -20℃ as tread rubber.
A tire with a low 100% modulus is used, and a block-based pattern is adopted as the tread pattern, and the blocks are provided with a kerf in the cross-sectional direction. And maneuverability on snowy and icy roads (
(hereinafter referred to as snow performance) is 10 at -20"c above.
It is known that the lower the 0% modulus and the greater the kerf, the better the quality.

ところが、その反面で、トレッドゴムの一20℃での1
00%モジュラスが低いほど、またブロックに設けたカ
ーフが多いほど乾燥路面での操縦安定性等の運動性能(
以下、ドライ性能という)が低下してしまうという性質
がある。
However, on the other hand, the temperature of the tread rubber at 20°C
The lower the 00% modulus and the more kerfs provided on the block, the better the driving performance such as steering stability on dry road surfaces (
There is a property that the dry performance (hereinafter referred to as "dry performance") decreases.

〔発明の目的〕[Purpose of the invention]

本発明の目的は、上述のような従来の問題を解消し、ス
ノー性能を損なうことなく、ドライ性能を向上させるよ
うにした雪氷路用タイヤを提供することにある。
An object of the present invention is to provide a tire for snowy and icy roads that solves the conventional problems as described above and improves dry performance without impairing snow performance.

〔発明の構成〕[Structure of the invention]

上記目的を達成する本発明のタイヤは、−20℃におけ
る100%モジュラスが32kg/crA以下のゴムに
よってトレッド部を構成し、そのトレッド面にタイヤ周
方向に延びる複数の主溝と、タイヤ周方向を横切る副溝
とから溝面積比率が30〜50%であるブロック基調パ
ターンを形成し、各ブロックにはタイヤ周方向を横切り
少なくとも一端が前記主溝に連通ずるカーフを設け、ま
た前記副溝の深さdを主溝深さDに対する比率として1
.0>d/D>0.4の範囲にするとともに、該副溝の
平均深さd mVを主溝深さDに対する比率として0.
8>day/D〉0.4の範囲にしたことを特徴とする
ものである。
The tire of the present invention that achieves the above object has a tread portion made of rubber having a 100% modulus of 32 kg/crA or less at -20°C, and a plurality of main grooves extending in the circumferential direction of the tire on the tread surface, and a plurality of main grooves extending in the circumferential direction of the tire. A block basic pattern having a groove area ratio of 30 to 50% is formed from the minor grooves that cross the main groove, and each block is provided with a kerf that crosses the circumferential direction of the tire and has at least one end communicating with the main groove. The ratio of depth d to main groove depth D is 1
.. 0>d/D>0.4, and the ratio of the average depth d mV of the minor groove to the main groove depth D is 0.
8>day/D>0.4.

第1図は本発明の実施例による雪氷路用タイヤのトレッ
ド面を示すもので、1 、−、 1はタイヤ周方向に延
びる複数の主溝、2.−・、2はタイヤ周方向を横切る
方向に延びる副溝である。
FIG. 1 shows the tread surface of a tire for snowy and icy roads according to an embodiment of the present invention, in which 1, -, 1 are a plurality of main grooves extending in the circumferential direction of the tire, 2. -., 2 are sub grooves extending in a direction transverse to the tire circumferential direction.

上記副溝2は、互いに隣接する主溝1.1の間や、最外
側の主溝2とショルダ一部外側の間をそれぞれ連通し、
それによってこれら主溝1と副溝2に囲まれた多数のブ
ロック3 、−、 3を形成している。主溝1や副溝2
は、図ではわかりやすくするためハンチングを施して示
しである。
The sub-groove 2 communicates between the main grooves 1.1 adjacent to each other, and between the outermost main groove 2 and a part of the shoulder outside,
Thereby, a large number of blocks 3, -, 3 surrounded by the main groove 1 and the sub groove 2 are formed. Main groove 1 and minor groove 2
is shown with hunting in the figure for clarity.

また、各ブロック3には、それぞれ細い切込み溝からな
るカーフ4が少なくとも一つ設けられており、そのカー
フ4はその一端または両端を主溝1に対して連通させて
いる。
Further, each block 3 is provided with at least one kerf 4 consisting of a thin cut groove, and the kerf 4 communicates with the main groove 1 at one end or both ends thereof.

本発明において、上述のようなトレッドパターンを構成
するために使用されるトレッドゴムは、−20℃におけ
る100%モジュラスが32kB/crA以下であるこ
とが必要である。この−20℃での100%モジュラス
が32kg/cnlより大きい場合には、本発明の目的
とする所定のスノー性能を十分に発揮することができな
くなる。
In the present invention, the tread rubber used to construct the above-described tread pattern must have a 100% modulus of 32 kB/crA or less at -20°C. If the 100% modulus at -20°C is greater than 32 kg/cnl, it will not be possible to sufficiently exhibit the desired snow performance aimed at by the present invention.

また、トレッド面に形成するトレッドパターンとしては
、雪氷路で高いトラクションを発揮するようにするため
に、例えば上述の第1図に例示するようなブロック基調
のパターンにする必要があり、かつそのブロックにはカ
ーフを少なくとも一つ設けることが必要である。
In addition, in order to exhibit high traction on snowy and icy roads, the tread pattern formed on the tread surface needs to be a block-based pattern, for example, as illustrated in FIG. It is necessary to provide at least one kerf.

しかも、本発明では、このようなブロック基j周パター
ンにおいて、このフ゛ロック基3周パターンを形成して
いる主溝と副溝とがトレッド面に対して占める溝面積比
率を30〜50%であるようにすることが必要である。
Moreover, in the present invention, in such a block base j circumference pattern, the groove area ratio of the main grooves and minor grooves forming the block base three circumference pattern to the tread surface is 30 to 50%. It is necessary to do so.

この溝面積比率が30%よりも小さいと、フ゛ロック基
言周パターンであっても十分なスノー性能を発揮するこ
とができなくなる。また、50%を超えるほどに大きい
と、カーフが設けられていることと相俟ってブロック剛
性が小さくなりすぎ、それによってスノー性能を低下す
るとともに、特に乾燥路面を走行したときの耐摩耗性を
著しく低下するようになる。
If this groove area ratio is smaller than 30%, sufficient snow performance cannot be achieved even with a block pattern. If it exceeds 50%, the stiffness of the block becomes too small due to the presence of the kerf, which reduces snow performance and reduces wear resistance, especially when driving on dry road surfaces. becomes markedly lower.

また、ブロックに設けるカーフはタイヤ周方向を横切る
方向に設け、少なくともその一端を主溝に対して連通さ
せる必要がある。このカーフはタイヤ周方向を横切れば
よいので、必ずしも第1図に例示したようにタイヤ周方
向に直角である必要はなく、や・斜めに交差するように
したものでも差し支えない。
Further, the cuff provided on the block must be provided in a direction transverse to the circumferential direction of the tire, and at least one end thereof must be communicated with the main groove. Since this kerf only needs to cross the tire circumferential direction, it does not necessarily have to be perpendicular to the tire circumferential direction as illustrated in FIG. 1, but may also intersect somewhat diagonally.

このカーフはブロック剛性を調整する作用を行い、ブロ
ック自体をや\柔軟にすることによってトラクションを
向上させ、スノー性能を著しく向上するようにする。こ
のようなスノー性能向上のためには、カーフの少なくと
も一端を主溝に対して連通させることが重要である。
This kerf has the effect of adjusting block stiffness, making the block itself slightly more flexible, improving traction and significantly improving snow performance. In order to improve such snow performance, it is important to communicate at least one end of the kerf with the main groove.

さらに本発明において重要なことは、副溝の深さを上述
した範囲に設定することである。すなわち、第2図に例
示するように、副溝2の深さdが、その最小深さdl、
1およびd maxとも主溝の深さDに対する比率とし
て1.0dd/D>0.4の範囲にあるようにし、さら
に下記式で計算される平均深さd、vを、主溝の深さD
に対する比率として0.8>dil、/D>0.4なる
範囲にすることである。
Furthermore, what is important in the present invention is to set the depth of the sub-groove within the above-mentioned range. That is, as illustrated in FIG. 2, the depth d of the sub-groove 2 is the minimum depth dl,
1 and d max are both in the range of 1.0dd/D>0.4 as a ratio to the depth D of the main groove, and the average depths d and v calculated by the following formula are calculated as the depth of the main groove. D
The ratio should be within the range of 0.8>dil and /D>0.4.

本発明においてさらに好ましくは、上記副溝2は、第2
図に示すように深さdを、両端の主溝1.1に連通ずる
領域では浅く、中間域では深くなるように構成にすると
よい。
More preferably in the present invention, the minor groove 2 has a second
As shown in the figure, it is preferable that the depth d is shallow in the region communicating with the main grooves 1.1 at both ends and deep in the intermediate region.

副溝の深さを上述のような範囲に設定し、さらに好まし
くは深さに、特に第2図に示すような変化を与えること
によって、トレッドゴムの一20℃での100%モジュ
ラスを低くシ、かつ多数のカーフを設けたことによって
もたらされるドライ性能の低下を抑制することができる
ようになる。すなわち、従来の雪氷路用タイヤでは得ら
れなかったドライ性能の著しい向上が可能になる。
By setting the depth of the sub-grooves within the above-mentioned range, and more preferably by changing the depth, especially as shown in Figure 2, the 100% modulus of the tread rubber at 20°C can be made low. , and it becomes possible to suppress deterioration in dry performance caused by providing a large number of kerfs. That is, it becomes possible to significantly improve dry performance, which could not be achieved with conventional tires for snowy and icy roads.

〔実施例〕〔Example〕

第1図に示すようなブロック基調パターンを有し、溝面
積比率が40%であり、かつトレッドゴムとして、下記
するようなゴム組成にすることによって一20℃におけ
る100%モジュラスを30kg/cnlにしたゴムを
使用し、副溝の深さのみを後述の表のように種々に変え
た6種類のタイヤA、B、C,D、E、F (タイヤサ
イズはいずれも165/80R1382Q)を製作した
。これらタイヤのうち、CおよびEは本発明タイヤに該
当し、他のA、B、D、Fは比較タイヤである。
It has a block basic pattern as shown in Figure 1, the groove area ratio is 40%, and the tread rubber has the following rubber composition, so that the 100% modulus at -20°C is 30 kg/cnl. Six types of tires A, B, C, D, E, and F (all tire sizes are 165/80R1382Q) were manufactured using the same rubber, with only the depth of the minor grooves being varied as shown in the table below. did. Among these tires, C and E correspond to tires of the present invention, and the others A, B, D, and F are comparative tires.

トレッドゴムの組成(重量部で表示) 天然ゴム(R3S#4)      ?0.00B R
(Nipol  1441 )      41 、 
25亜鉛華             5.00ステア
リン酸           3.00老防剤(San
toflex 13)      2.  OOマイク
ロクリスタリンワックス  2.00カーボンブラツク
N339   75.00セバシン酸ジオクチルエステ
ル 28.75N−オキシジエチレン−2−ベンゾジア
ゾリルスルフェンアミド       1.10硫黄 
              2.00上記6種類のタ
イヤについて゛、1800ccのFF車を試験車とし、
それぞれ雪上走行時の操縦安定性(スノー性能)と乾燥
路面走行時の操縦安定性(ドライ性能)とを評価し、総
合点を10点法で表した結果を、次の表に示した。表中
の評価点が7点以上のものは、タイヤ性能として実用性
があるとして評価できるものである。
Composition of tread rubber (expressed in parts by weight) Natural rubber (R3S#4)? 0.00B R
(Nipol 1441) 41,
25 Zinc white 5.00 Stearic acid 3.00 Anti-aging agent (San
toflex 13) 2. OO Microcrystalline wax 2.00 Carbon Black N339 75.00 Sebacic acid dioctyl ester 28.75 N-oxydiethylene-2-benzodiazolylsulfenamide 1.10 Sulfur
2.00 Regarding the above six types of tires, a 1800cc FF vehicle was used as a test vehicle.
The steering stability when driving on snow (snow performance) and the steering stability when driving on dry roads (dry performance) were evaluated, and the total score was expressed on a 10-point scale, and the results are shown in the table below. Those with an evaluation score of 7 or more in the table can be evaluated as having practical tire performance.

(来夏以下余白) 表から、本発明によるタイヤCとEとは、スノー性能お
よびドライ性能とも実用性のあるタイヤ性能を発揮して
いるが、比較タイヤA、B。
(Leaving space below next summer) From the table, it can be seen that tires C and E according to the present invention exhibit practical tire performance in both snow performance and dry performance, but comparative tires A and B.

D、Fは、いずれもドライ性能かスノー性能のいずれか
一方が実用的タイヤ性能を満足していないことがわかる
It can be seen that both D and F do not satisfy the practical tire performance in either dry performance or snow performance.

〔発明の効果〕〔Effect of the invention〕

上述したように本発明の雪水路用タイヤによると、トレ
ッドゴムの一20℃での100%モジュラスを32kg
/cffl以下にするとともに、トレンド面をブロック
基調パターンに形成し、そのパターンに形成されたブロ
ックにはカーフを設けるようにしたものであるが、副溝
の深さを特定の範囲に設定したことによって、スノー性
能を何ら損なうことなく、ドライ性能の向上を図ること
ができるようになる。
As mentioned above, according to the snow channel tire of the present invention, the 100% modulus of the tread rubber at 20°C is 32 kg.
/cffl or less, the trend surface is formed into a block basic pattern, and the blocks formed in that pattern are provided with kerfs, but the depth of the minor groove is set within a specific range. This makes it possible to improve dry performance without compromising snow performance in any way.

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

第1図は本発明の実施例による雪氷路用タイヤのトレッ
ド面の一部を示す平面図、第2図は第1図のn−n矢視
図である。 1・・・主溝、 2・・・副溝、 3・・・ブロック、
4・・・カーフ。
FIG. 1 is a plan view showing a part of the tread surface of a tire for snowy and icy roads according to an embodiment of the present invention, and FIG. 2 is a view taken along the line nn in FIG. 1. 1... Main groove, 2... Minor groove, 3... Block,
4... Calf.

Claims (1)

【特許請求の範囲】[Claims] −20℃における100%モジュラスが32kg/cm
^2以下のゴムによってトレッド部を構成し、そのトレ
ッド面にタイヤ周方向に延びる複数の主溝と、タイヤ周
方向を横切る副溝とから溝面積比率が30〜50%であ
るブロック基調パターンを形成し、各ブロックにはタイ
ヤ周方向を横切り少なくとも一端が前記主溝に連通する
カーフを設け、また前記副溝の深さdを主溝深さDに対
する比率として1.0>d/D>0.4の範囲にすると
ともに、該副溝の平均深さd_a_vを主溝深さDに対
する比率として0.8>d_a_v/D>0.4の範囲
にしたことを特徴とする雪氷路用タイヤ。
100% modulus at -20℃ is 32kg/cm
The tread part is made of rubber of ^2 or less, and the tread surface has a block basic pattern with a groove area ratio of 30 to 50% from a plurality of main grooves extending in the circumferential direction of the tire and minor grooves crossing the circumferential direction of the tire. Each block is provided with a kerf that crosses the tire circumferential direction and has at least one end communicating with the main groove, and the ratio of the depth d of the sub groove to the main groove depth D is 1.0>d/D> 0.4, and the ratio of the average depth d_a_v of the minor groove to the main groove depth D is 0.8>d_a_v/D>0.4. .
JP61267673A 1986-11-12 1986-11-12 Tire for snowy and icy road Pending JPS63125410A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP61267673A JPS63125410A (en) 1986-11-12 1986-11-12 Tire for snowy and icy road

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP61267673A JPS63125410A (en) 1986-11-12 1986-11-12 Tire for snowy and icy road

Publications (1)

Publication Number Publication Date
JPS63125410A true JPS63125410A (en) 1988-05-28

Family

ID=17447933

Family Applications (1)

Application Number Title Priority Date Filing Date
JP61267673A Pending JPS63125410A (en) 1986-11-12 1986-11-12 Tire for snowy and icy road

Country Status (1)

Country Link
JP (1) JPS63125410A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5256221A (en) * 1990-09-04 1993-10-26 Uniroyal Engelbert Reifen Gmbh Pneumatic vehicle tire with mirror symmetrical tread elements
US5316062A (en) * 1990-11-15 1994-05-31 Compagnie Generale Des Etablissements Michelin - Michelin & Cie Tire tread for heavy vehicles
US5503208A (en) * 1991-05-09 1996-04-02 Bridgestone Corporation Pneumatic tires
JPH0899501A (en) * 1994-09-29 1996-04-16 Bridgestone Corp Pneumatic tire
US5580404A (en) * 1993-08-30 1996-12-03 The Goodyear Tire & Rubber Company Tread including tie bars and sipes
US7422043B2 (en) 2004-07-20 2008-09-09 Toyo Tire & Rubber Co., Ltd. Pneumatic tire with tread having circumferential sub-grooves including at least three raised portions
US20160152087A1 (en) * 2014-11-28 2016-06-02 Sumitomo Rubber Industries, Ltd. Pneumatic tire
CN107554202A (en) * 2016-06-30 2018-01-09 东洋橡胶工业株式会社 Pneumatic tire

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6042106A (en) * 1983-07-07 1985-03-06 ダンロツプ・リミテツド Tire tread
JPS60203506A (en) * 1984-03-29 1985-10-15 Bridgestone Corp Pneumatic tire
JPS61102301A (en) * 1984-10-23 1986-05-21 Bridgestone Corp Pneumatic type with superior uneven-wear resistant characteristics

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6042106A (en) * 1983-07-07 1985-03-06 ダンロツプ・リミテツド Tire tread
JPS60203506A (en) * 1984-03-29 1985-10-15 Bridgestone Corp Pneumatic tire
JPS61102301A (en) * 1984-10-23 1986-05-21 Bridgestone Corp Pneumatic type with superior uneven-wear resistant characteristics

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5256221A (en) * 1990-09-04 1993-10-26 Uniroyal Engelbert Reifen Gmbh Pneumatic vehicle tire with mirror symmetrical tread elements
US5316062A (en) * 1990-11-15 1994-05-31 Compagnie Generale Des Etablissements Michelin - Michelin & Cie Tire tread for heavy vehicles
US5503208A (en) * 1991-05-09 1996-04-02 Bridgestone Corporation Pneumatic tires
US5580404A (en) * 1993-08-30 1996-12-03 The Goodyear Tire & Rubber Company Tread including tie bars and sipes
JPH0899501A (en) * 1994-09-29 1996-04-16 Bridgestone Corp Pneumatic tire
US7422043B2 (en) 2004-07-20 2008-09-09 Toyo Tire & Rubber Co., Ltd. Pneumatic tire with tread having circumferential sub-grooves including at least three raised portions
US20160152087A1 (en) * 2014-11-28 2016-06-02 Sumitomo Rubber Industries, Ltd. Pneumatic tire
US10266012B2 (en) * 2014-11-28 2019-04-23 Sumitomo Rubber Industries, Ltd. Pneumatic tire
CN107554202A (en) * 2016-06-30 2018-01-09 东洋橡胶工业株式会社 Pneumatic tire

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